IT201800004093A1 - VASCULAR DEVICE FOR VEIN SCLEROTHERAPY AND METHOD - Google Patents

Description

DESCRIPTION

The present invention generally relates to intravenous sclerotherapy devices in general. In particular, the present invention relates to a vascular device for the delivery of a sclerosing agent into a vein, in particular for the saphenous vein, and to a method of intravenous delivery of a sclerosing agent.

The varicose pathology of the lower limbs represents a very common pathology in the adult population, especially of the female sex.

The treatment of varicose disease makes use of numerous techniques, surgical or endovascular, to achieve the elimination of saphenous venous blood reflux in standing position. Among the known intervention techniques are stripping of the great saphenous vein, laser or radiofrequency thermal ablation, injection of sclerosing substances or injection of glues.

International guidelines increasingly provide for outpatient techniques (laser and radiofrequency) that present lower economic costs for the patient (sclerotherapy).

Sclerotherapy of the saphenous vein, in its most accredited technical evolutions, involves the injection, under ultrasound control, through an open tip catheter (introduced into the vein below the knee and positioned in the middle part of the saphenous tract of the thigh) of sclerosing substances , preferably in the form of sclerosing foam.

However, sclerosing therapy of the saphenous vein performed with this procedure is exposed to variable results in relation to various factors that affect the effect of the action of the sclerosing drug. In fact, the sclerosing effect is dependent on the quantity of sclerosing agent, the concentration of the sclerosing agent, the diameter of the vein, the contact time of the sclerosing agent with the vein wall and the dilution and inactivation action of the sclerosing agent from part of the blood component.

Furthermore, sclerosing therapy is negatively conditioned, especially if carried out at high doses, by the possibility that a high concentration of sclerosing agent generates effects of inflammation and prolonged pigmentation of the peri-saphenous tissue and of the skin in correspondence with the treated saphenous segment.

Furthermore, sclerosing therapy is negatively conditioned by the risk of thrombotic effects in venous districts at a distance from the treatment site (iliac veins, vena cava, pulmonary arteries), by the risk of spasm of the pulmonary venous districts, by allergy phenomena and by the risk that, in the case of patent cardiac foramen ovale (about 10% of the population), thrombotic and spastic phenomena may occur in the arterial sector, with ischemic symptoms in the brain and in other peripheral arterial districts.

The need for a vascular device for the release of a sclerosing agent in a vein and for a method of dispensing a sclerosing agent in a vein that allows to reduce the aforementioned risks and drawbacks related to known techniques is extremely felt.

In accordance with the invention, the above objects are achieved by a hemostasis device and a hemostasis method according to the attached independent claims. Preferred embodiments of the invention are defined in the dependent claims.

The characteristics and advantages of the vascular device and of the delivery method of a sclerosing agent will be evident from the description given below, given by way of non-limiting example, in accordance with the attached figures, in which:

Figure 1 shows a vascular device according to an embodiment of the present invention;

Figure 1A shows a cross section of a multi-lumen catheter of the vascular device according to an embodiment of the present invention;

- Figure 2 shows a sectional view of a vein in which a multi-lumen catheter of a vascular device is introduced according to an embodiment of the present invention, in a step of the method of delivery of the sclerosing agent;

- Figure 3 shows a sectional view of a vein in which a multi-lumen catheter of a vascular device is introduced according to an embodiment of the present invention, in a second step of the method of delivery of the sclerosing agent;

- Figure 4 shows a sectional view of a vein in which a multi-lumen catheter of a vascular device is introduced according to an embodiment of the present invention, in a third step of the method of delivery of the sclerosing agent;

- Figure 5 shows a sectional view of a vein into which a multi-lumen catheter of a vascular device is introduced according to an embodiment of the present invention, in a fourth step of the method of delivery of the sclerosing agent. In accordance with the attached figures, the reference numeral 1 generally indicates a vascular device 1 for delivering a sclerosing agent into a vein, preferably in the saphenous vein, of a human or animal subject.

