WO2017125636A1 - Device for controlling the flow of blood in a blood vessel - Google Patents

Device for controlling the flow of blood in a blood vessel Download PDF

Info

Publication number
WO2017125636A1
WO2017125636A1 PCT/ES2017/070031 ES2017070031W WO2017125636A1 WO 2017125636 A1 WO2017125636 A1 WO 2017125636A1 ES 2017070031 W ES2017070031 W ES 2017070031W WO 2017125636 A1 WO2017125636 A1 WO 2017125636A1
Authority
WO
WIPO (PCT)
Prior art keywords
chain
conduit
loop
diameter
blood vessel
Prior art date
Application number
PCT/ES2017/070031
Other languages
Spanish (es)
French (fr)
Inventor
Carlos Andrés PARDO PARDO
Antonio ORDOÑEZ FERNÁNDEZ
Israel Valverde Pérez
Sandra Liliana PARDO PRIETO
Juan MORA MACÍAS
Esther REINA ROMO
Jaime DOMÍNGUEZ ABASCAL
Original Assignee
Servicio Andaluz De Salud
Universidad De Sevilla
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Servicio Andaluz De Salud, Universidad De Sevilla filed Critical Servicio Andaluz De Salud
Publication of WO2017125636A1 publication Critical patent/WO2017125636A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/12—Surgical instruments, devices or methods, e.g. tourniquets for ligaturing or otherwise compressing tubular parts of the body, e.g. blood vessels, umbilical cord

Definitions

  • the invention pertains to the field of medicine, and more particularly to the devices used for the surgical treatment of congenital heart disease in the pulmonary artery.
  • the object of the present invention is a new device designed to control blood flow through the pulmonary artery by the banding technique.
  • the banding technique basically consists of placing a band around the main trunk of the pulmonary artery so that it is constricted, which reduces its inner section and increases the resistance to flow, which finally decreases the blood volume that reaches lungs.
  • the banding technique is performed using a medium sternotomy or thoracotomy. Once the pericardium is opened, the pulmonary artery is isolated from adjacent tissues and sufficient space is created to place the band around the main trunk (usually Teflon), which closes with a stitch. In this way, the flow through the pulmonary artery is limited, which makes it possible to balance the blood volume that reaches the lungs with the systemic blood volume.
  • the correct reduction diameter is assessed in the operating room by means of arterial oxygen saturation, blood pressure and pulmonary arterial pressure under direct measurement on the main trunk, before and after the band.
  • This procedure allows palliative and temporary control of blood flow to the pulmonary artery temporarily, avoiding endothelial remodeling, known as Eisenmenger syndrome, and poor perfusion syndrome. This allows delaying the final repair surgery until the patient has increased in weight and size.
  • a first aspect of the present invention is directed to a novel blood flow control device in a blood vessel based on the use of a chain in instead of elements such as ribbons or the like.
  • It is a chain formed by links where the maximum angle of rotation between each pair of links is limited.
  • This chain has a proximal portion provided with a loop configured to surround the blood vessel for the purpose of compressing it and a distal portion configured to close the loop by means of traction application. The user can thus control the diameter of the loop, and consequently the blood flow through the inner blood vessel to the loop, by applying traction from the distal end of the chain located near the patient's skin outside the rib cage. . Once it has been achieved that the blood vessel has the desired diameter, the distal end of the chain is fixed to prevent the endoluminal pressure of the vessel itself from causing the loop to reopen.
  • the use of a chain allows a simple reopening of the loop. Indeed, if it is desired to increase the diameter of the loop, for example when the patient has increased in size, it is necessary to move a certain chain length in the proximal direction. Normally, the tension caused by the endoluminal pressure of the blood vessel in question causes that, when the fixation of the distal end of the chain is released, a certain length of the same store tends to move proximally, thus allowing the opening of the loop. However, due to friction or the presence of hooks, sometimes the endoluminal pressure is not enough to open the loop.
  • An important advantage of the use of a chain is that, in combination with a conduit through which it runs, it is possible to "push” it proximally. Indeed, as links are introduced into the tube from its distal end, said links approach each other until they touch, and when all links inside the tube they are in contact with each other it is possible to "push” the chain by introducing more links through the distal end of the tube, which causes the exit of one or several links through its proximal end and allows the opening of the loop to be achieved.
  • Another advantage more related to the use of a chain is the ease of fixing a tensioned chain in a certain position compared to a band or belt. Indeed, getting the hook or hold of a link in the chain is very simple, since it is almost impossible for a link to slip or slide from the grip in the way that a band or tape can do.
  • this invention can be applied in general to the control of blood flow in any blood vessel of the patient, although as explained above it is especially indicated for the control of blood flow in the pulmonary artery.
  • the links that make up the chain are spheres.
  • the use of spheres is particularly useful in this context because a loop formed by a chain of spheres cannot be closed beyond a diameter corresponding to the moment at which the spheres come into contact with each other. It is thus possible to limit the angle of rotation between adjacent links of the chain in a simple manner.
  • the spheres have smooth contours and no edges, which is very suitable in the context of the invention.
  • the chain comprises a flexible outer coating, for example silicone. This outer coating facilitates the sliding of the chain and also prevents contact with body fluids from affecting its properties.
  • the chain itself it can be made of a metallic material.
  • the links in the distal portion of the chain may comprise markers visible by ultrasonography indicating the diameter of the loop. For example, it may be a numbering incorporated into the links by means of a relief.
  • the device of the invention can be configured in any way provided that a chain is used instead of elements such as bands or tapes.
  • the device further comprises a conduit having a distal end configured to be placed essentially low to the patient's skin and a proximal end configured to be located next to the blood vessel.
  • the conduit serves as a guide for the chain from a peripheral location close to the patient's skin, from which it is relatively simple to operate the distal end of the chain, to a more internal location adjacent to the vessel whose blood diameter is controlled .
  • the duct must have sufficient flexibility characteristics to accommodate the patient's tissues on the path between the position of the blood vessel inside the patient where its proximal end will be located and the peripheral position next to the patient's skin where its distal end will be located, and at the same time it must have sufficient consistency to adequately guide the chain along that path.
  • the loop can be formed in different ways. For example, it would be possible simply that the proximal end of the conduit had a fastener for the proximal end of the chain.
  • the device of the invention comprises a pin integral to the proximal end of the conduit configured to form the chain loop.
  • the pin is integral with the proximal end of the conduit only means that relative displacement of one relative to the other is prevented, so that the transmission of tensions from the distal end of the chain to the blood vessel is prevented. This is important because the application of traction to said distal end of the chain is prevented from causing a displacement of the position of the blood vessel, which could be dangerous for the patient.
  • the pin could rest on said proximal end of the conduit.
  • the pin could comprise an essentially cylindrical projection configured to snap to the proximal end of the conduit.
  • the pin can be configured in different ways, although it preferably comprises a through hole configured for the passage of the chain and a fixing element for the proximal end of the chain.
  • the device of the invention preferably further comprises a storage box connectable to the distal end of the conduit for the storage of a distal portion of the chain.
  • This storage box accumulates a distal chain portion of sufficient length to provide a sufficient range of variation in loop diameter depending on the position and diameter of the blood vessel whose flow is to be controlled.
  • the storage box further comprises a means for fixing the chain in a certain position.
  • the chain fixing means may be formed by a pair of facing projections so that they form a groove configured to engage a link in the chain.
  • the chain is tense due to the tendency of the blood vessel to recover its original diameter , and therefore it is necessary to fix its distal end.
  • the storage box can be formed by two halves that fit together allowing its tightness.
  • the storage box can be attached to the conduit in different ways as long as they are firm enough so that the connection does not separate as a result of normal stresses that occur during the life of the device.
  • the connection between the storage box and the conduit is separable. This greatly facilitates the installation procedure of the device, since it is possible to first place the conduit in an isolated manner and then fix it to the storage box.
  • the box and the duct are separable allows the duct to be obtained from elements usually found in operating rooms, such as catheters. Indeed, the duct can be obtained at from at least one section of a catheter of a suitable diameter. As for the length, it is enough to cut a section of the appropriate length depending on the length necessary for each application. This procedure will be described in more detail later in this document.
  • connection between the storage box and the conduit comprises an essentially cylindrical projection protruding from an inlet opening of the storage box and which is configured to engage the distal end of the conduit.
  • the connection between the projection and the conduit can be carried out in different ways, such as a thread.
  • the connection can be made under pressure, for example if the essentially cylindrical projection has an external taper that allows the distal end of the conduit to be coupled. Thus, it is enough to press the protrusion into the distal end of the duct.
  • the conduit is formed by the combination of an outer duct and an inner duct that projects proximally from said outer duct.
  • an outer catheter of a first diameter can be used for connection with the projection of the storage box, and then an inner catheter of a smaller second diameter can be introduced than the first diameter in the outer catheter.
  • the reason for introducing an inner catheter of smaller diameter into the outer catheter is to reduce the inner diameter of the duct so that it fits better to the diameter of the chain and thus prevent it from catching during use, for example at the end proximal duct or at the edges of the projection connecting to the storage box.
  • the duct is placed inside the patient in a position that allows a proximal position where the blood vessel whose diameter is to be controlled and a peripheral distal position close to the patient's skin is connected.
  • This operation may require adjusting the length of the duct, for example cutting it, depending on the needs of each application and particular patient.
  • the chain is then introduced through the distal orifice of the duct until it is expelled from its proximal end.
  • the pin is used to form the loop by passing the proximal end of the chain through the through hole of the pin and fixing said proximal end to a fixing element of said pin.
  • the proximal end of the chain is fixed first to the pin, then it is placed in a position adjacent to the blood vessel, and thirdly the distal end of the chain is passed through the through hole of the pin. In either case, once the loop is formed with the blood vessel located inside, it is only necessary to pull the distal end of the chain until the diameter of the loop, and therefore also the diameter of the blood vessel, is the wanted.
  • the distal end of the chain is then fixed by introducing the corresponding pair of links between the pair of facing projections of the storage box. Finally, the storage box is closed and the incision made in the patient is sutured. The blood vessel is constricted by the chain loop. If it was necessary to act on the diameter of the chain after a while, for example because the patient has increased in size, it would be enough to make a superficial incision to access the storage box. Once opened, the medical professional only has to remove the two links attached to the pair of facing projections and fix another pair of different links.
  • the medical professional can decrease the tension allowing the displacement of the chain in the proximal direction under direct vision by ultrasonography.
  • This displacement in the proximal direction can occur on its own because of the endoluminal tension of the blood vessel itself, or it may be necessary for the medical professional to "push" the chain proximally by introducing several links in the tube.
  • the medical professional must pull the chain distally.
  • a second aspect of the present invention is directed to a set of parts for the control of blood flow in a blood vessel with the aid of a conduit.
