EA031620B1 - Device for removal of blood vessel obstruction - Google Patents

Abstract

The device relates to articles of medical equipment, and more particularly to devices for removal of blood vessel obstruction. The task of the invention is to enhance the efficiency of intravascular mass destruction and also to improve convenience of use. The set task is solved by suggesting a device for removal of blood vessel obstruction containing an ultrasonic oscillation generator, an ultrasonic transducer and a connected with it concentrator-waveguide connected with a liquid supply or aspiration line and made in the form of a stepped cylindrical tube with an internal hole with an olive-shaped working head formed on the distal end.

Description

The invention relates to medical equipment, namely, devices for eliminating obstruction of blood vessels.

A device for intravascular removal of athereblashes is known, consisting of a catheter with an ultrasound transfer unit located in the inner part of the catheter, and directly connected to an ultrasound-generating device with a frequency of 22 kilohertz (kHz). The node is a spherical head enlarged from the distal side, which can be extended from the distal side of the catheter. The head can be provided with a neck or a radial groove and a cutting edge (European patent application No. EP 0835644 A2).

A device for intravascular thrombectomy of thrombus and thromboembolus is known, which contains a catheter-waveguide, which is connected to an ultrasonic transducer, and a working head located in the distal part of the catheter-waveguide, characterized in that the working head is made in the form of two hemispherical parts facing each other concave surfaces fixed coaxially on the catheter-waveguide, while the lower hemispherical part of the working head has through holes parallel to the catheter-waveguide, and is located on distance from the upper hemispherical portion equal to λ / 8π, where λ - length of the ultrasonic wave supplied to the catheter waveguide, n = 1, 3 or 5 (patent of the Republic of Belarus for the invention № 5759).

A device (waveguide) for intravascular thrombectomy of thrombi and thromboembolus is known, consisting of a metal cylindrical rod of variable cross section and a working head located at the end of the distal stem, differing in that the length of the proximal stem is from 2 to 4λ, where λ is the length of the longitudinal ultrasound oscillations of the waveguide itself, and the length of the middle and proximal parts is at least 1 / 2λ, and the transitions between the proximal, middle and distal parts of the waveguide are in the form of a hub Fu When the ratio of cross-sectional areas is no more than 1.5: 1, and the conical transitions are made in the places of the antinodes of the longitudinal oscillations of the waveguide itself, the diameter of the working head is 1.5 times the diameter of the distal part (Eurasian patent number 005704).

This device is a prototype in relation to the claimed device. Common features for the claimed device and the prototype are that the concentrator-waveguide of the claimed device and the prototype consist of a metal cylindrical rod and a working head located at the end of the distal part of the rod.

A disadvantage of the known devices is that their design does not allow for the complete destruction of the intravascular formations and for the continuous supply and aspiration of fluid during the treatment of the affected area.

The task of the invention is to increase the efficiency of destruction of intravascular structures. The claimed invention is also aimed at improving the reliability of the device and improving safety when performing the procedure for eliminating obstruction of blood vessels, as well as improving convenience during operation.

The problem is solved by the fact that the proposed device for eliminating obstruction of blood vessels, consisting of an ultrasonic oscillation generator, an ultrasonic transducer and a concentrator-waveguide (Fig. 1), made in the form of a cylindrical tube 1 of a stepped shape with a smooth transition from the proximal part of a large diameter to distal parts of a smaller diameter, at the end of which a working head is formed in the form of an olive, equipped with holes and equipped with a latch (connector), providing direct and reverse current through the first fluid inside the cavity, as well as node connection to the ultrasonic transducer, comprising a planar screw 2 and washer 3.

The waveguide hub consists of a working part and a mount.

The working part of the concentrator-waveguide is made in the form of a cylindrical tube of a stepped form with a smooth transition from the proximal part of a large diameter to the distal part of a smaller diameter, at the end of which an operating head in the form of an olive is formed, having a central hole that is a continuation of the hole of the proximal and distal waveguide. The working head has at least three holes, equidistant from each other and made in the plane perpendicular to the axis of the central hole at the maximum diameter of the working head. These openings are intended for the impact of the cavitation jet on the intravascular formations and for the ultrasound remodeling of the vascular wall.

The hub-waveguide attachment unit is made in the form of a cylindrical tube and includes a latch (connector) for connecting the fluid supply or aspiration line and the hub-waveguide attachment unit to the ultrasonic transducer, including a screw and a flat washer.

To ensure the reliability and safety of operation of the device, the working head of the concentrator waveguide can be performed (configured) without using connecting operations, for example, by the method of plastic deformation. The implementation of the concentrator-waveguide without the use of connecting operations allows you to avoid destruction (detachment) of the working head in the form of olive due to mechanical vibrations.

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To ensure ease of operation of the invention, the concentrator-waveguide can be made with a bend in the area of the attachment point between the retainer (connector) for connecting the liquid supply or aspiration line and the attachment point for the concentrator-waveguide to the ultrasonic transducer at an angle of at least 30 °.

Also, to ensure ease of operation, the node connecting the concentrator-waveguide to the ultrasonic transducer (Fig. 2) includes a screw 2 and a flat washer 3 with a thickness of 0.5-5 mm, with λ η - attached to a cylindrical tube 1 of a stepped shape at a distance of 4 from the proximal end of the concentrator - waveguide, where n is an integer from the series 1, 3, 5, 7, ..., λ is the wavelength of longitudinal oscillations λ η— in the material of the concentrator-waveguide, and at a distance of 2 from the distal end, where n is an integer from the series 1, 2, 3, 4, ..., λ is the wavelength of the longitudinal oscillations in the material waveguide concentrator. This design of the hub-waveguide attachment unit to the ultrasonic transducer provides the possibility of connection with the ultrasonic transducer without its rotation relative to the transducer itself.