In particular, therefore, the vascular device 1 is preferably intended for sclerotherapy of the saphenous vein.

The vascular device 1 comprises a multi-lumen catheter 10 comprising at least one internal lumen 11 for the infusion of the sclerosing agent, a closed distal end 12 and a proximal end 13.

The multi-lumen catheter 10 is preferably made of flexible plastic material, for example of polyurethane or silicone. Preferably, the multi-lumen catheter 10, and in particular, its outer casing 110 has an external diameter comprised between 2 and 3 mm, preferably 2.3 mm.

The vascular device 1 further comprises at least one proximal occlusion balloon 2 and one distal occlusion balloon 3. Each balloon 2, 3 is individually and separately inflatable through one or more accessory lumens 15, 16 of the multi-lumen catheter 10. Each balloon from occlusion 2, 3 is suitable for limiting or totally preventing the blood flow in the vein to create a treatment zone T for the release of the sclerosing agent.

Preferably, the occlusion balloons have a diameter of about 20 mm and an inflation volume comprised in a range of between about 2 and 4 ml, extremes included.

The multi-lumen catheter 10 in addition to the internal lumen 11 comprises one or more accessory lumens 15, 16, all enclosed within a single external envelope 110. In a preferred embodiment, the multi-lumen catheter 10 comprises two accessory lumens 15, 16 , in addition to the internal lumen 11.

Preferably, the inner lumen 11 has a larger diameter than the accessory lumens. For example, the inner lumen 11 has a diameter of 16 gauge, while the accessory lumens 15, 16 have a diameter of 18 gauge. In one example, the catheter 10 has a length of about 60cm. In particular, each accessory lumen 15, 16 is connected to a respective occlusion balloon 2, 3 to allow its inflation and deflation.

On the multi-lumen catheter 10 there is at least one opening 14 in the treatment zone T suitable for delivering the sclerosing agent.

The vascular device 1 further comprises a first pressure detection device 4, for example a manometer, suitable for detecting the internal pressure of the balloon from proximal occlusion 2 and a second pressure detection device 5 suitable for detecting the internal pressure of the balloon to be distal occlusion 3, so as to allow the occlusion pressure to be monitored to prevent a damaging overpressure of the venous wall.

Preferably, each manometer comprises an occlusion pressure indicating element suitable for signaling at least a pressure range comprised between 20 and 30mmHg.

Furthermore, the multi-lumen catheter is preferably impregnated with barium or tungsten salts so as to make it eco-reflective and allow adequate positioning within the subject's body by means of an echo scan.

In an embodiment, for example shown in Figure 1, the vascular device 1 comprises a distal balloon inflation port 31, a proximal balloon inflation port 21 and an inlet port 17 for the sclerosing agent, the latter in fluid communication with the opening 14 for the delivery of the sclerosing agent in the treatment zone T. Preferably, the inflation port of the distal balloon 31, the inflation port of the proximal balloon 21 and the inlet port 17 for the sclerosing agents are fluidically connected with the proximal end 13 of the multi-lumen catheter, each by means of a respective connecting duct, so as to be each connected to a respective lumen of the multi-lumen catheter 10.

Preferably, the proximal occlusion balloon 2 and the distal occlusion balloon 3 are spaced apart so as to define a treatment zone T comprised between 30 and 50cm, preferably of about 40cm. According to an embodiment according to the invention, on the multi-lumen catheter 10, in the treatment area T, a plurality of openings 14, 14 ', 14' 'having variable dimensions between 0.3 and 0, are made. 6 mm in diameter, where the diameter of the most proximal openings is less than the diameter of the most distal openings. This allows to obtain a distribution of the sclerosing agent in the entire treatment area in a more homogeneous way and and at the same time favors a diffusion of substances of various density and viscosity, within the venous segment between the two balloons, during the phase of injection.

In particular, the openings 14, 14 ', 14' 'are made on the internal lumen 11 along most of the length of the multi-lumen catheter 10 (preferably on about 2/3 of the length of the catheter, for example about 40 cm. ), in the segment placed between the distal occlusion balloon 3, preferably positioned 2 cm from the tip of the catheter, and the proximal one, preferably positioned 18 cm from the proximal end 13.

