RU2477105C1 - Prosthesis of heart valve - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to field of medicine and can be applied in cardiac surgery in operations of natural heart valve replacement. Prosthesis includes ring-shaped case, limited by distal and proximal end surfaces, installed in case with possibility of turning for formation of passage section and its covering locking element, made in form of convex-concave leaves, and limiters of leaf motion in form of hook-shaped projections. On internal surface of hook-shaped projection made is flat region of hook-shaped projection, which interacts with leaf and limits it turning during opening.

EFFECT: increased reliability of leafs holding during movement, reduction of dander of thrombus formation and reduction of hydrodynamic resistance.

11 cl, 7 dwg

Description

Technical field

The invention relates to medicine, in particular to cardiovascular surgery, and is intended to replace affected natural heart valves during cardiac surgery.

State of the art

The most popular design of the prosthetic valve of the heart currently remains annular with repeated sashes inside the passage section. Such prostheses have high reliability and provide satisfactory hemodynamics, the corresponding improvements reduce acoustic noise, patient anxiety, increase the duration of smooth operation. Standard prostheses include an annular body. One or more valves are mounted in the body with the possibility of repetition between the open position for passing a direct blood flow and the closed position for blocking the channel and limiting the return blood flow. In addition, the prosthetic valve of the heart contains a connecting mechanism for connecting the valve body to the surrounding tissues of the heart. Basically, this mechanism is made in the form of a cuff, which is sewn to the tissues of the heart and covers the lateral surface of the valve prosthesis body. An important problem is the problem of reliable retention of the valves in the housing. For this, various types of hinges, travel and turn limiters are used. The prior art solutions that reduce the likelihood of valve failure due to poor fixation of the valves (see, for example, published US application No. 2007193632). In the prosthesis presented here, the flaps rotate on an axis fixed in the body and intersecting the bore in the center.

In the known device hemodynamics is significantly distorted due to the overlap of the center of the bore in the open position of the valve.

A number of designs are known (see US patent 4274437, RF patent 2066984) with the provision of the main zone of the flow area in the center. With this arrangement, it is obvious that the central part of the flow through the valve remains weakly perturbed, and the distortions introduced by the wings are minimal.

However, these valves are not used in surgical practice due to the low reliability and high likelihood of sash loss.

The closest analogue to the present invention is a heart valve prosthesis (RF patent 2370245), comprising an annular body limited by upper and lower ends, mounted in the body with the possibility of rotation to form a passage section and its overlap, a locking element made in the form of convex-concave valves and leaf stoppers, a rectangular groove is made in each leaflet, leaflet stoppers are made in the form of hook-shaped protrusions that have a rectangular cross section for mutual Procedure with through slots leaflets upon closing and opening, with the shutters stroke limiters are provided with stops to limit the rotation of the flaps.

However, in this valve, when the sash moves along the hook-shaped protrusion inside the protrusion, a dead zone forms, which can contribute to the formation of a thrombus, in addition, the hook-shaped protrusions with their back part extend beyond the perimeter of the body and directly adjoin the surrounding tissues of the heart, which can provoke the formation of a pannus from the connective tissues .

Disclosure of invention

The present invention is aimed at solving the problem of creating an artificial heart valve that eliminates the disadvantages of the known analogues, namely, providing high reliability and durability having a main stepless passage area in the center of the heart valve prosthesis. The technical result achieved by using the present invention is to increase the reliability of holding the valves during movement and to prevent contact of structural elements with the surrounding tissues of the heart, as well as to reduce hydrodynamic resistance. The technical result is achieved due to the fact that in the prosthesis of the heart valve, including an annular body limited by distal and proximal end surfaces, mounted in the body with the possibility of rotation to form a passage section and its overlap, the locking element is made in the form of convex-concave valves with a through rectangular a groove, and leaflet stoppers made in the form of hook-shaped protrusions that have a rectangular cross-section for interaction with through grooves st the cooler when they are closed and opened, while their inner surface consists of two cylindrical sections connected by a flat section, and on the long internal surfaces of the through rectangular groove two faces are made, and the shutters are made in the form of a conical section mated to a flat one, while at least the central part of the inner surface of the conical section is a continuation of the inner surface of the annular body, which is also made conical.

The technical effect is enhanced due to the fact that the rear side of the hook-shaped protrusions does not extend beyond the perimeter of the housing.

The case on the outside has an annular groove for attaching the sewing cuff, while it is possible to use a replaceable cuff. The body and wings are made of nanostructured pyrocarbon.

The list of drawings.