  • This set of parts mainly comprises: a) A chain formed by links where the maximum angle of rotation between each pair of links is limited, which has a proximal end provided with a loop configured to surround the blood vessel for the purpose of compressing it and a Distal end configured to close the loop by applying traction.
  • a storage box connectable to the distal end of the conduit for the storage of a distal portion of the chain, where the storage box comprises an essentially cylindrical projection protruding from an inlet opening thereof and which is configured to engage the distal end of the duct, so that the chain can travel the duct from its distal end to its proximal end and protrude through its proximal end so that it forms the loop configured to surround the blood vessel.
  • a pin attached to the proximal end of the duct configured to form the chain loop.
  • this set of parts could be marketed as is, since the user could simply obtain the conduit from one or more catheters usually present in any medical center. You would only have to choose the necessary diameter and cut a catheter section of adequate length in the operating room itself. Therefore, the procedure for using this set of parts would be identical to the previous one.
  • FIG. 1 shows a sectional view of an example of a device according to the present invention.
  • Figs. 2a and 2b respectively show the lid and the base of a storage box belonging to the example device of Fig. 1.
  • Figs. 3a and 3b respectively show an example of a pin belonging to the example of the device of Fig. 1 and a section of said pin along the plane P.
  • Figs. 4a and 4b respectively show a chain of spheres in rest position and a chain of spheres tensioned with maximum curvature.
  • Fig. 5 shows an example of a set of parts according to the present invention.
  • Fig. 6 shows a graph of the changes in the gradient, velocity and diameter along the control echocardiography performed in the rabbit 4.
  • FIG. 1 shows a sectional view of said device (1) where the main parts that comprise it are appreciated: chain (2), conduit (4), pin (5) and storage box (8). Each of them is described in more detail below.
  • Figs. 4a and 4b show a chain (2) of spheres respectively in a rest position and a closed position forming a loop of the smallest possible diameter.
  • the chain (2) of spheres is formed by a set of small diameter spheres, for example between 4 French (1.35 mm) and 6 French (2 mm), joined together to form a chain.
  • the diameter of the spheres is approximately 5 French (1, 67 mm).
  • each pair of spheres are connected to each other by means of a small rod whose ends are slidably fixed within the respective spheres. It is, for example, a chain similar to those commonly used for the plug of a bathtub. As can be seen in Fig.
  • the chain (2) of spheres is made of any biocompatible and hypoallergenic material, such as a metallic material such as titanium or steel.
  • a tube (12) of a flexible material such as silicone or the like can be used to cover the conduit and prevent it from coming directly into contact with the patient's tissues.
  • the silicone coating tube (12) has a diameter of 7 French (2.3 mm).
  • the conduit (4) can in principle be shaped in any way provided it has a diameter that allows the passage of the chain (2) of spheres inside and that has a flexibility that allows it to accommodate between the patient's tissues but at the same time properly guide the chain (2) of spheres inside without bending or wrinkling.
  • the duct (4) is formed from two sections of two conventional catheters: an outer duct (4e) and an inner duct (4i).
  • the outer duct (4e) has an approximate diameter of 14 French (4.7 mm), while the inner duct (4i) has an approximate diameter of 10 French (3.3 mm).
  • the outer diameter of the inner duct (4i) allows its tight introduction into the outer duct (4e).
  • the inner duct (4i) protrudes proximally of the outer duct (4e).
  • the pin (5) is configured to allow the formation of the loop (3) inside which the blood vessel whose flow is to be controlled will be arranged.
  • a pin (5) is used as shown in Figs. 3a and 3b.
  • This pin (5) has an essentially cylindrical shape with a transverse through hole (6) having a diameter suitable for the passage of the chain (2) of spheres and an element (7) for fixing the proximal end (2p) of the chain (2) of spheres.
  • the fixing element (7) in this specific example takes the form of a cavity located in a side wall of the cylindrical pin (5) having a shape configured to receive the sphere located at the proximal end of the chain (2) of spheres .
  • This cavity communicates with a longitudinal hole, displaced in relation to the axis of the cylindrical pin (5), which allows the insertion of two opposite screws to immobilize said sphere from the proximal end of the chain (2) of spheres.
  • the loop (3) it is only necessary to pass the proximal end of the chain (2) of spheres through the transverse through hole (6) and introduce the last proximal sphere (2) into the cavity. A pair of screws are then introduced through the respective ends of the longitudinal hole displaced in communication with the cavity to trap said last sphere.
  • the most proximal sphere of the chain (2) of spheres can be fixed first to the pin (5) with the help of the screws, and then pass the distal end of the chain (2) of spheres through the hole (6) through which the blood vessel is inside the loop (3) formed.
  • the medical professional only has to pull distally from the distal end of the chain (2), which will thus slide through the hole (6 ) through and the diameter of the loop (3) will decrease.
  • the storage box (8) serves to store the distal portion (2d) of the chain (2) of spheres.
  • This distal portion (2d) must be of sufficient length to allow different diameters of the loop (3) located in the proximal portion (2p) of said chain (2) of spheres.
  • the storage box (8) must be completely waterproof, as it will be located under the skin of the patient in contact with various body fluids for a period of time that can be quite long, of the order of several months or years.
  • the box (8) of this example is formed by a cover (8a) and a base (8b) that fit tightly together. One or more screws or the like can be used for the secure coupling of cover (8a) and base (8b).
  • the interior of the base (8b) of the storage box (8) of this example is formed by a pair of cavities (1 1a, 1 1 b).
  • the cavity (1 1a) has a small size and basically consists simply of the continuation of the entrance hole of the chain (2) of spheres in the base (8b) of the storage box (8).
  • the cavity (11 b) is larger than the previous one, since it has the function of storing the distal portion (2d) of the chain (2) of spheres.
  • the means (9) for fixing the chain (2) of spheres which in this example is formed by a pair of protrusions (9a, 9b) facing each other so that they form a groove that communicates the cavity (11 a) with the cavity (1 1 b) and that is configured to engage a sphere in the chain (2) of spheres.
  • the groove has a size such that it does not allow the passage of a complete sphere of the chain (2), but the passage of the connecting rod between adjacent spheres of the chain (2). Therefore, to fix the chain (2) of spheres in the desired position, the user only has to push down two adjacent spheres so that they are on the respective sides of the groove.
  • the cover (8a) is then placed, whose closing surface is essentially flush with the upper part of the cavities (1 1a, 1 1 b), so that the upper end of the groove is closed and no sphere is prevented can pass from the cavity (1 1 b) to the cavity (1 1a).
  • the base (1 1a) of the storage box (8) also has an outer projection (10) located in the position of the chain inlet hole (2) in the box (8) which has an essentially cylindrical shape although provided of an external conicity. In general, this conicity allows the fixing of the conduit (4) under pressure. More specifically, in the case of this example where the duct (4) is formed by an inner duct (4i) and an outer duct (4e), it is the outer duct (4e) that is coupled to the outgoing (10). Once the outer conduit (4e) has been coupled to said projection (10), the conduit (4i) can be introduced inside it until its distal end is supported against the edges of the projection (10). The inner duct (4i) must also protrude from the proximal end of the outer duct (4e).
  • FIG. 5 schematically shows a set (10) of parts for the control of blood flow in a blood vessel formed by a chain (2) of spheres, a pin (5) and a storage box (8) , which in this example is formed by a base (8a) and a cover (8b).
  • This set (10) of parts can be supplied in a bag or other container for the user to mount the device (1) during the surgical procedure itself, using one or more catheters of a suitable diameter to implement the conduit (4).
  • Table 2 shows the anatomical and hemodynamic measurements of the rabbits used in this experiment during the surgical procedure.
  • DTAP Diameter of the pulmonary artery trunk
  • PTAP Perimeter of the pulmonary artery
  • LTAP Length of the trunk of the pulmonary artery
  • PVD Right ventricle pressure
  • PTAP Lung artery trunk pressure
  • PAO Aortic Pressure
  • PB Banding perimeter around the pulmonary artery
  • NEAP Number of spheres around the pulmonary artery
  • NEC Number of spheres in the box
  • FVD Right Ventricular Failure
  • NT Pneumothorax.
  • the device was implanted without complications and the pulmonary artery was narrowed. Taking into account what happened with the previous rabbit, this time only about 0.5 millimeters in diameter (1 sphere) were closed, which corresponds to 7% of the device's loop diameter. The animal adequately exceeded the initial postoperative period, tolerated the oral route at 6 hours and evolved satisfactorily. Multiple control echocardiograms could be performed and the diameter of the device loop adjusted, all this carried out in a total period of 24 days. Two adjustments of the diameter of the device loop were made without difficulties and under simultaneous echocardiographic control. The first adjustment consisted of a decrease in the diameter of the loop through the displacement of two spheres distally, which means a reduction of approximately 1.3 millimeters. The second adjustment consisted of an increase in the loop diameter of the device to recover its initial diameter, that is, two spheres were displaced proximally.
  • Echocardiographic evaluation A baseline echocardiography was performed on the 4 rabbits, prior to the intervention, in order to know the status of their cardiac function, anatomical dimensions and the presence of shunts due to malformations. The results are shown in Table 3.
  • AFVI Fractional shortening of the left ventricle
  • DTAP Diameter of the main trunk of the pulmonary artery
  • DRPD Right pulmonary branch diameter
  • DRPI Diameter of the left pulmonary branch
  • DVP Pulmonary valve diameter
  • GAP Gradient of the pulmonary artery
  • the first modification consisted of the decrease of the diameter of the loop and the second modification consisted of the increase of the diameter of the loop until returning to its initial diameter.
  • the decrease in loop diameter of the device caused an increase in speeds and gradients
  • the increase in diameter of the loop diameter caused a decrease in speeds and gradients.
  • Fig. 6 shows a graph of the changes in the gradient, velocity and diameter along the control echocardiograms performed.
  • the use of echocardiography was a fundamental tool, with it the anatomy and baseline function of all animals was evaluated. It was found that the adjustable device of the invention adequately modified the diameter of the pulmonary artery both at the time of implantation and subsequent adjustments, and the changes in speed and gradient suffered were evaluated.
  • the diameter adjustment table according to the number of spheres (Table 1) is a very useful tool and its data was found to correlate closely with echocardiography. In the hypothetical case of not having an echocardiography device, this will allow modifications of the device safely.
  • the post-banding pressure gradients once the opening adjustment was made, immediately descended almost to the baseline values. However, it is curious that after 7 days these gradients rose slightly instead of descending. This could be justified by the right ventricular hypertrophy suffered as an adaptation to pressure overload. It was decided to continue with the previously designed protocol and it was not evaluated whether these values changed over time.
  • the pulmonary artery dilation data at the pre and postbanding levels can be related to the process of adapting the vascular wall to the pressure overload that was carried out on a healthy heart. It is unknown if this changes over time.
  • conduit (4), the pin (5) and the proximal end of the chain (2) are joined forming a single piece. This will allow the installation and uninstallation of the device (1) without opening the chest, for example through a suitable laparoscopic device.
  • the storage box (8) has an additional outlet port of the distal portion (2d) of the chain (2).
  • This additional exit hole will allow the distal portion (2d) of the chain to protrude out of the box (8) and float out of it.
  • the size of the box (8) must in any case be sufficient to accommodate the means (9) for fixing the chain (2), and at the same time be sufficient for it to exercise as a "anchor" that prevents the migration of the device (1) inside the patient's body.
  • the diameter of the chain spheres was 19 mm. However, it is found that it is possible to further decrease this diameter.
  • the decrease in the diameter of the spheres has the advantage that the displacement of a sphere in the proximal or distal direction causes smaller decreases in the diameter of the loop, with which it is possible to adjust it more precisely. Therefore, according to preferred embodiments of the invention, the diameter of the loop will be between 5 mm and 20 mm, and more preferably between 10 mm and 15 mm.