In an advantageous embodiment of the invention, the vascular device 1 comprises a guide 6, for example a guide wire, at least partially made of an electrically conductive material (for example metal), which can be inserted into the internal lumen 11 and adapted to be operatively connected with an electrical unit 7 configured to generate electrical pulses. In the aforementioned embodiment variant, the vascular device 1 comprises an accessory opening 18 suitable to be crossed by a guide end 61 of the guide 6 to allow the guide 6 to come out of the internal lumen 11 towards the treatment area T in the vein.

Preferably, the guide end 61, once outside the catheter, assumes an arched shape, preferably an inverted or oblique J shape, so as to favor contact with the vein wall and transmit the electrical stimulus effective for obtaining the spasm of the vein.

In a preferred embodiment, the guide 6 is a metal guide wire for vascular intervention with the function of an electrode, to be used in the retraction phase of the catheter, at the end of the aspiration of the sclerosing product in the form of residual foam. Preferably, this metal guide wire has a length of about 57 cm. The guide 6, once completely inserted into the internal lumen 11, protrudes about 2 cm from the accessory opening 18 placed laterally on the lateral catheter 10, preferably at about 5 cm. from the distal end 12 of the catheter and about 1 cm below the distal occlusion balloon 3.

Preferably, the electrical unit 7 is configured to generate non-direct current electrical pulses, for example alternating or intermittently continuous. Preferably, the electrical unit 7 comprises a button that can be activated by the operator to generate the electrical stimulation impulses.

For example, the electrical pulse has a duration between 0.5 ms and 2 ms, preferably about 1 ms and an amplitude between 2 and 5V, preferably 3V.

In a variant embodiment, the electrical pulse has a frequency between 30 and 80 Hz and a pulse duration between 100μs and 300μs, preferably 200μs.

The present invention also relates to a method for delivering a sclerosing agent into a vein, preferably the saphenous vein, of a human or animal subject. Preferably, the method is performed by using a vascular device according to the present invention, described in the previous paragraphs of this discussion.

The method comprising the steps of:

to. insert a multi-lumen catheter 10 into the vein, preferably the saphenous vein, wherein said multi-lumen catheter 10 comprises at least one internal lumen 11 for the infusion of the sclerosing agent, a closed distal end 12, a proximal end 13, at least one proximal occlusion balloon 2 and one distal occlusion balloon 3;

b. inflating the distal occlusion balloon 2 to substantially limit or block the main venous return;

c. washing the lumen of the vein by delivering saline solution through the internal lumen 11 and the leakage of this saline solution from at least one opening 14 obtained on the catheter, to expel the blood;

d. inflating the proximal balloon 3 to avoid the wasteful filling of the venous segment by the residual blood in the terminal vein portion;

And. aspirate the residual saline solution into the vein;

f. deliver a sclerosing agent through the internal lumen 11 and the opening 14, in the treatment area T of the vein defined between the two inflated balloons; g. wait sufficient time for the action of the sclerosing agent.

Furthermore, preferably, the method includes the steps of - aspirating the sclerosing agent from the outside, through the internal lumen 11;

- possibly deflate the two occluding balloons;

- inserting a guide 6 at least partially made of an electric current conducting material, until one of its ends 61 comes out in the treatment area T of the vein and until it comes into contact with the walls of the vein;

- activating an electric unit 7 to conduct electrical impulses on the guide 6 suitable for obtaining spasm of the smooth muscle of the vein wall, preferably during the step of unthreading the catheter from the vein.

An even more detailed example of the entire sclerosing vein treatment procedure is better understood with reference to Figures 2 to 5. Below we will refer in particular to the saphenous vein, but the method can be generalized to other types of venous vessels.

The multi-lumen catheter 10 is introduced, preferably by means of a suitable introducer, with an adequate metal support guide, into the saphenous vein below the knee.