The invention will be better understood from the description below with reference to the position of the drawings, where Figures 1 and 2 show a prosthetic heart valve with closed flaps, respectively, a front view and a top view, Figures 3 and 4 show a prosthetic heart valve with open sashes, respectively, front view and top view, figure 5 shows a hook-shaped protrusion, figure 6 and 7 shows the sash, respectively, side view and top view.

Information confirming the possibility of carrying out the invention.

The heart valve prosthesis comprises an annular body 1 made of nanostructured pyrocarbon and having three convex-concave flaps 2, also made of nanostructured pyrocarbon and with the possibility of turning and forming the main passage area in the center, installed in the housing 1. The annular housing 1 is limited by the distal 3 and proximal 4 end surfaces. In each casement 2, a rectangular through groove 5 is made. The stroke limiters of the casements 2 are made in the form of three hook-shaped protrusions 6, which are rectangular in cross section and interact with the through grooves 5 of the respective casements 2 when they are opened and closed. The hook-shaped protrusions 6 are located on the proximal end surface 4 of the housing 1, and their inner surface consists of two cylindrical sections 7 and 8 connected by a flat section 9. The housing 1 has an annular groove 10 on the outside for fastening the sewing cuff, and the inner surface 11 is conical . The leaf 2 contains a conical section 12 and a flat section 13, and on the inner surface of the through groove 5 there are two faces 14. The arrows 15 and 16 indicate the forward and reverse blood flow, respectively.

The prosthesis of the heart valve works as follows. When the valve prosthesis is opened by direct blood flow, the leaflets 2 rotate, they are initially held securely by hook-shaped protrusions 6 interacting with the rectangular grooves 5 of each leaf 2. Rotation of the leaf 2 limits a flat section 9 made on the inner surface of the hook-shaped protrusion 6, interacting with the outer the surfaces of the wings 2. This rotation occurs to the position of the equilibrium state. In this case, the blood flows in the forward direction, the Central part of the opening of the valve body 1 passes freely without distortion. The flaps are located almost vertically and do not create resistance to flow. When the direct flow stops, the flaps 2 begin to rotate and return to their original position until they touch each other. The limited backflow of blood that occurs when the valve closes, washes the inner part of the hook-shaped protrusions 7 and part of the distal end surface 4.

The claimed design of an artificial heart valve has the following advantages:

1. Completely eliminates the loss of the sash due to the implementation of the limiters of the course of the sash hook-shaped protrusions.

2. Provides high efficiency of the valve cross section, practically without resistance to flow in the open position of the valves.

3. Eliminates the formation of stagnant zones by washing the areas of flow restrictors and stops with direct and reverse blood flow.

4. Significantly reduces the factor of thrombosis due to the exclusion of zones in the area of blood flow with high shear stresses.

5. Eliminates the instability of the valves in the open state due to the implementation of their outer surfaces convex-concave.

6. Reduces the risk of pannus development by eliminating contact of structural elements with surrounding heart tissues

7. Has high reliability, durability and good compatibility with natural fabrics.

Claims (11)

1. The prosthesis of the heart valve, including an annular body limited by the distal and proximal end surfaces, mounted in the body with the possibility of rotation to form a bore and its overlap, a locking element made in the form of convex-concave valves, and the course of the movement of the valves in the form of hook-shaped protrusions, characterized in that on the inner surface of the hook-shaped protrusion a flat portion of the hook-shaped protrusion is made, which interacts with the sash and limits its rotation when hiding. 2. The prosthesis according to claim 1, characterized in that the flat portion of the hook-shaped protrusion is limited to cylindrical sections, which together with the flat section provide the turning conditions of the fold. 3. The prosthesis according to claim 1, characterized in that the geometry of the sash portion in contact with the inner surface of the hook-shaped protrusion coincides with the geometry of the flat and cylindrical sections of the hook-shaped protrusion. 4. The prosthesis according to claim 1, characterized in that the rear side of the hook-shaped protrusions does not extend beyond the outer perimeter of the annular body. 5. The prosthesis according to claim 1 or 3, characterized in that the sash is made in the form of a conical section, paired with a flat section of the sash. 6. The prosthesis according to claim 1, characterized in that in the open position of the valve, at least the Central part of the inner surface of the conical section of the sash is a continuation of the inner surface of the annular body. 7. The prosthesis according to claim 1 or 4, characterized in that at the junction of the conical and flat sections of the sash, a through rectangular groove is made. 8. The prosthesis according to claim 6, characterized in that on the long internal surfaces of the through rectangular groove are made on two sides. 9. The prosthesis according to claim 1 or 3, characterized in that the inner surface of the annular body is conical. 10. The prosthesis according to claim 1, characterized in that the annular groove on the outside of the housing is also adapted for mounting a removable cuff. 11. The prosthesis according to claim 1, characterized in that the body and sash are made of nanostructured pyrocarbon.

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