Landscapes

  • Health & Medical Sciences (AREA)
  • Surgery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Molecular Biology (AREA)
  • Vascular Medicine (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Reproductive Health (AREA)
  • Medical Informatics (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Infusion, Injection, And Reservoir Apparatuses (AREA)
  • Surgical Instruments (AREA)

Abstract

The invention relates to a device (1) for controlling the flow of blood in a blood vessel, comprising a chain (2) formed by links, having a limited maximum angle of rotation between each pair of links. According to the invention, the chain (2) includes a proximal portion (2p) equipped with a loop (3) designed to surround the blood vessel so as to compress same, and a distal portion (2d) designed to close the loop (3) with the application of traction.

Description

DISPOSITIVO DE CONTROL DE FLUJO DE SANGRE EN UN VASO SANGUÍNEO  BLOOD FLOW CONTROL DEVICE IN A BLOOD GLASS
DESCRIPCIÓN DESCRIPTION
OBJETO DE LA INVENCIÓN OBJECT OF THE INVENTION
La invención pertenece al campo de la medicina, y más particularmente a los dispositivos utilizados para el tratamiento quirúrgico de cardiopatías congénitas en la arteria pulmonar. The invention pertains to the field of medicine, and more particularly to the devices used for the surgical treatment of congenital heart disease in the pulmonary artery.
El objeto de la presente invención es un nuevo dispositivo diseñado para controlar el flujo de sangre a través de la arteria pulmonar mediante la técnica de banding. ANTECEDENTES DE LA INVENCIÓN The object of the present invention is a new device designed to control blood flow through the pulmonary artery by the banding technique. BACKGROUND OF THE INVENTION
Dentro de la clasificación de las cardiopatías congénitas existe una tipología relacionada con un flujo sanguíneo excesivo en la arteria pulmonar, secundario a una comunicación incorrecta de las cámaras cardiacas. Este flujo sanguíneo excesivo provoca, con el paso del tiempo, un remodelado de la capa endotelial de la pared arterial que conduce finalmente a una hipertensión arterial irreversible. Aunque es posible solucionar esta cardiopatía realizando una cirugía reparadora definitiva, la mayor parte de los pacientes son neonatos o lactantes cuyo peso y tamaño desaconseja la realización de un procedimiento quirúrgico de estas características. Within the classification of congenital heart disease there is a typology related to excessive blood flow in the pulmonary artery, secondary to an incorrect communication of the cardiac chambers. This excessive blood flow causes, over time, a remodeling of the endothelial layer of the arterial wall that ultimately leads to irreversible arterial hypertension. Although it is possible to solve this heart disease by performing a definitive repair surgery, most of the patients are neonates or infants whose weight and size advise against performing a surgical procedure of these characteristics.
Para solucionar este problema, en el año 1952 los doctores Muller y Danimann describieron la técnica de banding. La técnica de banding consiste fundamentalmente en colocar una banda alrededor del tronco principal de la arteria pulmonar de manera que ésta queda constreñida, con lo que se consigue disminuir su sección interior y aumentar la resistencia al flujo, que finalmente disminuye el volumen sanguíneo que llega a los pulmones. To solve this problem, in 1952 Dr. Muller and Danimann described the technique of banding. The banding technique basically consists of placing a band around the main trunk of the pulmonary artery so that it is constricted, which reduces its inner section and increases the resistance to flow, which finally decreases the blood volume that reaches lungs.
La técnica de banding se realiza mediante una esternotomía media o toracotomía. Una vez abierto el pericardio, se aisla la arteria pulmonar de los tejidos adyacentes y se crea un espacio suficiente para colocar alrededor del tronco principal la banda (generalmente de teflón), que se cierra con un punto de sutura. De este modo, se limita el flujo a través de la arteria pulmonar, lo que permite equilibrar el volumen sanguíneo que llega a los pulmones con el volumen sanguíneo sistémico. El correcto diámetro de reducción es valorado en quirófano por medio de la saturación arterial de oxígeno, la presión arterial y la presión arterial pulmonar bajo medición directa sobre el tronco principal, antes y después de la banda. The banding technique is performed using a medium sternotomy or thoracotomy. Once the pericardium is opened, the pulmonary artery is isolated from adjacent tissues and sufficient space is created to place the band around the main trunk (usually Teflon), which closes with a stitch. In this way, the flow through the pulmonary artery is limited, which makes it possible to balance the blood volume that reaches the lungs with the systemic blood volume. The correct reduction diameter is assessed in the operating room by means of arterial oxygen saturation, blood pressure and pulmonary arterial pressure under direct measurement on the main trunk, before and after the band.
Este procedimiento permite controlar temporalmente de forma paliativa y poco invasiva el flujo sanguíneo hacia la arteria pulmonar, evitando el remodelado endotelial, conocido como síndrome de Eisenmenger, y el síndrome de mala perfusión. Ello permite retrasar la cirugía reparadora definitiva hasta que el paciente ha aumentado de peso y tamaño. This procedure allows palliative and temporary control of blood flow to the pulmonary artery temporarily, avoiding endothelial remodeling, known as Eisenmenger syndrome, and poor perfusion syndrome. This allows delaying the final repair surgery until the patient has increased in weight and size.
Sin embargo, una importante limitación de esta técnica es que no es posible ejercer ningún tipo de control sobre la banda una vez se ha cerrado el tórax del paciente. Esto es importante porque los parámetros hemodinámicos del paciente cambian en el postoperatorio, lo que puede requerir un nuevo ajuste de la banda incluso. Además, el crecimiento del paciente limita el tiempo del correcto funcionamiento del dispositivo de banding. However, an important limitation of this technique is that it is not possible to exercise any type of control over the band once the patient's chest has been closed. This is important because the patient's hemodynamic parameters change in the postoperative period, which may even require a new adjustment of the band. In addition, patient growth limits the time of proper functioning of the banding device.
Para solucionar estos inconvenientes, recientemente se han desarrollado dispositivos de banding ajustables desde el exterior de la cavidad torácica. El documento de Davide del Pozzo titulado "Hydraulic remotely adjustable pulmonar/ artery banding", Proceedings of the 2010 design of medical devices conference, DMD2010, Abril 13-15, 2010, Minneapolis, EEUU, proporciona un resumen de diferentes tipos de dispositivos de banding ajustables existentes en la actualidad. To solve these problems, recently adjustable banding devices have been developed from outside the thoracic cavity. The Davide del Pozzo document entitled "Hydraulic remotely adjustable pulmonary / artery banding", Proceedings of the 2010 design of medical devices conference, DMD2010, April 13-15, 2010, Minneapolis, USA, provides a summary of different types of banding devices adjustable existing today.
Sin embargo, ninguno de estos dispositivos ha conseguido solucionar completamente la problemática descrita, y por este motivo no han llegado a instaurarse como dispositivos de uso habitual por los cirujanos cardíacos pediátricos. However, none of these devices has managed to completely solve the problem described, and for this reason they have not been established as devices commonly used by pediatric cardiac surgeons.
DESCRIPCIÓN DE LA INVENCIÓN DESCRIPTION OF THE INVENTION
Un primer aspecto de la presente invención está dirigido a un novedoso dispositivo de control de flujo de sangre en un vaso sanguíneo basado en el uso de una cadena en lugar de elementos tales como cintas o similares. Se trata de una cadena formada por eslabones donde el ángulo máximo de giro entre cada par de eslabones está limitado. Esta cadena tiene una porción proximal dotada de un lazo configurado para rodear el vaso sanguíneo con el propósito de comprimirlo y una porción distal configurada para cerrar el lazo mediante la aplicación de tracción. El usuario puede así controlar el diámetro del lazo, y en consecuencia el flujo de sangre a través del vaso sanguíneo interior al lazo, mediante la aplicación de tracción desde el extremo distal de la cadena ubicado cerca de la piel del paciente fuera de la caja torácica. Una vez se ha conseguido que el vaso sanguíneo tenga el diámetro deseado, se fija el extremo distal de la cadena para evitar que la presión endoluminal del propio vaso provoque que el lazo vuelva a abrirse. A first aspect of the present invention is directed to a novel blood flow control device in a blood vessel based on the use of a chain in instead of elements such as ribbons or the like. It is a chain formed by links where the maximum angle of rotation between each pair of links is limited. This chain has a proximal portion provided with a loop configured to surround the blood vessel for the purpose of compressing it and a distal portion configured to close the loop by means of traction application. The user can thus control the diameter of the loop, and consequently the blood flow through the inner blood vessel to the loop, by applying traction from the distal end of the chain located near the patient's skin outside the rib cage. . Once it has been achieved that the blood vessel has the desired diameter, the distal end of the chain is fixed to prevent the endoluminal pressure of the vessel itself from causing the loop to reopen.
El uso de una cadena del tipo descrito en lugar de elementos tales como cintas o similares es ventajosa por varios motivos. En primer lugar, gracias a la limitación en el ángulo de giro entre eslabones se consigue que para producir un círculo sea necesario un número mínimo de eslabones, cada uno girado respecto al eslabón contiguo el máximo ángulo permitido. Esto implica que la cadena tenga una curvatura máxima que no es posible superar, lo que evita pinzamientos e irregularidades indeseadas en la compresión del vaso sanguíneo. The use of a chain of the type described instead of elements such as tapes or the like is advantageous for several reasons. In the first place, thanks to the limitation in the angle of rotation between links, it is achieved that in order to produce a circle a minimum number of links is necessary, each rotated with respect to the adjacent link the maximum allowed angle. This implies that the chain has a maximum curvature that cannot be overcome, which avoids unwanted impingement and irregularities in the compression of the blood vessel.
Además, el uso de una cadena permite realizar de una manera sencilla la reapertura del lazo. En efecto, si se desea aumentar el diámetro del lazo, por ejemplo cuando el paciente ha aumentado de tamaño, es necesario desplazar una determinada longitud de cadena en sentido proximal. Normalmente, la tensión provocada por la propia presión endoluminal del vaso sanguíneo en cuestión hace que, cuando se suelta la fijación del extremo distal de la cadena, una determinada longitud de la misma tienda a desplazarse en sentido proximal, permitiendo así la apertura del lazo. Sin embargo, debido al rozamiento o a la presencia de enganches, en ocasiones la presión endoluminal no es suficiente para abrir el lazo. Para resolver este problema, si se utilizase una banda o cinta sería necesario reabrir al paciente para liberar la presión del vaso sanguíneo, lo que conllevaría múltiples inconvenientes y riesgos. Una importante ventaja del uso de una cadena es que, en combinación con un conducto por cuyo interior discurre, es posible "empujarla" en sentido proximal. En efecto, a medida que se introducen eslabones dentro del tubo desde su extremo distal, dichos eslabones se acercan unos a otros hasta que se tocan, y cuando todos los eslabones del interior del tubo están en contacto entre sí es posible "empujar" la cadena introduciendo más eslabones por el extremo distal del tubo, lo que provoca la salida de uno o varios eslabones a través de su extremo proximal y permite conseguir la apertura del lazo. In addition, the use of a chain allows a simple reopening of the loop. Indeed, if it is desired to increase the diameter of the loop, for example when the patient has increased in size, it is necessary to move a certain chain length in the proximal direction. Normally, the tension caused by the endoluminal pressure of the blood vessel in question causes that, when the fixation of the distal end of the chain is released, a certain length of the same store tends to move proximally, thus allowing the opening of the loop. However, due to friction or the presence of hooks, sometimes the endoluminal pressure is not enough to open the loop. To solve this problem, if a band or tape were used, it would be necessary to reopen the patient to relieve blood vessel pressure, which would entail multiple inconveniences and risks. An important advantage of the use of a chain is that, in combination with a conduit through which it runs, it is possible to "push" it proximally. Indeed, as links are introduced into the tube from its distal end, said links approach each other until they touch, and when all links inside the tube they are in contact with each other it is possible to "push" the chain by introducing more links through the distal end of the tube, which causes the exit of one or several links through its proximal end and allows the opening of the loop to be achieved.
Otra ventaja más relacionada con el uso de una cadena es la facilidad para fijar en una posición determinada una cadena sometida a tracción en comparación con una banda o cinta. En efecto, conseguir el enganche o sujeción de un eslabón de la cadena resulta muy sencillo, ya que es casi imposible que un eslabón se escurra o deslice del agarre del modo en que lo puede hacer una banda o cinta. Another advantage more related to the use of a chain is the ease of fixing a tensioned chain in a certain position compared to a band or belt. Indeed, getting the hook or hold of a link in the chain is very simple, since it is almost impossible for a link to slip or slide from the grip in the way that a band or tape can do.
En definitiva, esta invención puede aplicarse en general al control del flujo de sangre en cualquier vaso sanguíneo del paciente, aunque como se ha explicado con anterioridad está especialmente indicada para el control del flujo de sangre en la arteria pulmonar. In short, this invention can be applied in general to the control of blood flow in any blood vessel of the patient, although as explained above it is especially indicated for the control of blood flow in the pulmonary artery.
En una realización particularmente preferida de la invención, los eslabones que conforman la cadena son esferas. El uso de esferas es particularmente útil en este contexto porque un lazo formado por una cadena de esferas no puede cerrarse más allá de un diámetro correspondiente al momento en que las esferas entran en contacto unas con otras. Se consigue así limitar de una manera sencilla el ángulo de giro entre eslabones contiguos de la cadena. Además, las esferas tienen unos contornos suaves y carentes de aristas, lo que es muy adecuado en el contexto de la invención. Preferentemente, la cadena comprende un recubrimiento exterior flexible, por ejemplo de silicona. Este recubrimiento exterior facilita el deslizamiento de la cadena y evita además que el contacto con los fluidos corporales pueda afectar a sus propiedades. En cuanto a la cadena propiamente dicha, puede estar hecha de un material metálico. Por ejemplo, se pueden utilizar materiales metálicos biocomatibles e hipoalergénicos tales como el acero o el titanio. Además, los eslabones de la porción distal de la cadena pueden comprender unos marcadores visibles por ultrasonografía que indican el diámetro del lazo. Por ejemplo, puede tratarse de una numeración incorporada en los eslabones mediante un relieve. En principio, el dispositivo de la invención puede configurarse de cualquier modo siempre que se utilice una cadena en lugar de elementos tales como bandas o cintas. Sin embargo, en una realización preferida de la invención el dispositivo además comprende un conducto que tiene un extremo distal configurado para situarse esencialmente bajo a la piel del paciente y un extremo proximal configurado para ubicarse junto al vaso sanguíneo. Ello permite que la cadena recorra el conducto desde su extremo distal hasta su extremo proximal, sobresaliendo por el extremo proximal de dicho conducto para formar el lazo configurado para rodear el vaso sanguíneo. Como se ha comentado, este lazo puede cerrarse mediante la aplicación de tracción a la cadena desde el extremo distal del conducto. En esta configuración, el conducto sirve de guía para la cadena desde una localización periférica cercana a la piel del paciente, desde la que es relativamente sencillo accionar el extremo distal de la cadena, hasta una localización más interior adyacente al vaso cuyo sanguíneo diámetro se controla. Nótese que el conducto debe presentar unas características de flexibilidad suficientes como para acomodarse a los tejidos del paciente en el camino entre la posición del vaso sanguíneo en el interior del paciente donde se ubicará su extremo proximal y la posición periférica junto a la piel del paciente donde se ubicará su extremo distal, y al mismo tiempo debe tener una consistencia suficiente como para guiar adecuadamente la cadena a lo largo de dicho camino. El lazo se puede formar de diferentes modos. Por ejemplo, sería posible simplemente que el extremo proximal del conducto tuviese un elemento de fijación para el extremo proximal de la cadena. Sin embargo, preferentemente el dispositivo de la invención comprende un pasador solidario al extremo proximal del conducto configurado para formar el lazo de la cadena. El hecho de que el pasador sea solidario al extremo proximal del conducto únicamente significa que se impide el desplazamiento relativo de uno con relación al otro, de modo que se evita la transmisión de las tensiones desde el extremo distal de la cadena hasta el vaso sanguíneo. Esto es importante porque se impide que la aplicación de tracción a dicho extremo distal de la cadena provoque un desplazamiento de la posición del vaso sanguíneo, lo que podría resultar peligroso para el paciente. Por ejemplo, el