The distal end 12 of the catheter 10 is positioned, by means of an ultrasound survey of the position, at the level of the saphenous-femoral ostium.

The distal occlusive balloon 3 is inflated, as shown in figure 2, at a suitable pressure (indicated by a pressure gauge, to avoid overpressure and damage to the vein), to block the main venous return in the saphenous vein.

Subsequently, the saphenous lumen is washed with saline, in order to expel the blood, through the internal lumen 11, with outflow from the openings 14, 14 ', 14'.

In a subsequent phase (figure 3), the proximal occlusion balloon 2 is inflated at a suitable pressure (indicated by a pressure gauge, to avoid overpressure and damage to the vein), in order to avoid the wasteful filling of the saphenous segment by the blood in the terminal saphenous.

Through the internal lumen 11, the residual saline solution in the saphenous is aspirated, and the sclerosing agent is introduced, which fills the saphenous lumen between the two inflated balloons (treatment area T), without escaping from the saphenous lumen .

Once the necessary time (5-10 min.) For the action of the sclerosing agent has been waited, the sclerosing agent is aspirated towards the outside, through the openings 14, 14 ', 14' 'of the lumen internal 11. This allows to obtain a reduction effect of allergic, spastic and thrombotic complications at a distance.

At the conclusion of the procedure:

to. the balloons are deflated from occlusion (figures 4 and 5),

b. the guide 6 is introduced, connected to the power supply device, until the end 61 comes out and comes into contact with the walls of the saphenous vein;

c. the electrical unit 7 is activated to provide electrical impulses suitable for obtaining spasm of the smooth muscle of the saphenous vein wall during the removal phase of the device (catheter guide wire electrode).

The stimulation of the saphenous vein wall in order to obtain spasm of the same is carried out until the extraction of most of the catheter (40-50 cm. Approximately), for example signaled by a special marker or change in the color of the catheter in its 10 cm . terminals.

Subsequently, the multi-lumen catheter 10, the introducer system and the guide 6 are completely removed. At the conclusion of the procedure, a dressing is applied to the skin entry hole, and an elastic compression of the limb with a therapeutic stocking is performed, for example of the K1-2 single tights type.

Innovatively, the present invention allows to obtain an injection of sclerosing agent in a saphenous segment as bloodless as possible, and with a reduced risk of acting with dangerous overpressures on the walls of the vein by the occlusion balloons. In fact, the presence of pressure detection devices allows the pressure acting on the vessel walls to be constantly and independently monitored.

Advantageously, thanks to the bloodless lumen, the sclerosing agent can be used at reduced concentrations to avoid irritating complications of the peri-saphenous tissues (nervous and skin).

Furthermore, the sclerosing agent can remain in contact with the vein wall for a period of time adequate to obtain its action, without undergoing dilution and inactivation by the elements of the blood.

Furthermore, advantageously, the sclerosing agent can be aspirated, through the same internal lumen operated for the infusion, after an adequate contact time with the saphenous wall (5-10 min.), In the final phase of the procedure, in in order to avoid its entry into the deep venous circulation up to the pulmonary circulation. This significantly reduces the risks of allergy, vascular spasm and distant thrombosis.

Furthermore, advantageously, the electrical stimulation of the vein wall in order to obtain spasm of the same allows to increase the effectiveness of the sclerosing treatment.

It is clear that a person skilled in the art, in order to meet contingent and specific needs, may make changes to the invention described above, all however contained within the scope of protection as defined by the following claims.

