SK286190B6 - Axially symmetric multi-leaflet valve substitution - Google Patents

Abstract

The valve substitution has in the inside of ring the groove (3) or hollow, where on the pin (5) are deposit leaf (4) amount four or six. The ring is made from the bottom part (1) and top part (2).

Description

Technical field

The invention relates to mechanical valve restorations, also called valve mechanical prostheses or artificial valves, which allow replacement of the natural heart valve in the event of its functional damage.

BACKGROUND OF THE INVENTION

In particular, two types of mechanical valve restorations are currently used:

- Disc flaps with centrally mounted flip disc.

Two-leaf (double-flap) with two leaves rotatable mounted on pins or axles, for example as described in US Patent 6,096075 and US 6,206918.

Said valves have been successfully implanted in many 10,000 applications and their reliability and durability is very good. However, they also have some drawbacks: their operation is associated, in particular with disc valves, with noise that the patient has to get used to; furthermore, there is an increased tendency to thrombus formation; not quite ideal character of flow profile and demanding production due to geometrical shapes of parts with required accuracy.

US Patent 6,395024 and US Patent Application disclose a three-leaf mechanical heart valve which consists of a housing comprising holes and equipped with a pin / hinge mechanism allowing the valve leaves to rotate and retain. The flap sheets are flat and have an overall S-shaped curvature on their outer surface. The flaps of this design have an improved flow rate over the double-leaf valves, since they provide free space for blood flow at their center where the blood flow is fastest. The disadvantage of said mechanical heart valves is their shape complexity, which makes their manufacture complicated.

SUMMARY OF THE INVENTION

The above-mentioned disadvantages are reduced by the multi-blade axially symmetrical mechanical valve replacement according to the invention, which is characterized in that in the rotary ring formed from the lower part and the upper part a groove is formed on the inner side. one whole. The ring may be single-piece or, in order to facilitate assembly, two-piece, preferably sewn together. For this purpose, there are holes between the lower part and the upper part of the flange ring, through which threads of synthetic material are threaded. If the ring is one-piece are used for assembly eg. elastic material deformation. This ring, which is made of a suitable metal, plastic or composite, has a sewn cuff made of synthetic textile. In the space above the groove, the ring has a continuous taper on the inside that serves as a stop for the leaves in the open position. Instead of a constriction, local protrusions may also be formed, in which case the ends of the pins must be housed in the wells in order not to rotate the leaf system about the axis of symmetry. The ends of the pins have the shape of a cone or part of a spherical or ellipsoidal surface and the like.

The sheets have a planar shape or, in order to improve the flow conditions, the shape of a portion of the surface of the cylinder. Made eg. of titanium alloy (sheet) or of carbon composite. After processing the straight sealing veneers, all the sheets of one flap are placed on the fixture and the arcuate sealing surfaces are machined at once.

In contrast to the prior art mechanical valve restorations for multi-leaf axially symmetrical valve restorations, according to the invention, the flow pattern is more similar to the flow in natural heart valves. Another advantage is that the weight and moment of inertia of the individual sheets are considerably lower, which both has a beneficial effect on the response rate and sensitivity, and also reduces the closing forces at closure, resulting in less noise and less damage to blood cells.

A noticeable advantage is also the axial symmetry of the valve restorations according to the invention, since the implanting surgeon is not burdened in the operation by seeking the optimal position (rotation) of the valve mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

In the figures, a particular embodiment of the multi-leaf axially symmetrical mechanical valve restorations according to the invention is shown. Figure 1 is a top view of the four-leaf valve replacement in the closed state and Figure 2 is in the open state. Fig. 3 shows the four-leaf valve replacement in section in the closed state and in Fig. 4 in the open state. In Figure 5 and Figure 6, the four-leaf valve replacement is in the closed and open state in a rotated section. Figure 7 shows the four-leaf valve replacement in a three-dimensional view in the closed state and Figure 8 in the open state. Figure 9 shows the five-leaf valve replacement in the closed state and Figure 10 in the open state. Figure 11 is a cross-sectional view of this valve replacement in the closed state and Figure 12 in the open state. Figure 13 shows the five-leaf valve replacement in a three-dimensional view in the closed state and Figure 14 in the open state. Fig. 15 shows the shape of the leaf of a four-leaf and Fig. 16 of the five-leaf valve replacement as well as a possible way of attaching the pins to the leaf.