pasador podría apoyarse en dicho extremo proximal del conducto. En otro ejemplo, el pasador podría comprender un saliente esencialmente cilindrico configurado para acoplarse a presión al extremo proximal del conducto. El pasador puede configurarse de diferentes modos, aunque preferentemente comprende un orificio pasante configurado para el paso de la cadena y un elemento de fijación para el extremo proximal de la cadena. Así, el usuario sólo tiene que fijar el extremo proximal de la cadena al elemento de fijación del pasador, a continuación hacer pasar el extremo distal de la cadena a través del orificio pasante, y finalmente tirar del mismo hasta que el lazo tenga el diámetro deseado. El dispositivo de la invención preferentemente comprende además una caja de almacenamiento conectable al extremo distal del conducto para el almacenamiento de una porción distal de la cadena. Esta caja de almacenamiento acumula una porción distal de cadena de una longitud suficiente como para proporcionar un margen suficiente de variación de diámetro del lazo en función de la posición y diámetro del vaso sanguíneo cuyo flujo se va a controlar. Más preferentemente, la caja de almacenamiento además comprende un medio de fijación de la cadena en una posición determinada. Por ejemplo, el medio de fijación de la cadena puede estar formado por un par de salientes enfrentados de modo que forman una ranura configurada para enganchar un eslabón de la cadena. En efecto, una vez el profesional médico ha aplicado tracción desde el extremo distal de la cadena para disminuir el diámetro del lazo, y por tanto la sección del vaso sanguíneo, la cadena queda tensa debido a la tendencia del vaso sanguíneo a recuperar su diámetro original, y por ello es necesario fijar su extremo distal. En este ejemplo, basta con hacer pasar un par de eslabones de la porción distal alojada en la caja de almacenamiento respectivamente a cada lado del par de salientes enfrentados para que la cadena quede inmovilizada en sentido longitudinal. Además, como se describirá con mayor detalle más adelante en este documento, la caja de almacenamiento puede estar formada por dos mitades que encajan entre sí permitiendo su unión de manera hermética. In a particularly preferred embodiment of the invention, the links that make up the chain are spheres. The use of spheres is particularly useful in this context because a loop formed by a chain of spheres cannot be closed beyond a diameter corresponding to the moment at which the spheres come into contact with each other. It is thus possible to limit the angle of rotation between adjacent links of the chain in a simple manner. In addition, the spheres have smooth contours and no edges, which is very suitable in the context of the invention. Preferably, the chain comprises a flexible outer coating, for example silicone. This outer coating facilitates the sliding of the chain and also prevents contact with body fluids from affecting its properties. As for the chain itself, it can be made of a metallic material. For example, biocomatible and hypoallergenic metal materials such as steel or titanium can be used. In addition, the links in the distal portion of the chain may comprise markers visible by ultrasonography indicating the diameter of the loop. For example, it may be a numbering incorporated into the links by means of a relief. In principle, the device of the invention can be configured in any way provided that a chain is used instead of elements such as bands or tapes. However, in a preferred embodiment of the invention, the device further comprises a conduit having a distal end configured to be placed essentially low to the patient's skin and a proximal end configured to be located next to the blood vessel. This allows the chain to travel from the distal end to its proximal end, protruding from the proximal end of said conduit to form the loop configured to surround the blood vessel. As mentioned, this loop can be closed by applying traction to the chain from the distal end of the duct. In this configuration, the conduit serves as a guide for the chain from a peripheral location close to the patient's skin, from which it is relatively simple to operate the distal end of the chain, to a more internal location adjacent to the vessel whose blood diameter is controlled . Note that the duct must have sufficient flexibility characteristics to accommodate the patient's tissues on the path between the position of the blood vessel inside the patient where its proximal end will be located and the peripheral position next to the patient's skin where its distal end will be located, and at the same time it must have sufficient consistency to adequately guide the chain along that path. The loop can be formed in different ways. For example, it would be possible simply that the proximal end of the conduit had a fastener for the proximal end of the chain. However, preferably the device of the invention comprises a pin integral to the proximal end of the conduit configured to form the chain loop. The fact that the pin is integral with the proximal end of the conduit only means that relative displacement of one relative to the other is prevented, so that the transmission of tensions from the distal end of the chain to the blood vessel is prevented. This is important because the application of traction to said distal end of the chain is prevented from causing a displacement of the position of the blood vessel, which could be dangerous for the patient. For example, the pin could rest on said proximal end of the conduit. In another example, the pin could comprise an essentially cylindrical projection configured to snap to the proximal end of the conduit. The pin can be configured in different ways, although it preferably comprises a through hole configured for the passage of the chain and a fixing element for the proximal end of the chain. Thus, the user only You have to fix the proximal end of the chain to the pin fixing element, then pass the distal end of the chain through the through hole, and finally pull it until the loop has the desired diameter. The device of the invention preferably further comprises a storage box connectable to the distal end of the conduit for the storage of a distal portion of the chain. This storage box accumulates a distal chain portion of sufficient length to provide a sufficient range of variation in loop diameter depending on the position and diameter of the blood vessel whose flow is to be controlled. More preferably, the storage box further comprises a means for fixing the chain in a certain position. For example, the chain fixing means may be formed by a pair of facing projections so that they form a groove configured to engage a link in the chain. Indeed, once the medical professional has applied traction from the distal end of the chain to decrease the diameter of the loop, and therefore the section of the blood vessel, the chain is tense due to the tendency of the blood vessel to recover its original diameter , and therefore it is necessary to fix its distal end. In this example, it is sufficient to pass a pair of links of the distal portion housed in the storage box respectively on each side of the pair of facing projections so that the chain is immobilized longitudinally. In addition, as will be described in greater detail later in this document, the storage box can be formed by two halves that fit together allowing its tightness.
En principio, la caja de almacenamiento puede estar unida al conducto de diferentes modos siempre que sean lo suficientemente firmes como para que la conexión no se separe a consecuencia de las tensiones normales que se producen durante la vida útil del dispositivo. En una realización especialmente preferida de la invención, la conexión entre la caja de almacenamiento y el conducto es separable. Esto facilita enormemente el procedimiento de instalación del dispositivo, ya que es posible colocar en primer lugar el conducto de manera aislada para posteriormente fijarlo a la caja de almacenamiento. Además, el hecho de que la caja y el conducto sean separables permite obtener el conducto a partir de elementos que se encuentran habitualmente en los quirófanos, como por ejemplo catéteres. En efecto, el conducto puede obtenerse a partir de al menos un tramo de un catéter de un diámetro adecuado. En cuanto a la longitud, basta con cortar un tramo de la longitud adecuada en función de la longitud necesaria para cada aplicación. Este procedimiento se describirá con mayor detalle más adelante en este documento. In principle, the storage box can be attached to the conduit in different ways as long as they are firm enough so that the connection does not separate as a result of normal stresses that occur during the life of the device. In a particularly preferred embodiment of the invention, the connection between the storage box and the conduit is separable. This greatly facilitates the installation procedure of the device, since it is possible to first place the conduit in an isolated manner and then fix it to the storage box. In addition, the fact that the box and the duct are separable allows the duct to be obtained from elements usually found in operating rooms, such as catheters. Indeed, the duct can be obtained at from at least one section of a catheter of a suitable diameter. As for the length, it is enough to cut a section of the appropriate length depending on the length necessary for each application. This procedure will be described in more detail later in this document.
Más preferentemente, la conexión entre la caja de almacenamiento y el conducto comprende un saliente esencialmente cilindrico que sobresale de un orificio de entrada de la caja de almacenamiento y que está configurado para acoplarse al extremo distal del conducto. La conexión entre el saliente y el conducto puede llevarse a cabo de diferentes modos, como por ejemplo a rosca. Alternativamente, la conexión puede realizarse a presión, por ejemplo si el saliente esencialmente cilindrico tiene una conicidad externa que permita el acoplamiento del extremo distal del conducto. De ese modo, basta con introducir a presión el saliente en el extremo distal del conducto. En una realización especialmente preferida de la invención, el conducto está formado por la combinación de un conducto exterior y un conducto interior que sobresale proximalmente de dicho conducto exterior. Esta configuración es especialmente adecuada cuando se utilizan elementos tales como catéteres para conformar el conducto: se puede utilizar un catéter exterior de un primer diámetro para la conexión con el saliente de la caja de almacenamiento, y a continuación introducir un catéter interior de un segundo diámetro menor que el primer diámetro en el catéter exterior. El motivo por el cual se introduce un catéter interior de menor diámetro dentro del catéter exterior es reducir el diámetro interior del conducto para que se ajuste mejor al diámetro de la cadena y evitar así que ésta se enganche durante el uso, por ejemplo en el extremo proximal del conducto o en los bordes del saliente de conexión con la caja de almacenamiento. More preferably, the connection between the storage box and the conduit comprises an essentially cylindrical projection protruding from an inlet opening of the storage box and which is configured to engage the distal end of the conduit. The connection between the projection and the conduit can be carried out in different ways, such as a thread. Alternatively, the connection can be made under pressure, for example if the essentially cylindrical projection has an external taper that allows the distal end of the conduit to be coupled. Thus, it is enough to press the protrusion into the distal end of the duct. In a particularly preferred embodiment of the invention, the conduit is formed by the combination of an outer duct and an inner duct that projects proximally from said outer duct. This configuration is especially suitable when elements such as catheters are used to form the conduit: an outer catheter of a first diameter can be used for connection with the projection of the storage box, and then an inner catheter of a smaller second diameter can be introduced than the first diameter in the outer catheter. The reason for introducing an inner catheter of smaller diameter into the outer catheter is to reduce the inner diameter of the duct so that it fits better to the diameter of the chain and thus prevent it from catching during use, for example at the end proximal duct or at the edges of the projection connecting to the storage box.
El uso del dispositivo descrito sería fundamentalmente el siguiente. En primer lugar, se coloca el conducto en el interior del paciente en una posición que permita conectar una posición proximal donde se encuentra el vaso sanguíneo cuyo diámetro se va a controlar y una posición distal periférica cercana a la piel del paciente. Esta operación puede requerir ajusfar la longitud del conducto, por ejemplo cortándolo, en función de las necesidades de cada aplicación y paciente particular. Como se ha descrito anteriormente, es necesario que el conducto tenga una cierta flexibilidad para poder acomodarse a los tejidos del paciente en la posición deseada. Una vez el conducto está situado en posición, se fija su extremo distal a la caja de almacenamiento acoplando dicho extremo distal al saliente dotado de una conicidad externa de la caja de almacenamiento. Si es necesario, se introduce un conducto interior dentro del conducto mencionado anteriormente, que en ese caso sería el conducto exterior. A continuación se introduce la cadena por el orificio distal del conducto hasta hacerla salir por su extremo proximal. Se utiliza el pasador para formar el lazo haciendo pasar el extremo proximal de la cadena por el orificio pasante del pasador y fijando dicho extremo proximal a un elemento de fijación de dicho pasador. Alternativamente, se fija primero el extremo proximal de la cadena al pasador, luego se coloca éste en una posición adyacente al vaso sanguíneo, y en tercer lugar se hace pasar el extremo distal de la cadena por el orificio pasante del pasador. En cualquiera de los casos, una vez el lazo está formado con el vaso sanguíneo ubicado en su interior, sólo es necesario tirar del extremo distal de la cadena hasta que el diámetro del lazo, y por tanto también el diámetro del vaso sanguíneo, sea el deseado. Se fija entonces el extremo distal de la cadena introduciendo el par de eslabones que corresponda entre el par de salientes enfrentados de la caja de almacenamiento. Por último, se cierra la caja de almacenamiento y se sutura la incisión realizada en el paciente. El vaso sanguíneo queda constreñido por el lazo de la cadena. En caso de que fuese necesario actuar sobre el diámetro de la cadena pasado un tiempo, por ejemplo debido a que el paciente ha aumentado de tamaño, bastaría con realizar una incisión superficial para acceder a la caja de almacenamiento. Una vez abierta, el profesional médico sólo tiene que extraer los dos eslabones fijados al par de salientes enfrentados y fijar otro par de eslabones diferentes. En este caso, si se supone que el diámetro del vaso sanguíneo ha aumentado como consecuencia del crecimiento del paciente, el profesional médico puede disminuir la tensión permitiendo el desplazamiento de la cadena en sentido proximal bajo visión directa por ultrasonografía. Este desplazamiento en sentido proximal puede producirse por sí solo a causa de la tensión endoluminal del propio vaso sanguíneo, o bien puede ser necesario que el profesional médico "empuje" la cadena en sentido proximal mediante la introducción de varios eslabones en el tubo. Por el contrario, si es necesario limitar aún más el flujo de sangre por el vaso sanguíneo, el profesional médico debe tirar de la cadena en sentido distal. The use of the described device would be essentially the following. First, the duct is placed inside the patient in a position that allows a proximal position where the blood vessel whose diameter is to be controlled and a peripheral distal position close to the patient's skin is connected. This operation may require adjusting the length of the duct, for example cutting it, depending on the needs of each application and particular patient. As described above, it is necessary for the duct to have a certain flexibility in order to accommodate the patient's tissues in the desired position. Once the duct is placed in position, its distal end is fixed to the storage box by coupling said distal end to the projection provided with an external taper of the storage box. If necessary, an inner conduit is introduced into the conduit mentioned above, which in that case would be the outer conduit. The chain is then introduced through the distal orifice of the duct until it is expelled from its proximal end. The pin is used to form the loop by passing the proximal end of the chain through the through hole of the pin and fixing said proximal end to a fixing element of said pin. Alternatively, the proximal end of the chain is fixed first to the pin, then it is placed in a position adjacent to the blood vessel, and thirdly the distal end of the chain is passed through the through hole of the pin. In either case, once the loop is formed with the blood vessel located inside, it is only necessary to pull the distal end of the chain until the diameter of the loop, and therefore also the diameter of the blood vessel, is the wanted. The distal end of the chain is then fixed by introducing the corresponding pair of links between the pair of facing projections of the storage box. Finally, the storage box is closed and the incision made in the patient is sutured. The blood vessel is constricted by the chain loop. If it was necessary to act on the diameter of the chain after a while, for example because the patient has increased in size, it would be enough to make a superficial incision to access the storage box. Once opened, the medical professional only has to remove the two links attached to the pair of facing projections and fix another pair of different links. In this case, if it is assumed that the diameter of the blood vessel has increased as a result of the growth of the patient, the medical professional can decrease the tension allowing the displacement of the chain in the proximal direction under direct vision by ultrasonography. This displacement in the proximal direction can occur on its own because of the endoluminal tension of the blood vessel itself, or it may be necessary for the medical professional to "push" the chain proximally by introducing several links in the tube. On the contrary, if it is necessary to further limit the flow of blood through the blood vessel, the medical professional must pull the chain distally.