Claims (14)

CLAIMS 1. Vascular device (1) for the delivery of a sclerosing agent into a vein, preferably in the saphenous vein, of a human or animal subject, comprising: - a multi-lumen catheter (10) comprising at least one internal lumen (11) for the infusion of the sclerosing agent, a closed distal end (12) and a proximal end (13); - at least one proximal occlusion balloon (2) and one distal occlusion balloon (3), each balloon (2, 3) being separately inflatable through one or more accessory lumens (15, 16) of the multi-lumen catheter (10) and being adapted to restrict or totally prevent blood flow in the vein to create a treatment zone (T) for the release of the sclerosing agent; - at least one opening (14) made on the catheter in the treatment zone (T) suitable for the delivery of the sclerosing agent; - a first pressure detection device (4), for example a manometer, suitable for detecting the internal pressure of the balloon from proximal occlusion (2) and a second pressure detection device (5) suitable for detecting the internal pressure of the balloon from distal occlusion (3), so as to allow the monitoring of the occlusion pressure to prevent a damaging overpressure of the venous wall. Device (1) according to claim 1, wherein each manometer comprises an occlusion pressure indicating element suitable for signaling at least a pressure range comprised between 20 and 30mmHg. Device (1) according to claim 1 or 2 wherein the multi-lumen catheter is impregnated with barium or tungsten salts so as to make it eco-reflective. Device (1) according to any one of the preceding claims, comprising a distal balloon inflation port (31), a proximal balloon inflation port (21) and an inlet port (17) for the sclerosing agent in communication fluidics with the at least one opening (14) for dispensing the sclerosing agent into the treatment zone (T). 5. Device (1) according to any one of the preceding claims, in which the proximal occlusion balloon (2) and the distal occlusion balloon (3) are spaced apart so as to define a treatment zone (T) between 30 and 50cm, preferably about 40cm. Device (1) according to any one of the preceding claims, in which a plurality of openings (14, 14 ', 14' ') having variable dimensions between 0.3 and 0 are made on the catheter in the treatment area (T) , 6 mm in diameter, where the diameter of the most proximal openings is less than the diameter of the most distal openings. Device (1) according to any one of the preceding claims, comprising a guide (6), at least partially made of electrically conductive material, which can be inserted into the inner lumen (11) and adapted to be operatively connected to a suitable electrical unit (7) to generate electrical impulses. 8. Device (1) according to claim 7, comprising an accessory opening (18) suitable to be crossed by a guide end (61) to allow the guide (6) to exit from the inner lumen (11) towards the area treatment (T) in the vein. Device (1) according to claim 8, wherein the guide end (61), once outside the catheter, assumes an arcuate shape, preferably an inverted or oblique J shape, so as to favor contact with the wall of the vein and transmit the effective electrical stimulus to obtain the spasm of the vein. 10. Device (1) according to claim 7, 8 or 9, in which the electrical unit is configured to generate non-direct current electrical pulses, for example alternating or intermittently continuous. 11. Device (1) according to claim 10, in which the electrical pulse has a duration between 0.5 ms and 2 ms, preferably about 1 ms and an amplitude between 2 and 5V, preferably 3V. 12. Device (1) according to claim 10, in which the electrical pulse has a frequency between 30 and 80 Hz and a pulse duration between 100μs and 300μs, preferably 200μs. 13. Method of delivering a sclerosing agent into a vein, preferably the saphenous vein, of a human or animal subject, comprising the steps of: to. insert a multi-lumen catheter (10) into the vein, wherein said multi-lumen catheter (10) comprises at least one internal lumen (11) for infusing the sclerosing agent, a closed distal end (12), a proximal end (13), at least one proximal occlusion balloon (2) and one distal occlusion balloon (3); b. inflate the distal occlusion balloon (2) to substantially limit or block primary venous return; c. wash the lumen of the vein by delivering saline solution through the internal lumen (11) and coming out of at least one opening (14) made on the catheter, to expel the blood; d. inflating the proximal balloon (3) to avoid the wasteful filling of the venous segment by the residual blood in the terminal vein portion; And. aspirate the residual saline solution into the vein; f. deliver a sclerosing agent through the internal lumen (11) and the opening (14), in the treatment area (T) of the vein defined between the two inflated balloons; g. wait sufficient time for the action of the sclerosing agent. The method according to claim 13, further comprising the step of: - aspirate the sclerosing agent from the outside, through the internal lumen (11); - possibly deflate the two occluding balloons; - insert a guide (6) at least partially in electric current conducting material, until one end (61) comes out in the treatment area (T) of the vein and until it comes into contact with the