DETAILED DESCRIPTION OF THE INVENTION

A particular embodiment of the invention shown in Figures 1 to 14 is a four-leaf and five-leaf axially symmetrical mechanical valve replacement with planar leaves. The basis of this embodiment is a two-part ring formed of a lower part 1 and an upper part 2, the parts of which have a centering position relative to each other and connected by means of flanges 7 with holes 8 after insertion of the leaf system 4 with pins 5 connected by a thread threaded through the holes 8. a groove 3 is formed in the lower part 1 and the upper part 2 and an axially symmetrical taper is formed above it, forming a stop 6 for the open position. The upper and lower part attributes are chosen to match the images. It will be understood that the flap restoration of the present invention may be used in a position other than that shown in the figures. On the leaves 4 are inserted pins 5, the ends of which are movably mounted in the groove 3. The method of connecting the pins 5 with the leaves 4 is apparent from Figures 15 and 16. In each of the identical leaves 4 there are two opposing recesses 11 in which the pins 5 notch 10, the width of which corresponds to the sheet thickness. The pins 5 in the case of a four-leaf valve replacement are terminated by a cone 12 with a 90 ° apex angle. The ends of the pins 5 in a five-leaf design are more complicated in shape due to the tightness. At the periphery of the ring 1,2 there is a sewn cuff 9 enabling sewing into the patient's annulus.

Industrial usability

Multi-leaf axially symmetrical mechanical valve restorations can be manufactured industrially by established technologies while respecting technical standards for inactive surgical implants. Production is less demanding, especially in the case of a four-leaf valve replacement with planar leaves and a ring of simply rotary shape.

Claims (9)

Multi-axially symmetrical mechanical valve restoration consisting of a ring and flap sheets, characterized in that a groove (3) or pivot holes (5) on which the flaps are attached are arranged inside the ring in a plane perpendicular to the axis of symmetry. (4) in the number of 4 to 6 and in the space above the groove (3) or the pegs (5), a stop for the open position of the flaps (4) is formed on the inside of the ring. A multi-leaf axially symmetrical mechanical valve restoration according to claim 1, characterized in that the ring is formed of a lower part (1) and an upper part (2) and the stop (6) for the open position of the flap sheets (4) is axially formed. -symmetrically reducing the diameter of the upper ring portion (2). A multi-leaf axially symmetrical mechanical valve restoration according to claim 1, characterized in that the stop (6) for the open position of the flaps (4) is formed by local projections located above the pits for receiving the pins (5). A multi-blade axially symmetrical mechanical valve restoration according to claim 1, 2 or 3, characterized in that the leaves (4) are curved in the form of a cylindrical surface, the axis of this surface being parallel to the axis of symmetry of the blade (4). A multi-leaf axially symmetrical mechanical valve restoration according to claim 1, 2, 3 or 4, characterized in that the flaps (4) and pins (5) are connected by means of corresponding grooves. A multi-leaf axially symmetrical mechanical valve restoration according to claim 1, 2, 3 or 4, characterized in that the flaps (4) and the pins (5) form a continuous integral unit. A multi-blade axially symmetrical mechanical valve restoration according to claim 1 or 2, characterized in that the groove (3) or pegs (5) are formed in the plane of the joint of the lower part (1) and the upper part (2) of the ring. A multi-blade axially symmetrical mechanical valve replacement according to any one of claims 2 to 7, characterized in that the lower part (1) and the upper part (2) of the ring are provided with flanges (7) with holes (8) for thread connection. A multi-blade axially symmetrical mechanical valve replacement according to any one of claims 2 to 7, characterized in that the lower part (1) or upper part (2) of the ring is externally provided with a sewn cuff (9) for sewing into the patient's annulus .