Un segundo aspecto de la presente invención está dirigido a un conjunto de partes para el control de flujo de sangre en un vaso sanguíneo con ayuda de un conducto. Este conjunto de partes fundamentalmente comprende: a) Una cadena formada por eslabones donde el ángulo máximo de giro entre cada par de eslabones está limitado, que tiene un extremo proximal dotado de un lazo configurado para rodear el vaso sanguíneo con el propósito de comprimirlo y un extremo distal configurado para cerrar el lazo mediante la aplicación de tracción. b) Una caja de almacenamiento conectable al extremo distal del conducto para el almacenamiento de una porción distal de la cadena, donde la caja de almacenamiento comprende un saliente esencialmente cilindrico que sobresale de un orificio de entrada de la misma y que está configurado para acoplarse al extremo distal del conducto, de modo que la cadena puede recorrer el conducto desde su extremo distal hasta su extremo proximal y sobresalir por su extremo proximal de modo que forma el lazo configurado para rodear el vaso sanguíneo. c) Un pasador solidario al extremo proximal del conducto configurado para formar el lazo de la cadena. A second aspect of the present invention is directed to a set of parts for the control of blood flow in a blood vessel with the aid of a conduit. This set of parts mainly comprises: a) A chain formed by links where the maximum angle of rotation between each pair of links is limited, which has a proximal end provided with a loop configured to surround the blood vessel for the purpose of compressing it and a Distal end configured to close the loop by applying traction. b) A storage box connectable to the distal end of the conduit for the storage of a distal portion of the chain, where the storage box comprises an essentially cylindrical projection protruding from an inlet opening thereof and which is configured to engage the distal end of the duct, so that the chain can travel the duct from its distal end to its proximal end and protrude through its proximal end so that it forms the loop configured to surround the blood vessel. c) A pin attached to the proximal end of the duct configured to form the chain loop.
En efecto, este conjunto de partes se podría comercializar tal cual, ya que el usuario podría obtener el conducto simplemente a partir de uno o varios catéteres habitualmente presentes en cualquier centro médico. Sólo tendría que elegir el diámetro necesario y cortar en el propio quirófano durante la operación un tramo de catéter de longitud adecuada. Por lo tanto, el procedimiento de uso de este conjunto de partes sería idéntico al anterior. Indeed, this set of parts could be marketed as is, since the user could simply obtain the conduit from one or more catheters usually present in any medical center. You would only have to choose the necessary diameter and cut a catheter section of adequate length in the operating room itself. Therefore, the procedure for using this set of parts would be identical to the previous one.
BREVE DESCRIPCIÓN DE LAS FIGURAS La Fig. 1 muestra una vista en sección de un ejemplo de dispositivo de acuerdo con la presente invención. BRIEF DESCRIPTION OF THE FIGURES Fig. 1 shows a sectional view of an example of a device according to the present invention.
Las Figs. 2a y 2b muestran respectivamente la tapa y la base de una caja de almacenamiento perteneciente al ejemplo de dispositivo de la Fig. 1. Las Figs. 3a y 3b muestran respectivamente un ejemplo de pasador perteneciente al ejemplo de dispositivo de la Fig. 1 y una sección de dicho pasador por el plano P. Figs. 2a and 2b respectively show the lid and the base of a storage box belonging to the example device of Fig. 1. Figs. 3a and 3b respectively show an example of a pin belonging to the example of the device of Fig. 1 and a section of said pin along the plane P.
Las Figs. 4a y 4b muestran respectivamente una cadena de esferas en posición de reposo y una cadena de esferas tensionada con la máxima curvatura. Figs. 4a and 4b respectively show a chain of spheres in rest position and a chain of spheres tensioned with maximum curvature.
La Fig. 5 muestra un ejemplo de conjunto de partes de acuerdo con la presente invención. La Fig. 6 muestra una gráfica de los cambios en el gradiente, velocidad y diámetro a lo largo de las ecocardiografías de control realizadas en el conejo 4. Fig. 5 shows an example of a set of parts according to the present invention. Fig. 6 shows a graph of the changes in the gradient, velocity and diameter along the control echocardiography performed in the rabbit 4.
REALIZACIONES PREFERENTES DE LA INVENCIÓN Se describe a continuación un ejemplo de dispositivo (1) de control de flujo de sangre en un vaso sanguíneo de acuerdo con la presente invención donde se utiliza una cadena (2) cuyos eslabones son esferas. La Fig. 1 muestra una vista en sección de dicho dispositivo (1) donde se aprecian las principales partes que lo componen: cadena (2), conducto (4), pasador (5) y caja (8) de almacenamiento. A continuación, se describe cada uno de ellos con mayor detalle. PREFERRED EMBODIMENTS OF THE INVENTION An example of a blood flow control device (1) in a blood vessel according to the present invention where a chain (2) whose links are spheres is used is described below. Fig. 1 shows a sectional view of said device (1) where the main parts that comprise it are appreciated: chain (2), conduit (4), pin (5) and storage box (8). Each of them is described in more detail below.
Cadena (2) Chain (2)
Las Figs. 4a y 4b muestran una cadena (2) de esferas respectivamente en una posición de reposo y una posición cerrada formando un lazo del menor diámetro posible. La cadena (2) de esferas está formada por un conjunto de esferas de pequeño diámetro, por ejemplo de entre 4 French (1 ,35 mm) y 6 French (2 mm), unidas entre sí para formar una cadena. En este ejemplo concreto, el diámetro de las esferas es de aproximadamente 5 French (1 ,67 mm). Como es conocido, cada par de esferas están conectada entre sí por medio de un pequeño vástago cuyos extremos están fijados de manera deslizante dentro de las respectivas esferas. Se trata, por ejemplo, una cadena similar a las utilizadas habitualmente para el tapón de una bañera. Como se puede apreciar en la Fig. 4a, por debajo de una curvatura máxima la cadena (2) de esferas se comporta de una manera similar a una cinta o banda. Sin embargo, cuando se intenta formar un lazo del menor diámetro posible, es decir, cuando se intenta aumentar la curvatura de la cadena (2), como se muestra en la Fig. 4b, existe un momento en que cada esfera choca con las esferas adyacentes e impide que el diámetro de la cadena (2) de esferas pueda disminuir más. Este diámetro corresponde a una curvatura máxima que no se puede superar, ya que, como se ha comentado con anterioridad en este documento, el ángulo de giro entre eslabones adyacentes de la cadena está limitado. Esta característica es especialmente ventajosa en el contexto de la invención, ya que impide que puedan formarse pinzamientos en el vaso sanguíneo cuyo diámetro se va a controlar. Figs. 4a and 4b show a chain (2) of spheres respectively in a rest position and a closed position forming a loop of the smallest possible diameter. The chain (2) of spheres is formed by a set of small diameter spheres, for example between 4 French (1.35 mm) and 6 French (2 mm), joined together to form a chain. In this specific example, the diameter of the spheres is approximately 5 French (1, 67 mm). As is known, each pair of spheres are connected to each other by means of a small rod whose ends are slidably fixed within the respective spheres. It is, for example, a chain similar to those commonly used for the plug of a bathtub. As can be seen in Fig. 4a, below a maximum curvature the chain (2) of spheres behaves in a manner similar to a tape or band. However, when trying to form a loop of the smallest possible diameter, that is, when trying to increase the curvature of the chain (2), as shown in Fig. 4b, there is a time when each sphere collides with the spheres adjacent and prevents the diameter of the chain (2) of spheres from being able to decrease further. This diameter corresponds to a maximum curvature that cannot be exceeded, since, as mentioned earlier in this document, the angle of rotation between adjacent links of the chain is limited. This characteristic is especially advantageous in the context of the invention, since it prevents the formation of impingements in the blood vessel whose diameter is to be controlled.
La cadena (2) de esferas está hecha de cualquier material biocompatible e hipoalergénico, como por ejemplo un material metálico tal como el titanio o el acero. Además, puede utilizarse un tubo (12) de un material flexible tal como silicona o similar para recubrir el conducto y evitar que entre directamente en contacto con los tejidos del paciente. En este ejemplo, el tubo (12) de recubrimiento de silicona presenta un diámetro de 7 French (2,3 mm). The chain (2) of spheres is made of any biocompatible and hypoallergenic material, such as a metallic material such as titanium or steel. In addition, a tube (12) of a flexible material such as silicone or the like can be used to cover the conduit and prevent it from coming directly into contact with the patient's tissues. In this example, the silicone coating tube (12) has a diameter of 7 French (2.3 mm).
Conducto (4) Duct (4)
Como se ha mencionado con anterioridad, el conducto (4) puede en principio estar conformado de cualquier modo siempre que tenga un diámetro que permita el paso de la cadena (2) de esferas por su interior y que tenga una flexibilidad tal que permita acomodarlo entre los tejidos del paciente pero que al mismo tiempo guie adecuadamente la cadena (2) de esferas por su interior sin doblarse ni arrugarse. En el ejemplo que se muestra en la Fig. 1 , el conducto (4) está conformado a partir de dos tramos de sendos catéteres convencionales: un conducto exterior (4e) y un conducto interior (4i). En este ejemplo, el conducto exterior (4e) tiene un diámetro aproximado de 14 French (4,7 mm), mientras que el conducto interior (4i) tiene un diámetro aproximado de 10 French (3,3 mm). El diámetro exterior del conducto interior (4i) permite su introducción ajustada dentro del conducto exterior (4e). Además, el conducto interior (4i) sobresale proximalmente del conducto exterior (4e). As mentioned previously, the conduit (4) can in principle be shaped in any way provided it has a diameter that allows the passage of the chain (2) of spheres inside and that has a flexibility that allows it to accommodate between the patient's tissues but at the same time properly guide the chain (2) of spheres inside without bending or wrinkling. In the example shown in Fig. 1, the duct (4) is formed from two sections of two conventional catheters: an outer duct (4e) and an inner duct (4i). In this example, the outer duct (4e) has an approximate diameter of 14 French (4.7 mm), while the inner duct (4i) has an approximate diameter of 10 French (3.3 mm). The outer diameter of the inner duct (4i) allows its tight introduction into the outer duct (4e). In addition, the inner duct (4i) protrudes proximally of the outer duct (4e).
El uso de catéteres convencionales para implementar el conducto (4), ya sea a través de un único catéter o de varios que se introducen unos dentro de otros, constituye una gran ventaja de la invención. En efecto, ello permite al personal médico elegir el conducto (4) de diámetro más adecuado a cada caso en función del diámetro de las esferas de la cadena (2), así como cortar la longitud que mejor se ajuste al tamaño del paciente y a la posición del vaso sanguíneo y la caja (8) de almacenamiento. Si se produce cualquier error, basta con tomar otro trozo de catéter y volver a realizar la operación, ya que se trata de elementos habitualmente presentes en cualquier centro médico. The use of conventional catheters to implement the conduit (4), either through a single catheter or several that are introduced into each other, constitutes a great advantage of the invention. In fact, this allows medical personnel to choose the conduit (4) of the most appropriate diameter for each case based on the diameter of the spheres of the chain (2), as well as cut the length that best fits the patient's size and position of the blood vessel and storage box (8). If any error occurs, simply take another piece of catheter and perform the operation again, since these are elements usually present in any medical center.
Pasador (5) Pin (5)
El pasador (5) está configurado para permitir la formación del lazo (3) en cuyo interior se dispondrá el vaso sanguíneo cuyo flujo se va a controlar. Para ello, en este ejemplo se utiliza un pasador (5) como el mostrado en las Figs. 3a y 3b. Este pasador (5) tiene una forma esencialmente cilindrica con un orificio (6) pasante transversal que tiene un diámetro adecuado para el paso de la cadena (2) de esferas y un elemento (7) de fijación del extremo proximal (2p) de la cadena (2) de esferas. El elemento (7) de fijación adopta en este ejemplo concreto la forma de una cavidad ubicada en una pared lateral del pasador (5) cilindrico que tiene una forma configurada para recibir la esfera situada en el extremo proximal de la cadena (2) de esferas. Esta cavidad se comunica con un orificio longitudinal, desplazado con relación al eje del pasador (5) cilindrico, que permite la inserción de sendos tornillos opuestos para inmovilizar dicha esfera del extremo proximal de la cadena (2) de esferas. The pin (5) is configured to allow the formation of the loop (3) inside which the blood vessel whose flow is to be controlled will be arranged. For this, in this example a pin (5) is used as shown in Figs. 3a and 3b. This pin (5) has an essentially cylindrical shape with a transverse through hole (6) having a diameter suitable for the passage of the chain (2) of spheres and an element (7) for fixing the proximal end (2p) of the chain (2) of spheres. The fixing element (7) in this specific example takes the form of a cavity located in a side wall of the cylindrical pin (5) having a shape configured to receive the sphere located at the proximal end of the chain (2) of spheres . This cavity communicates with a longitudinal hole, displaced in relation to the axis of the cylindrical pin (5), which allows the insertion of two opposite screws to immobilize said sphere from the proximal end of the chain (2) of spheres.
Con esta configuración del pasador (5), se produce un contacto directo entre la pared lateral cilindrica del pasador (5) y el propio vaso sanguíneo cuyo diámetro se controla. Este contacto provoca una deformación de la pared del vaso sanguíneo que ayuda modificar el flujo laminar endoluminar por su interior, aumentando así la resistencia al flujo de sangre por su interior y disminuyendo la necesidad de reducir en una gran proporción el diámetro de la arteria pulmonar. With this configuration of the pin (5), there is a direct contact between the cylindrical side wall of the pin (5) and the blood vessel itself whose diameter is controlled. This contact causes a deformation of the blood vessel wall that helps modify the endoluminate laminar flow inside, thereby increasing the resistance to blood flow inside and decreasing the need to reduce in a large proportion the diameter of the pulmonary artery.
Así, para formar el lazo (3) sólo es necesario hacer pasar el extremo proximal de la cadena (2) de esferas a través del orificio (6) pasante transversal e introducir la última esfera proximal (2) en la cavidad. Se introducen entonces un par de tornillos a través de los respectivos extremos del orificio longitudinal desplazado en comunicación con la cavidad para atrapar dicha última esfera. Alternativamente, puede fijarse primero la esfera más proximal de la cadena (2) de esferas al pasador (5) con ayuda de los tornillos, y posteriormente hacer pasar el extremo distal de la cadena (2) de esferas a través del orificio (6) pasante haciendo que el vaso sanguíneo quede en el interior del lazo (3) formado. En cualquiera de los casos, para disminuir el diámetro del lazo (3) una vez formado, el profesional médico sólo tiene que tirar en sentido distal del extremo distal de la cadena (2), que de ese modo deslizará a través el orificio (6) pasante y disminuirá el diámetro del lazo (3). Thus, to form the loop (3) it is only necessary to pass the proximal end of the chain (2) of spheres through the transverse through hole (6) and introduce the last proximal sphere (2) into the cavity. A pair of screws are then introduced through the respective ends of the longitudinal hole displaced in communication with the cavity to trap said last sphere. Alternatively, the most proximal sphere of the chain (2) of spheres can be fixed first to the pin (5) with the help of the screws, and then pass the distal end of the chain (2) of spheres through the hole (6) through which the blood vessel is inside the loop (3) formed. In any case, to decrease the diameter of the loop (3) once formed, the medical professional only has to pull distally from the distal end of the chain (2), which will thus slide through the hole (6 ) through and the diameter of the loop (3) will decrease.
Por otra parte, en este ejemplo cuando se tira en sentido distal del extremo distal de la cadena (2) para disminuir el diámetro del lazo (3), el pasador (5) queda apoyado contra el extremo proximal (4p) del conducto (4). Esto impide que las tensiones se transmitan, evitando así que el vaso sanguíneo que se encuentra en el interior del lazo (3) resulte fraccionado. En este contexto, es importante que el extremo proximal (4p) del conducto (4) esté situado suficientemente cerca del vaso sanguíneo como para que el pasadorOn the other hand, in this example when the distal end of the chain (2) is pulled distally to decrease the diameter of the loop (3), the pin (5) is supported against the proximal end (4p) of the conduit (4) ). This prevents tensions from being transmitted, thus preventing the blood vessel inside the loop (3) from being fractionated. In this context, it is important that the proximal end (4p) of the duct (4) is located close enough to the blood vessel so that the pin
(5) esté en todo momento apoyado contra el extremo proximal (4p) del conducto (4). (5) is at all times leaning against the proximal end (4p) of the duct (4).
Caja (8) de almacenamiento Storage box (8)