For direct and reverse flow of fluid through the internal cavity of the concentrator waveguide, its attachment unit (proximal part) is provided with a latch (connector) providing connection to Male type Luer-Lok connectors, which are widely used when connecting products for infusion therapy.

The invention is characterized by the following drawings.

FIG. 1 shows a general view of the concentrator-waveguide, where 1 is a cylindrical tube of a stepped form, 2 is a screw, 3 is a flat washer, 4 is a clamp (connector) for connecting a fluid supply or suction line.

FIG. 2 - hub-waveguide attachment unit to the ultrasonic transducer, where 1 is a stepped cylindrical tube, 2 is a screw, 3 is a flat washer.

FIG. 3 - the working part of the waveguide concentrator in the context of the procedure for eliminating obstruction of blood vessels, where 1 is a stepped cylindrical tube, 5 is the working head in the form of an olive, 6 is the central hole, which is a continuation of the hole of the proximal and distal part of the waveguide concentrator, 7 - holes located perpendicular to the axis of the concentrator-waveguide, 8 - a catheter into which the concentrator-waveguide is placed.

The claimed invention operates as follows (Fig. 3). The waveguide concentrator is placed in the catheter 8. From the ultrasound transducer through the screw 2 and the flat washer 3, the mechanical vibrations of the ultrasonic frequency are transmitted to the distal part and to the working head 5. Due to the fact that the working head in the form of an olive has holes 6 and 7 connected to the cavity concentrator-waveguide, through which the flow of fluid, provides high security destruction of a blood clot, eliminates the likelihood of dissection of the vascular wall. The presence of holes located perpendicular to the axis of the Central hole 7, allows you to handle the walls of the vessel and increases the area of the thrombus. At the exit from the central hole 6 of the working head 5 of the concentrator-waveguide, a column-shaped cavitation jet is formed, which provides for the remote destruction of a thrombus or thrombo-embolus at some distance from the working head.

When the device is working, the working head 5 with holes 6 and 7 is removed from the catheter 8 with the condition that the distance from the end part of the catheter 8 to the near edge of the hole 7, perpendicular to the axis of the waveguide concentrator, does not exceed 0.5 mm. The flow of fluid in the treatment area during operation of the device through the cavity inside the concentrator-waveguide and the holes 6 and 7 in the working head. Aspiration of fluid and degradation products from the treatment area is carried out through the annular gap between the working head 5 and the walls of the catheter 8. If necessary, it is possible to provide a reverse flow of fluid: flow through the annular gap, aspiration through the holes 6 and 7 in the working head 5 and the cavity of the waveguide concentrator .

Example.

Patient B., 62 years old. Diagnosis: acute ischemia of the right lower limb, 48 hours old. Diagnostic angiography of the peripheral arteries showed occlusive thrombosis throughout the popliteal artery. According to the quantitative analysis, the length of thrombotic occlusion was 4 cm and a diameter of 0.5 cm. It is necessary to destroy the thrombus and achieve full restoration of the patency of the affected vessel. For this antegrade, in a standard way, the right common femoral artery was punctured and a catheter with a waveguide concentrator was introduced into the bloodstream through the introducer sheath. Then, under the angiographic control, the catheter was brought in with the concentrator-waveguide until it was in contact with the thrombus surface. The choice of the waveguide concentrator is due to the prescription of the formation of a blood clot in the vessel and its strong attachment to the atherosclerotic changed artery wall. Then, ultrasonic combined vibrations with a frequency of 22-36 kHz were applied to the concentrator-waveguide and the catheter with the concentrator-waveguide was advanced from the proximal to the distal end of the thrombus and back. At the same time, aspiration along the catheter channel of the products of destruction was performed.

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Thus, the proposed device in comparison with analogues allows to obtain the following advantages:

the device allows you to completely destroy blood clots, eliminate the likelihood of perforation of vessels and their injury from the action of large amplitudes of the working head;

the device allows you to prepare the area of the vessel for plastics and stenting, or to submit the necessary preparation to the treatment area;

the device allows remodeling of the vascular wall due to the impact of cavitation jets on it;

the device allows the destruction of blood clots due to cavitation processes, and due to mechanical destruction.

Information sources:

1. Application for European Patent No. EP 0835644 A2

2. The patent of the Republic of Belarus for invention No. 5759

3. Eurasian patent number 005704 (prototype)

Claims (2)

CLAIM 1. Device for eliminating obstruction of blood vessels, containing a generator of ultrasonic vibrations, an ultrasonic transducer and a hub-waveguide connected to it, connected to a fluid supply or aspiration line and made in the form of a cylindrical tube (1) of a stepped shape with an inner hole formed on the distal end a working head (5) in the form of olive, characterized in that the working head (5) contains at least three equally spaced holes (7) made in the plane, perp ikulyarnoy axis of the central hole (6) at the maximum diameter of the working head (5) and the fastening hub waveguide to the ultrasonic transducer is carried screw through a flat washer (3) attached to λ n - to the waveguide concentrator at a distance of 4 from the proximal end, where n is an integer from the series 1, 3, 5, Λ 7, ..., λ is the wavelength of longitudinal vibrations in the material of the hub-waveguide, and at a distance of 2 from the distal end, where n is an integer from the series 1, 2, 3, 4 ..., λ is the wavelength of longitudinal vibrations in the material of the waveguide concentrator, and the section between the retainer (4) for connecting the fluid supply or aspiration line and the connection unit of the waveguide concentrator to the ultrasonic transducer is made with a bend of at least 30 °. 2. The device according to claim 1, characterized in that the proximal part of the hub-waveguide is equipped with a latch that provides connection to the Luer-Lock connectors of type Male.