La caja (8) de almacenamiento sirve para almacenar la porción distal (2d) de la cadena (2) de esferas. Esta porción distal (2d) debe tener una longitud suficiente como para permitir diferentes diámetros del lazo (3) ubicado en la porción proximal (2p) de dicha cadena (2) de esferas. Además, la caja (8) de almacenamiento debe ser completamente estanca, ya que quedará situada bajo la piel del paciente en contacto con diversos fluidos corporales durante un período de tiempo que puede ser bastante largo, del orden de varios meses o años. Para ello, como se aprecia en las Figs. 2a y 2b, la caja (8) de este ejemplo está formada por una tapa (8a) y una base (8b) que encajan herméticamente una con otra. Puede utilizarse uno o varios tornillos o similares para el acoplamiento seguro de tapa (8a) y base (8b). The storage box (8) serves to store the distal portion (2d) of the chain (2) of spheres. This distal portion (2d) must be of sufficient length to allow different diameters of the loop (3) located in the proximal portion (2p) of said chain (2) of spheres. In addition, the storage box (8) must be completely waterproof, as it will be located under the skin of the patient in contact with various body fluids for a period of time that can be quite long, of the order of several months or years. To do this, as seen in Figs. 2a and 2b, the box (8) of this example is formed by a cover (8a) and a base (8b) that fit tightly together. One or more screws or the like can be used for the secure coupling of cover (8a) and base (8b).
El interior de la base (8b) de la caja (8) de almacenamiento de este ejemplo está formado por un par de cavidades (1 1a, 1 1 b). La cavidad (1 1a) tiene un tamaño pequeño y fundamentalmente consiste simplemente en la continuación del orificio de entrada de la cadena (2) de esferas en la base (8b) de la caja (8) de almacenamiento. La cavidad (11 b) tiene un tamaño mayor que la anterior, ya que tiene la función de almacenar la porción distal (2d) de la cadena (2) de esferas. Entre la cavidad (11 a) y la cavidad (1 1 b) se ubica el medio (9) de fijación de la cadena (2) de esferas, que en este ejemplo está formado por un par de salientes (9a, 9b) enfrentados de modo que forman una ranura que comunica la cavidad (11 a) con la cavidad (1 1 b) y que está configurada para enganchar una esfera de la cadena (2) de esferas. La ranura tiene un tamaño tal que no permite el paso de una esfera completa de la cadena (2), pero sí el paso del vástago de unión entre esferas contiguas de la cadena (2). Por tanto, para fijar la cadena (2) de esferas en la posición deseada el usuario sólo tiene que empujar hacia abajo dos esferas contiguas de modo que queden a los respectivos lados de la ranura. Se coloca entonces la tapa (8a), cuya superficie de cierre queda esencialmente a ras de la parte superior de las cavidades (1 1a, 1 1 b), de modo que se cierra el extremo superior de la ranura y se impide que ninguna esfera pueda pasar de la cavidad (1 1 b) a la cavidad (1 1a). The interior of the base (8b) of the storage box (8) of this example is formed by a pair of cavities (1 1a, 1 1 b). The cavity (1 1a) has a small size and basically consists simply of the continuation of the entrance hole of the chain (2) of spheres in the base (8b) of the storage box (8). The cavity (11 b) is larger than the previous one, since it has the function of storing the distal portion (2d) of the chain (2) of spheres. Between the cavity (11 a) and the cavity (1 1 b) is located the means (9) for fixing the chain (2) of spheres, which in this example is formed by a pair of protrusions (9a, 9b) facing each other so that they form a groove that communicates the cavity (11 a) with the cavity (1 1 b) and that is configured to engage a sphere in the chain (2) of spheres. The groove has a size such that it does not allow the passage of a complete sphere of the chain (2), but the passage of the connecting rod between adjacent spheres of the chain (2). Therefore, to fix the chain (2) of spheres in the desired position, the user only has to push down two adjacent spheres so that they are on the respective sides of the groove. The cover (8a) is then placed, whose closing surface is essentially flush with the upper part of the cavities (1 1a, 1 1 b), so that the upper end of the groove is closed and no sphere is prevented can pass from the cavity (1 1 b) to the cavity (1 1a).
La base (1 1a) de la caja (8) de almacenamiento tiene además un saliente (10) exterior ubicado en la posición del orificio de entrada de la cadena (2) en la caja (8) que tiene una forma esencialmente cilindrica aunque dotada de una conicidad externa. De manera general, esta conicidad permite la fijación del conducto (4) a presión. Más concretamente, en el caso de este ejemplo donde el conducto (4) está formado por un conducto interior (4i) y un conducto exterior (4e), es el conducto exterior (4e) el que se acopla al saliente (10). Una vez el conducto exterior (4e) se ha acoplado a dicho saliente (10), puede introducirse en su interior el conducto (4i) hasta que su extremo distal se apoya contra los bordes del saliente (10). El conducto interior (4i) además debe sobresalir por el extremo proximal del conducto exterior (4e). De este modo se evita que las esferas de la cadena (2) de esferas puedan engancharse en los bordes del saliente (10) o bien en los bordes del extremo proximal del conducto exterior (4e) debido a su diámetro interior excesivamente holgado para las esferas de la cadena (2). Por último, la Fig. 5 muestra esquemáticamente un conjunto (10) de partes para el control de flujo de sangre en un vaso sanguíneo formado por una cadena (2) de esferas, un pasador (5) y una caja (8) de almacenamiento, que en este ejemplo está formada por una base (8a) y una tapa (8b). Este conjunto (10) de partes puede suministrarse en una bolsa u otro envase para que el usuario monte el dispositivo (1) durante el propio procedimiento quirúrgico, utilizando uno o varios catéteres de un diámetro adecuado para implementar el conducto (4). The base (1 1a) of the storage box (8) also has an outer projection (10) located in the position of the chain inlet hole (2) in the box (8) which has an essentially cylindrical shape although provided of an external conicity. In general, this conicity allows the fixing of the conduit (4) under pressure. More specifically, in the case of this example where the duct (4) is formed by an inner duct (4i) and an outer duct (4e), it is the outer duct (4e) that is coupled to the outgoing (10). Once the outer conduit (4e) has been coupled to said projection (10), the conduit (4i) can be introduced inside it until its distal end is supported against the edges of the projection (10). The inner duct (4i) must also protrude from the proximal end of the outer duct (4e). In this way it is avoided that the spheres of the chain of spheres (2) can catch on the edges of the projection (10) or on the edges of the proximal end of the outer conduit (4e) due to its excessively loose inner diameter for the spheres of the chain (2). Finally, Fig. 5 schematically shows a set (10) of parts for the control of blood flow in a blood vessel formed by a chain (2) of spheres, a pin (5) and a storage box (8) , which in this example is formed by a base (8a) and a cover (8b). This set (10) of parts can be supplied in a bag or other container for the user to mount the device (1) during the surgical procedure itself, using one or more catheters of a suitable diameter to implement the conduit (4).
Experimentos con modelo animal Con el fin de evaluar el dispositivo de la invención, se desarrolló un modelo animal de tamaño y peso similar al de los pacientes de nuestra población objeto, concretamente conejos macho de la raza New Zealand. Es importante resaltar algunas situaciones que se produjeron durante el implante y ajuste del dispositivo: · La monitorización del animal no presento ningún tipo de inconveniente, permitiendo verificar su frecuencia cardiaca, frecuencia respiratoria, saturación de oxígeno y trazo electrocardiográfico de manera adecuada. Experiments with animal model In order to evaluate the device of the invention, an animal model of size and weight similar to that of the patients of our target population, specifically male rabbits of the New Zealand breed, was developed. It is important to highlight some situations that occurred during the implant and adjustment of the device: · The animal monitoring did not present any type of inconvenience, allowing to verify its heart rate, respiratory rate, oxygen saturation and electrocardiographic stroke in an adequate way.
• A nivel anestésico, la intubación fue un poco difícil, pero una vez conseguida, el animal se adaptó adecuadamente a la ventilación mecánica bajo volumen control.  • At the anesthetic level, intubation was a bit difficult, but once achieved, the animal adapted properly to mechanical ventilation under control volume.
• La anatomía de la caja torácica fue un gran reto, porque son roedores con un tórax en quilla, el esternón es casi inexistente y sus costillas son muy frágiles y con muy poco espacio entre ellas. Se decidió realizar una esternotomía media por la mejor exposición anatómica. • El corazón y las arterias principales son muy pequeñas, requiriendo un gran cuidado y control durante todo el proceso. • The anatomy of the rib cage was a great challenge, because they are rodents with a keel thorax, the sternum is almost non-existent and its ribs are very fragile and with very little space between them. It was decided to perform a medium sternotomy for the best anatomical exposure. • The heart and main arteries are very small, requiring great care and control throughout the process.
• El trabajar sobre corazones normales, sin ningún tipo de cardiopatía estructural (confirmado por las ecocardiografías básales realizadas antes de la cirugía) añadía un grado de dificultad mayor, porque se creó una sobrecarga de presión aguda sobre el ventrículo derecho, con el riesgo de generar una insuficiencia aguda o arritmias malignas. Por ello, el procedimiento fue lento hasta conseguir un grado de tolerancia del ventrículo.  • Working on normal hearts, without any structural heart disease (confirmed by baseline echocardiography performed before surgery) added a greater degree of difficulty, because an acute pressure overload on the right ventricle was created, with the risk of generating acute insufficiency or malignant arrhythmias. Therefore, the procedure was slow to achieve a degree of ventricle tolerance.
· En los animales en los que se completó la intervención quirúrgica, el cierre del esternón no fue tan difícil como se creía al principio. Se pudo realizar un cierre hermético, cicatrizo rápidamente y no generó problemas ventilatorios en el postoperatorio.  · In the animals in which the surgical intervention was completed, the closure of the sternum was not as difficult as initially believed. It was possible to perform a hermetic closure, heal quickly and did not generate ventilatory problems in the postoperative period.
• La cirugía de ajuste de dispositivo, fue rápida y fácil de realizar.  • The device adjustment surgery was quick and easy to perform.
« La ecogenicidad de las esferas permitieron facilitaron el seguimiento y control por ecocardiografía.  «The echogenicity of the spheres allowed to facilitate the monitoring and control by echocardiography.
Las dimensiones del dispositivo implantado fueron en todos los casos de 10 centímetros con un número total de 52 esferas de 19 mm de diámetro. A continuación, se presenta la Tabla 1 donde se indica la modificación teóricamente esperable en el diámetro, perímetro y superficie del lazo del dispositivo utilizado en función del número de esferas de desplazamiento de su extremo distal. Estos datos se contrastarán durante este experimento con los valores obtenidos por ecocardiografía. Tabla 1 The dimensions of the implanted device were in all cases 10 centimeters with a total number of 52 spheres of 19 mm in diameter. Next, Table 1 is presented where the theoretically expected modification in the diameter, perimeter and surface of the loop of the device used is indicated based on the number of displacement spheres of its distal end. These data will be contrasted during this experiment with the values obtained by echocardiography. Table 1
Figure imgf000018_0001
Figure imgf000019_0001
Figure imgf000018_0001
Figure imgf000019_0001
Se trató de implantar este dispositivo en cuatro animales. Dos animales murieron durante el procedimiento de implante del dispositivo, de modo que sólo se consiguió implantar el dispositivo en dos animales. En los dos animales que superaron la operación de implante se intentó disminuir el diámetro de la arteria pulmonar vigilando visualmente al mismo tiempo la función del ventrículo derecho, la saturación de oxígeno y la frecuencia cardiaca. Solo uno de los animales sobrevivió a todo el proceso, como se describirá a continuación. It was tried to implant this device in four animals. Two animals died during the device implant procedure, so that the device was only implanted in two animals. In the two animals that surpassed the implant operation, an attempt was made to reduce the diameter of the pulmonary artery while visually monitoring the function of the right ventricle, oxygen saturation and heart rate. Only one of the animals survived the entire process, as will be described below.
La Tabla 2 muestra las medidas anatómicas y hemodinámicas de los conejos utilizados en este experimento durante el procedimiento quirúrgico. Table 2 shows the anatomical and hemodynamic measurements of the rabbits used in this experiment during the surgical procedure.
DTA PTA LTA PTA PA SaO NE NE DTA PTA LTA PTA PA SaO NE NE
Conejo P P P PVD P O 2 FI02 FC LB DB PB AP C SV Causa  Rabbit P P P PVD P O 2 FI02 FC LB DB PB AP C SV Cause
II: SI: wm m II mm. Arritmia: II: YES: wm m II mm. Arrhythmia:
20 16 37 98 40 180 10 NO Sangrado mm m 11 wm mm m m m mmmrn20 16 37 98 40 180 10 NO Bleeding mm m 11 wm mm m m m mmmrn
22 20 8 11 33 99 40 180 10 6,5 20,5 24 SI 22 20 8 11 33 99 40 180 10 6.5 20.5 24 YES
Media [ 6.38 [ 20.5 | 17 | β [ 9.5 1 3i  Mean [6.38 [20.5 | 17 | β [9.5 1 3i
DTAP: Diámetro del tronco de la arteria pulmonar;  DTAP: Diameter of the pulmonary artery trunk;
PTAP: Perímetro del arteria pulmonar;  PTAP: Perimeter of the pulmonary artery;
LTAP: Longitud del tronco de la arteria pulmonar;  LTAP: Length of the trunk of the pulmonary artery;
PVD: Presión ventrículo derecho;  PVD: Right ventricle pressure;
PTAP: Presión tronco de la arteria pulmonar;  PTAP: Lung artery trunk pressure;
PAO: Presión Aórtica;  PAO: Aortic Pressure;
Sa02: Saturación arterial de oxígeno;  Sa02: arterial oxygen saturation;
FI02: Fracción inspirada de oxígeno;  FI02: Inspired oxygen fraction;
FC: Frecuencia cardiaca;  FC: Heart rate;
LB: Longitud del banding;  LB: Banding Length;
DB: Diámetro del banding;  DB: Banding diameter;
PB: Perímetro del banding alrededor de la arteria pulmonar;  PB: Banding perimeter around the pulmonary artery;
NEAP: Número de esferas alrededor de la arteria pulmonar;  NEAP: Number of spheres around the pulmonary artery;
NEC: Número de esferas en la caja;  NEC: Number of spheres in the box;
SV: Supervivencia;  SV: Survival;
FVD: Fallo Ventricular derecho;  FVD: Right Ventricular Failure;
NT: Neumotorax.  NT: Pneumothorax.
A continuación, se describe brevemente el resultado de las intervenciones realizadas a cada uno de los animales. The result of the interventions performed on each animal is briefly described below.
Conejo 1 Rabbit 1
Durante la manipulación de la arteria pulmonar, presentó una fibrilación ventricular que no respondió a maniobras de resucitación y el animal muere. Conejo 2 During the manipulation of the pulmonary artery, he presented a ventricular fibrillation that did not respond to resuscitation maneuvers and the animal dies. Rabbit 2
La arteria pulmonar se desgarra en la cara posterior durante su disección, pero aún así se consiguió reparar el daño. El animal sufrió un sangrado importante, pero se administró suero fisiológico a través del ventrículo izquierdo y se logró su estabilización. Se decidió cerrar el tórax e intentar de nuevo la implantación del dispositivo cuando los tejidos hubiesen cicatrizado, pero el animal fallece a los tres días por anemia. The pulmonary artery tears in the posterior aspect during dissection, but the damage was still repaired. The animal suffered significant bleeding, but physiological serum was administered through the left ventricle and stabilization was achieved. It was decided to close the chest and try again the implantation of the device when the tissues had healed, but the animal dies after three days due to anemia.
Conejo 3 Rabbit 3
Durante la intervención quirúrgica no hubo problemas y se logró implantar adecuadamente el dispositivo. El animal toleró un pequeño estrechamiento de la arteria pulmonar, exactamente 1 ,5 milímetros (2 esferas aproximadamente) lo que corresponde a un 23% del diámetro del lazo del dispositivo. Una vez terminada la intervención, se retiró el tubo orotraqueal y se vigiló su estado en el área de recuperación, pero a la hora del postoperatorio realizó una apnea súbita, con un trazo electrocardiográfico rítmico de taquicardia de 250 latidos por minuto. Se realizaron medidas de reanimación pero no respondió y finalmente muere. Se reabrió el tórax y no se encontraron signos de sangrado, ni distorsión de la arteria pulmonar. Se concluyó que probablemente la muerte se debió a un fallo ventricular derecho por hipertensión pulmonar aguda o un neumotorax. Conejo 4 During the surgical intervention there were no problems and the device was properly implanted. The animal tolerated a small narrowing of the pulmonary artery, exactly 1.5 millimeters (approximately 2 spheres) which corresponds to 23% of the diameter of the device loop. Once the intervention was over, the orotracheal tube was removed and its status was monitored in the recovery area, but at the time of the postoperative period, she performed a sudden apnea, with a rhythmic electrocardiographic tachycardia stroke of 250 beats per minute. Resuscitation measures were taken but he did not respond and eventually dies. The chest was reopened and no signs of bleeding or distortion of the pulmonary artery were found. It was concluded that death was probably due to a right ventricular failure due to acute pulmonary hypertension or pneumothorax. Rabbit 4
Al igual que el conejo 3, se implantó el dispositivo sin complicaciones y se consiguió estrechar la arteria pulmonar. Teniendo en cuenta lo sucedido con el conejo anterior, esta vez solo se cerraron 0,5 milímetros de diámetro aproximadamente (1 esfera), lo que corresponde a un 7% del diámetro del lazo del dispositivo. El animal superó adecuadamente el postoperatorio inicial, toleró la vía oral a las 6 horas y evolucionó satisfactoriamente. Se pudieron realizar múltiples ecocardiografías de control y ajusfar el diámetro del lazo del dispositivo, todo esto llevado a cabo en un periodo total de 24 días. Se realizaron dos ajustes del diámetro del lazo del dispositivo sin dificultades y bajo control ecocardiográfico simultaneo. El primer ajuste consistió en una disminución del diámetro del lazo a través del desplazamiento de dos esferas en sentido distal, lo que significa una reducción de 1 ,3 milímetros aproximadamente. El segundo ajuste consistió en un aumento del diámetro del lazo del dispositivo para recuperar su diámetro inicial, es decir, se desplazaron dos esferas en sentido proximal. Like rabbit 3, the device was implanted without complications and the pulmonary artery was narrowed. Taking into account what happened with the previous rabbit, this time only about 0.5 millimeters in diameter (1 sphere) were closed, which corresponds to 7% of the device's loop diameter. The animal adequately exceeded the initial postoperative period, tolerated the oral route at 6 hours and evolved satisfactorily. Multiple control echocardiograms could be performed and the diameter of the device loop adjusted, all this carried out in a total period of 24 days. Two adjustments of the diameter of the device loop were made without difficulties and under simultaneous echocardiographic control. The first adjustment consisted of a decrease in the diameter of the loop through the displacement of two spheres distally, which means a reduction of approximately 1.3 millimeters. The second adjustment consisted of an increase in the loop diameter of the device to recover its initial diameter, that is, two spheres were displaced proximally.
Evaluación ecocardiográfica Se realizó una ecocardiografía basal a los 4 conejos, previa a la intervención, con el fin de conocer el estado de su función cardiaca, las dimensiones anatómicas y la presencia de shunts por malformaciones. Los resultados se muestran en la Tabla 3. Echocardiographic evaluation A baseline echocardiography was performed on the 4 rabbits, prior to the intervention, in order to know the status of their cardiac function, anatomical dimensions and the presence of shunts due to malformations. The results are shown in Table 3.
Tabla 3 Table 3
Figure imgf000021_0001
Figure imgf000021_0001
AFVI: Acortamiento fraccional del ventrículo izquierdo;  AFVI: Fractional shortening of the left ventricle;
DTAP: Diámetro del tronco principal de la arteria pulmonar;  DTAP: Diameter of the main trunk of the pulmonary artery;
DRPD: Diámetro Rama pulmonar derecha; DRPI: Diámetro de la rama pulmonar izquierda;  DRPD: Right pulmonary branch diameter; DRPI: Diameter of the left pulmonary branch;
LVB: Longitud válvula-bifurcación;  LVB: Valve-fork length;
DVP: Diámetro válvula pulmonar;  DVP: Pulmonary valve diameter;
FC: Frecuencia cardiaca;  FC: Heart rate;
Sa02: Saturación arterial de oxígeno;  Sa02: arterial oxygen saturation;
GAP: Gradiente de la arteria pulmonar;  GAP: Gradient of the pulmonary artery;
MC: Malformaciones cardiacas.  MC: Cardiac malformations.
Con el conejo 4, superviviente de la intervención quirúrgica, se realizaron 6 ecocardiografías de control del dispositivo, evaluando su función, ajuste, estabilidad a corto plazo y posible migración. Las dimensiones anatómicas encontradas estas ecocardiografías son equivalentes a las que se aprecian durante la cirugía realizada para el implante del dispositivo, lo que añade fiabilidad a este método de seguimiento. Los datos obtenidos en las ecocardiografías realizadas el conejo 4 se muestran en la Tabla 4. Tabla 4 With rabbit 4, survivor of the surgical intervention, 6 echocardiographs were performed to control the device, evaluating its function, adjustment, short-term stability and possible migration. The anatomical dimensions found in these echocardiographies are equivalent to those seen during the surgery performed for the implant of the device, which adds reliability to this monitoring method. The data obtained on the echocardiography performed on rabbit 4 are shown in Table 4. Table 4
Figure imgf000022_0001
Figure imgf000022_0001
Los datos obtenidos por las ecocardiografías de la Tabla 4 muestran que no se produjo ninguna migración apreciable del dispositivo, ya que las distancias entre la válvula y el dispositivo, así como entre el dispositivo y la bifurcación pulmonar, se mantuvieron estables. De la misma forma, no se registraron gradientes a nivel de las ramas pulmonares. Tampoco se identificaron cambios en el diámetro del dispositivo con el paso de los días, manteniendo su estabilidad a pesar de la presión pulmonar y los movimientos del animal. Además, se comprueba que los cambios de diámetro del dispositivo vistos por ecocardiografía se correlacionan estrechamente con los datos ofrecidos por la tabla de modificación del diámetro según número de esferas (Tabla 1). The data obtained by the echocardiographs in Table 4 show that there was no appreciable migration of the device, since the distances between the valve and the device, as well as between the device and the pulmonary bifurcation, remained stable. In the same way, no gradients were registered at the level of the pulmonary branches. Nor were changes in the diameter of the device identified over the days, maintaining its stability despite pulmonary pressure and animal movements. In addition, it is verified that the changes in device diameter seen by echocardiography are closely correlated with the data offered by the diameter modification table according to number of spheres (Table 1).
Como se mencionó anteriormente, se realizaron dos modificaciones del diámetro del dispositivo de la invención. La primera modificación consistió en la disminución del diámetro del lazo y la segunda modificación consistió en el aumento del diámetro del lazo hasta volver a su diámetro inicial. Como era de esperar, la disminución de diámetro del lazo del dispositivo provocó un aumento de las velocidades y los gradientes, y el aumento del diámetro del diámetro del lazo provocó una disminución de las velocidades y los gradientes. Esto se aprecia mejor en la Tabla 5, que muestra los datos ecocardiográficos función del dispositivo de la invención. Tabla 5 As mentioned above, two modifications of the diameter of the device of the invention were made. The first modification consisted of the decrease of the diameter of the loop and the second modification consisted of the increase of the diameter of the loop until returning to its initial diameter. As expected, the decrease in loop diameter of the device caused an increase in speeds and gradients, and the increase in diameter of the loop diameter caused a decrease in speeds and gradients. This is best seen in Table 5, which shows the echocardiographic data depending on the device of the invention. Table 5
Figure imgf000023_0001
Figure imgf000023_0001
Además, la Fig. 6 muestra un gráfico de los cambios en el gradiente, velocidad y diámetro a lo largo de las ecocardiografías de control realizadas.  In addition, Fig. 6 shows a graph of the changes in the gradient, velocity and diameter along the control echocardiograms performed.
El día 24 se realizó el sacrificio del animal y se evaluó el estado de los tejidos y el dispositivo. El dispositivo seguía en la misma posición en que fue implantado, con escasas adhesiones de los tejidos a la cadena. La pared de la arteria pulmonar se encontraba en buen estado y sin signos de necrosis macroscópica. La cadena estaba sin signos de deterioro o daño, pero los tubos de silicona que usamos perdieron cierto grado de elasticidad. On day 24 the animal was sacrificed and the condition of the tissues and the device was evaluated. The device was still in the same position in which it was implanted, with few adhesions of the tissues to the chain. The pulmonary artery wall was in good condition and with no signs of macroscopic necrosis. The chain was without signs of deterioration or damage, but the silicone tubes we used lost some degree of elasticity.
Conclusiones Se ha tratado de crear un modelo animal lo más parecido a la realidad, y por ese motivo se eligió un animal de experimentación de pequeño tamaño. Además, se pensó en realizar algún tipo de modificación al corazón de los animales para crear de alguna manera una sobrecarga de flujo en la arteria pulmonar, pero se concluyó que los objetivos de este proyecto podrían ser alcanzados sobre un corazón normal, asumiendo el riesgo de una falla cardiaca intolerable durante el postoperatorio. La complejidad del modelo de experimentación solo permitió evaluar el funcionamiento del dispositivo en uno de los cuatro conejos. Sin embargo, esto ha sido suficiente para demostrar la función mecánica y de ajuste del dispositivo. Se ha modificado en dos ocasiones el diámetro de la arteria pulmonar, guiado por ecocardiografía simultánea, desde fuera de la cavidad torácica, sobre un corazón estructuralmente normal y en un animal de 3,430 gramos de peso. Conclusions An attempt has been made to create an animal model that is closest to reality, and for this reason a small experimental animal was chosen. In addition, it was thought to make some type of modification to the heart of the animals to somehow create an overload of flow in the pulmonary artery, but it was concluded that the objectives of this project could be achieved over a normal heart, assuming the risk of an intolerable heart failure during the postoperative period. The complexity of the experimentation model only allowed to evaluate the operation of the device in one of the four rabbits. However, this has been sufficient to demonstrate the mechanical and adjustment function of the device. The diameter of the pulmonary artery, guided by simultaneous echocardiography, from outside the thoracic cavity, over a structurally normal heart and in an animal weighing 3,430 grams has been modified twice.
El uso de la ecocardiografía fue una herramienta fundamental, con ella se evaluó la anatomía y función basal de todos los animales. Se comprobó que el dispositivo ajustable de la invención modificó de manera adecuada el diámetro de la arteria pulmonar tanto en el momento del implante como en posteriores ajustes, y se evaluaron los cambios de velocidad y gradiente sufridos. La tabla de ajuste del diámetro según el número de esferas (Tabla 1) es una herramienta muy útil y se comprobó que sus datos se correlacionan estrechamente con la ecocardiografía. En el hipotético caso de no contar con un equipo de ecocardiografía, esto permitirá realizar modificaciones del dispositivo con seguridad. Los gradientes de presión post-banding, una vez realizado el ajuste de apertura, descendieron inmediatamente casi hasta los valores básales. Sin embargo, resulta curioso que después de 7 días estos gradientes ascendieron ligeramente en vez de descender. Esto podría estar justificado por la hipertrofia ventricular derecha sufrida como adaptación a la sobrecarga de presión. Se decidió continuar con el protocolo diseñado previamente y no se evaluó si estos valores cambiaban con el tiempo. The use of echocardiography was a fundamental tool, with it the anatomy and baseline function of all animals was evaluated. It was found that the adjustable device of the invention adequately modified the diameter of the pulmonary artery both at the time of implantation and subsequent adjustments, and the changes in speed and gradient suffered were evaluated. The diameter adjustment table according to the number of spheres (Table 1) is a very useful tool and its data was found to correlate closely with echocardiography. In the hypothetical case of not having an echocardiography device, this will allow modifications of the device safely. The post-banding pressure gradients, once the opening adjustment was made, immediately descended almost to the baseline values. However, it is curious that after 7 days these gradients rose slightly instead of descending. This could be justified by the right ventricular hypertrophy suffered as an adaptation to pressure overload. It was decided to continue with the previously designed protocol and it was not evaluated whether these values changed over time.
Los datos de dilatación de la arteria pulmonar a nivel pre y postbanding se pueden relacionar con el proceso de adaptación de la pared vascular a la sobrecarga de presión que se efectuó sobre un corazón sano. Se desconoce si esto cambia con el paso del tiempo. The pulmonary artery dilation data at the pre and postbanding levels can be related to the process of adapting the vascular wall to the pressure overload that was carried out on a healthy heart. It is unknown if this changes over time.
La evidencia de no migración del dispositivo y el mantener su estabilidad es un dato muy importante, a pesar que fueron evaluadas en un solo animal, a corto plazo y con presiones de un corazón normal, ya que nos permite deducir que el dispositivo podría superar dos de las más comunes complicaciones de los dispositivos de banding convencionales y de los banding ajustables diseñados. The evidence of non-migration of the device and maintaining its stability is a very important fact, although they were evaluated in a single animal, in the short term and with pressures of a normal heart, since it allows us to deduce that the device could overcome two of the most common complications of conventional banding devices and designed adjustable banding.
Durante la intervención quirúrgica, se observó que si la caja de almacenamiento sufre algún tipo de giro, existe un riesgo de acodamiento de la arteria pulmonar. Esto se solucionó colocando un punto de fijación sobre la caja a la los músculos en la primera intervención. En las cirugías de ajuste no fue necesario colocar ningún punto, ya que los tejidos alrededor la mantenían en su lugar. Se comprobó además que no es necesario el empleo de dos conductos, un conducto interior y un conducto exterior, sino que basta con un único conducto o tubo. En el sacrificio del animal se observó que los tubos de silicona que usamos perdieron cierto grado de elasticidad, pero esto es algo que se puede solucionar usando tubos flexibles de mayor calidad y durabilidad. During the surgical intervention, it was observed that if the storage box undergoes some type of rotation, there is a risk of cranial pulmonary artery. This was solved by placing a fixation point on the box to the muscles in the first intervention. In the setting surgeries it was not necessary to place any stitches, since the surrounding tissues held it in place. It was also found that it is not necessary to use two ducts, an inner duct and an outer duct, but only a single duct or tube is sufficient. In the animal sacrifice it was observed that the silicone tubes we use lost a certain degree of elasticity, but this is something that can be solved using flexible tubes of higher quality and durability.
Consideramos que los resultados de nuestra supervivencia, se debe a la complejidad del procedimiento en este grupo de animales y a la curva de aprendizaje, a pesar de esto, consideramos que es una técnica reproducible. Mejoras en el dispositivo We consider that the results of our survival are due to the complexity of the procedure in this group of animals and the learning curve, despite this, we consider it a reproducible technique. Device Enhancements
Como consecuencia de la experiencia adquirida gracias a la experimentación anterior, se proponen una serie de cambios y mejoras con relación al dispositivo descrito inicialmente en este documento. As a consequence of the experience acquired thanks to previous experimentation, a series of changes and improvements are proposed in relation to the device initially described in this document.
En una realización preferida adicional, el conducto (4), el pasador (5) y el extremo proximal de la cadena (2) están unidos formando una única pieza. Esto permitirá realizar la instalación y desinstalación del dispositivo (1) sin necesidad de abrir el tórax, por ejemplo a través de un dispositivo laparoscópico adecuado. In a further preferred embodiment, the conduit (4), the pin (5) and the proximal end of the chain (2) are joined forming a single piece. This will allow the installation and uninstallation of the device (1) without opening the chest, for example through a suitable laparoscopic device.
En otra realización preferida adicional, la caja (8) de almacenamiento tiene un orificio adicional de salida de la porción distal (2d) de la cadena (2). Este orificio adicional de salida permitirá que la porción distal (2d) de la cadena sobresalga fuera de la caja (8) y quede flotante fuera de la misma. Esto no debe representar un problema, dado que la cadena (2) está hecha de un material biocompatible. Con esta configuración, ya no es necesario que la caja (8) almacene toda la porción distal (2d) de la cadena (2), con lo que se podrá disminuir su tamaño. A este respecto, nótese que el tamaño de la caja (8) deberá en cualquier caso ser suficiente para alojar el medio (9) de fijación de la cadena (2), y al mismo tiempo ser suficiente como para que ésta ejerza a modo de "ancla" que evite la migración del dispositivo (1) por el interior del cuerpo del paciente. In another additional preferred embodiment, the storage box (8) has an additional outlet port of the distal portion (2d) of the chain (2). This additional exit hole will allow the distal portion (2d) of the chain to protrude out of the box (8) and float out of it. This should not represent a problem, since the chain (2) is made of a biocompatible material. With this configuration, it is no longer it is necessary for the box (8) to store the entire distal portion (2d) of the chain (2), so that its size can be reduced. In this regard, it should be noted that the size of the box (8) must in any case be sufficient to accommodate the means (9) for fixing the chain (2), and at the same time be sufficient for it to exercise as a "anchor" that prevents the migration of the device (1) inside the patient's body.
En los experimentos descritos el diámetro de las esferas de la cadena fue de 19 mm. Sin embargo, se comprueba que es posible disminuir aún más este diámetro. La disminución del diámetro de las esferas tiene la ventaja de que el desplazamiento de una esfera en sentido proximal o distal provoca menores disminuciones del diámetro del lazo, con lo que es posible ajusfar éste de una manera más precisa. Por lo tanto, de acuerdo con realizaciones preferidas de la invención, el diámetro del lazo será de entre 5 mm y 20 mm, y más preferentemente de entre 10 mm y 15 mm. In the experiments described, the diameter of the chain spheres was 19 mm. However, it is found that it is possible to further decrease this diameter. The decrease in the diameter of the spheres has the advantage that the displacement of a sphere in the proximal or distal direction causes smaller decreases in the diameter of the loop, with which it is possible to adjust it more precisely. Therefore, according to preferred embodiments of the invention, the diameter of the loop will be between 5 mm and 20 mm, and more preferably between 10 mm and 15 mm.

Claims

REIVINDICACIONES
1. Dispositivo (1) de control de flujo de sangre en un vaso sanguíneo, caracterizado por que comprende una cadena (2) formada por eslabones donde el ángulo máximo de giro entre cada par de eslabones está limitado, donde la cadena (2) tiene una porción proximal (2p) dotada de un lazo (3) configurado para rodear el vaso sanguíneo con el propósito de comprimirlo y una porción distal (2d) configurada para cerrar el lazo (3) mediante la aplicación de tracción. 1. Blood flow control device (1) in a blood vessel, characterized in that it comprises a chain (2) formed by links where the maximum angle of rotation between each pair of links is limited, where the chain (2) has a proximal portion (2p) provided with a loop (3) configured to surround the blood vessel for the purpose of compressing it and a distal portion (2d) configured to close the loop (3) by the application of traction.
2. Dispositivo (1) de acuerdo con la reivindicación 1 , donde los eslabones que conforman la cadena (2) son esferas. 2. Device (1) according to claim 1, wherein the links that make up the chain (2) are spheres.
3. Dispositivo (1) de acuerdo con la reivindicación 2, donde el diámetro de las esferas es de entre 5 mm y 20 mm. 3. Device (1) according to claim 2, wherein the diameter of the spheres is between 5 mm and 20 mm.
4. Dispositivo (1) de acuerdo con la reivindicación 3, donde el diámetro de las esferas es de entre 10 mm y 15 mm. 4. Device (1) according to claim 3, wherein the diameter of the spheres is between 10 mm and 15 mm.
5. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones anteriores, que además comprende: 5. Device (1) according to any of the preceding claims, further comprising:
un conducto (4) que tiene un extremo distal (4d) configurado para situarse esencialmente bajo a la piel del paciente y un extremo proximal (4p) configurado para ubicarse junto al vaso sanguíneo,  a conduit (4) having a distal end (4d) configured to be essentially low to the patient's skin and a proximal end (4p) configured to be located next to the blood vessel,
de modo que la cadena (2) recorre el conducto (4) desde su extremo distal (4d) hasta su extremo proximal (4p), sobresaliendo la cadena (2) por el extremo proximal (4p) del conducto (4) de modo que forma el lazo (3) configurado para rodear el vaso sanguíneo,  so that the chain (2) runs through the conduit (4) from its distal end (4d) to its proximal end (4p), the chain (2) protruding from the proximal end (4p) of the conduit (4) so that form the loop (3) configured to surround the blood vessel,
y donde el lazo (3) está configurado para cerrarse mediante la aplicación de tracción a la cadena (2) desde el extremo distal (4d) del conducto (4).  and where the loop (3) is configured to close by applying traction to the chain (2) from the distal end (4d) of the conduit (4).
6. Dispositivo (1) de acuerdo con la reivindicación 5, que además comprende un pasador (5) solidario al extremo proximal (4p) del conducto (4) configurado para formar el lazo (3) de la cadena (2). 6. Device (1) according to claim 5, further comprising a pin (5) integral with the proximal end (4p) of the conduit (4) configured to form the loop (3) of the chain (2).
7. Dispositivo (1) de acuerdo con la reivindicación 6, donde el pasador (5) comprende un saliente esencialmente cilindrico configurado para acoplarse al extremo proximal del conducto (4). 7. Device (1) according to claim 6, wherein the pin (5) It comprises an essentially cylindrical projection configured to engage the proximal end of the conduit (4).
8. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones 6-7, donde el pasador (5) comprende un orificio (6) pasante configurado para el paso de la cadena8. Device (1) according to any of claims 6-7, wherein the pin (5) comprises a through hole (6) configured for the passage of the chain
(2) y un elemento (7) de fijación del extremo proximal (2p) de la cadena (2). (2) and a fastener (7) for fixing the proximal end (2p) of the chain (2).
9. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones 6-8, donde el conducto (4), el pasador (5) y el extremo proximal (2p) de la cadena (2) están unidos formando una única pieza. 9. Device (1) according to any of claims 6-8, wherein the conduit (4), the pin (5) and the proximal end (2p) of the chain (2) are joined forming a single piece.
10. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones 5-9, que además comprende una caja (8) de almacenamiento conectable al extremo distal (4d) del conducto (4) para el almacenamiento de la porción distal (2d) de la cadena (2). 10. Device (1) according to any of claims 5-9, further comprising a storage box (8) connectable to the distal end (4d) of the conduit (4) for storage of the distal portion (2d) of the chain (2).
1 1. Dispositivo (1) de acuerdo con la reivindicación 10, donde la caja (8) de almacenamiento comprende un medio (9) de fijación de la cadena (2). 1 Device (1) according to claim 10, wherein the storage box (8) comprises a means (9) for fixing the chain (2).
12. Dispositivo (1) de acuerdo con la reivindicación 1 1 , donde el medio (9) de fijación de la cadena (2) está formado por un par de salientes (9a, 9b) enfrentados de modo que forman una ranura configurada para enganchar un eslabón de la cadena (2). 12. Device (1) according to claim 1, wherein the means (9) for fixing the chain (2) is formed by a pair of projections (9a, 9b) facing so that they form a groove configured to engage a link in the chain (2).
13. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones 10-12, donde la conexión entre la caja (8) de almacenamiento y el conducto (4) es separable. 13. Device (1) according to any of claims 10-12, wherein the connection between the storage box (8) and the conduit (4) is separable.
14. Dispositivo (1) de acuerdo con la reivindicación 13, donde la conexión entre la caja (8) de almacenamiento y el conducto (4) comprende un saliente (10) esencialmente cilindrico que sobresale de un orificio de entrada de la caja (8) de almacenamiento y que está configurado para acoplarse al extremo distal (4d) del conducto (4). 14. Device (1) according to claim 13, wherein the connection between the storage box (8) and the conduit (4) comprises an essentially cylindrical projection (10) protruding from an inlet opening of the box (8) ) of storage and that is configured to engage the distal end (4d) of the conduit (4).
15. Dispositivo (1) de acuerdo con la reivindicación 14, donde el saliente (10) esencialmente cilindrico presenta una conicidad externa para el acoplamiento del extremo (4d) distal del conducto (4). 15. Device (1) according to claim 14, wherein the essentially cylindrical projection (10) has an external taper for coupling the distal end (4d) of the conduit (4).
16. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones 10-15, donde la caja (8) de almacenamiento tiene un orificio adicional de salida de la porción distal (2d) de la cadena (2). 16. Device (1) according to any of claims 10-15, wherein the storage box (8) has an additional outlet port of the distal portion (2d) of the chain (2).
17. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones anteriores, donde el conducto (4) está formado por la combinación de un conducto exterior (4e) y un conducto (4i) interior que sobresale proximalmente de dicho conducto exterior (4e). 17. Device (1) according to any of the preceding claims, wherein the conduit (4) is formed by the combination of an outer duct (4e) and an inner duct (4i) protruding proximally from said outer duct (4e) .
18. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones anteriores, donde la cadena (2) comprende un recubrimiento exterior flexible. 18. Device (1) according to any of the preceding claims, wherein the chain (2) comprises a flexible outer coating.
19. Dispositivo (1) de acuerdo con la reivindicación 18, donde el recubrimiento exterior es de silicona. 19. Device (1) according to claim 18, wherein the outer coating is silicone.
20. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones anteriores, donde la cadena (2) está hecha de un material metálico. 20. Device (1) according to any of the preceding claims, wherein the chain (2) is made of a metallic material.
21. Dispositivo (1) de acuerdo con cualquiera de las reivindicaciones anteriores, donde los eslabones de la porción distal (2d) de la cadena (2) comprenden unos marcadores visibles por ultrasonografía que indican el diámetro del lazo (3). 21. Device (1) according to any of the preceding claims, wherein the links of the distal portion (2d) of the chain (2) comprise markers visible by ultrasonography indicating the diameter of the loop (3).
22. Conjunto (10) de partes para el control de flujo de sangre en un vaso sanguíneo con ayuda de un conducto (4), caracterizado por que comprende: 22. Set (10) of parts for the control of blood flow in a blood vessel with the aid of a conduit (4), characterized in that it comprises:
- una cadena (2) formada por eslabones donde el ángulo máximo de giro entre cada par de eslabones está limitado, que tiene una porción proximal (2p) dotada de un lazo (3) configurado para rodear el vaso sanguíneo con el propósito de comprimirlo y una porción distal (2d) configurada para cerrar el lazo (3) mediante la aplicación de tracción;  - a chain (2) formed by links where the maximum angle of rotation between each pair of links is limited, which has a proximal portion (2p) provided with a loop (3) configured to surround the blood vessel for the purpose of compressing it and a distal portion (2d) configured to close the loop (3) by tensile application;
- una caja (8) de almacenamiento conectable a un extremo distal (4d) del conducto (4) para el almacenamiento de una porción distal (2d) de la cadena (2), donde la caja (8) de almacenamiento comprende un saliente (10) esencialmente cilindrico que sobresale de un orificio de entrada de la misma y que está configurado para acoplarse al extremo distal (4d) del conducto (4); y  - a storage box (8) connectable to a distal end (4d) of the conduit (4) for the storage of a distal portion (2d) of the chain (2), where the storage box (8) comprises a projection ( 10) essentially cylindrical protruding from an inlet opening thereof and which is configured to engage the distal end (4d) of the conduit (4); Y
- un pasador (5) solidario al extremo proximal (4p) del conducto (4) configurado para formar el lazo (3) de la cadena (2), - a pin (5) integral with the proximal end (4p) of the configured conduit (4) to form the loop (3) of the chain (2),
- de modo que la cadena (2) puede recorrer el conducto (4) desde su extremo distal (4d) hasta su extremo proximal (4p) y sobresalir por su extremo proximal (4p) de modo que forma el lazo (3) configurado para rodear el vaso sanguíneo.  - so that the chain (2) can travel the conduit (4) from its distal end (4d) to its proximal end (4p) and protrude through its proximal end (4p) so that it forms the loop (3) configured to Surround the blood vessel.
PCT/ES2017/070031 2016-01-20 2017-01-19 Device for controlling the flow of blood in a blood vessel WO2017125636A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ES201630066A ES2630732B1 (en) 2016-01-20 2016-01-20 Blood flow control device in a blood vessel
ESP201630066 2016-01-20

Publications (1)

Publication Number Publication Date
WO2017125636A1 true WO2017125636A1 (en) 2017-07-27

Family

ID=59361504

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/ES2017/070031 WO2017125636A1 (en) 2016-01-20 2017-01-19 Device for controlling the flow of blood in a blood vessel

Country Status (2)

Country Link
ES (1) ES2630732B1 (en)
WO (1) WO2017125636A1 (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1607996A (en) * 1925-07-02 1926-11-23 Herbert J W Morgenthaler Surgical tourniquet
US3730186A (en) * 1971-03-05 1973-05-01 Univ California Adjustable implantable artery-constricting device
US4069825A (en) * 1976-01-28 1978-01-24 Taichiro Akiyama Surgical thread and cutting apparatus for the same
US20080097497A1 (en) * 2005-11-22 2008-04-24 Assad Samy R Pulmonary artery banding device
US20100191254A1 (en) * 2009-01-23 2010-07-29 Genesee Biomedical, Inc. Band Forming Apparatus
EP2554139A1 (en) * 2011-08-05 2013-02-06 Centre Hospitalier Universitaire Vaudois Actuating device for a surgical implant
WO2013018133A1 (en) * 2011-08-02 2013-02-07 J.Morita Manufacturing Corporation Pulmonary artery band
US20140236211A1 (en) * 2013-02-18 2014-08-21 King Abdullah International Medical Research Center Minimally invasive pulmonary artery band
MX2014011371A (en) * 2012-03-26 2015-05-28 Medical Innovation Dev Adjustable vascular ring, means for treating sfs syndrome and implantable kit including said ring, mold and method for obtaining such ring.

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1607996A (en) * 1925-07-02 1926-11-23 Herbert J W Morgenthaler Surgical tourniquet
US3730186A (en) * 1971-03-05 1973-05-01 Univ California Adjustable implantable artery-constricting device
US4069825A (en) * 1976-01-28 1978-01-24 Taichiro Akiyama Surgical thread and cutting apparatus for the same
US20080097497A1 (en) * 2005-11-22 2008-04-24 Assad Samy R Pulmonary artery banding device
US20100191254A1 (en) * 2009-01-23 2010-07-29 Genesee Biomedical, Inc. Band Forming Apparatus
WO2013018133A1 (en) * 2011-08-02 2013-02-07 J.Morita Manufacturing Corporation Pulmonary artery band
EP2554139A1 (en) * 2011-08-05 2013-02-06 Centre Hospitalier Universitaire Vaudois Actuating device for a surgical implant
MX2014011371A (en) * 2012-03-26 2015-05-28 Medical Innovation Dev Adjustable vascular ring, means for treating sfs syndrome and implantable kit including said ring, mold and method for obtaining such ring.
US20140236211A1 (en) * 2013-02-18 2014-08-21 King Abdullah International Medical Research Center Minimally invasive pulmonary artery band

Also Published As

Publication number Publication date
ES2630732B1 (en) 2018-05-30
ES2630732A1 (en) 2017-08-23

Similar Documents

Publication Publication Date Title
JP6761120B2 (en) Valve fastener
ES2306034T3 (en) ADJUSTABLE BAND WITH IMPROVED FLUID.
ES2349952T3 (en) IMPLANTABLE DEVICES FOR CONTROLLING THE INTERNAL CIRCUMFERENCE OF AN ANATOMICAL ORIFICE OR LUMEN.
ES2202757T3 (en) FABRIC STABILIZATION DEVICE FOR SURGERY USE.
ES2755938T3 (en) Prosthetic device for a heart valve
Daebritz et al. Experience with an adjustable pulmonary artery banding device in two cases: initial success-midterm failure
ES2315284T3 (en) MEMBER OF ALIGNMENT TO DELIVER A NON-SYNTHETIC DEVICE WITH A PRE-DEFINED ORIENTATION.
ES2232758T3 (en) GASTROPLASTIA RING.
ES2325406T3 (en) SURGICAL AND IMPLANTABLE ADJUSTABLE BANDS WITH A FLAT PROFILE AT THE TIME OF IMPLEMENTATION.
ES2213877T3 (en) SURGICAL DEVICE FOR FABRIC STABILIZATION WITH FEET OF REMOTE ACTION.
ES2277375T3 (en) FABRIC STABILIZATION DEVICE FOR USE DURING SURGICAL INTERVENTIONS.
ES2310609T3 (en) METHOD AND APPARATUS FOR THE EXTERNAL STABILIZATION OF THE HEART.
ES2202369T3 (en) APPARATUS TO REDUCE THE CIRCUMFERENCE OF VASCULAR STRUCTURE.
US20120203072A1 (en) Apical Instrument Port
ES2663646T3 (en) Surgical device
ES2289666T3 (en) PROCEDURE FOR MOUNTING AN ADJUSTABLE BAND.
BR112017013033B1 (en) STENT AND STENTS KIT FOR ADJUSTABLE INTERVENTIVE BLOOD FLOW REDUCTION
JP2002525161A (en) Device and method for reconstructing heart chamber geometry
RU2011114564A (en) GERD TREATMENT DEVICE
ES2289667T3 (en) BAND ADJUSTABLE FOR IMPROVED FLUID.
JPS63501926A (en) wound closure devices
KR102108233B1 (en) Adjustable vascular ring, means for treating sfs syndrome and implantable kit including said ring, mold and method for obtaining such ring
ES2574759B1 (en) DEVICE FOR THE TREATMENT OF COSTAL FRACTURES
Kohl et al. Operative techniques and strategies for minimally invasive fetoscopic fetal cardiac interventions in sheep
ES2663786T3 (en) Occlusion device of the left atrial appendage

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17741138

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17741138

Country of ref document: EP

Kind code of ref document: A1