JPS61141357A - Artificial three-lobe valve - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to an artificial trileaflet valve used in the circulatory system of a living body, an artificial heart, and the like.

[Conventional technology] The five conventional artificial trilobate valves include bioprosthetic valves that are formed into a shape similar to bioprosthetic valves by processing and disinfecting the valves and tissues of pigs and cows, and those made of rigid materials such as alloys and pyrolytic carbon. There were two types of mechanical valves, which had flat valve leaflets made of a material with a high temperature and were supported by bearings or a support frame.

However, the former method has the problem of calcium deposits occurring on the surface of the valve leaflets and lacks durability.The latter method has been attempted to prevent patients from continuing to take anticoagulants, but it is not durable. However, there was a problem in that the open resistance was large.

[Problems to be Solved by the Invention] The present inventors have discovered that the above-mentioned problems that occur in artificial trilobular valves using synthetic polymer materials can be solved by changing the curved surfaces of the valve leaflets to spherical or ellipsoidal surfaces similar to those of biological valves. It was confirmed that this is because the valve leaflet undergoes in-plane deformation in addition to out-of-plane deformation when the valve opens and closes due to the compound curved surface of the valve, and based on this knowledge, the present invention was made. It is something that

That is, the present invention reduces the opening resistance of the valve by making the main part of the leaflet of the artificial trileaflet valve into a single part so that only out-of-plane deformation occurs in the leaflet when the valve is opened and closed. At the same time, it significantly reduces the strain and deformation that occurs on the valve leaflets when the valve opens and closes, and improves the durability of the valve leaflets. The three valve leaflets provided between the strut parts are formed by a single part that is inclined with respect to the axis of the outer frame and movable symmetrically with respect to a plane that intersects each other at approximately equal angles, and the single part The above-mentioned problem was solved by providing a connecting edge that connects with a very small width when the valve is closed, on the leading edge of the valve.

[Function 1] In the artificial three-leaflet valve having the above configuration, the valve leaflets connected between the outer frame and its struts are made of a flexible synthetic polymer material, so when blood, etc. is pumped out, the inlet During operation of the artificial trileaflet valve, pressure from the direction causes the leaflets to deform outwardly, thereby ejecting from the central opening formed.
Since the main part of the valve leaflet is formed from a single part, only one out-of-plane deformation occurs and no in-plane deformation occurs, so that the opening resistance of the valve can be sufficiently reduced and the durability can be improved. 1 [Example] FIGS. 1(a) and 1(b) show the basic shape of the artificial trilobular valve of the present invention, in which three valves are arranged between the support portions 18 in the hollow annular outer frame 1. Two cusps are installed in succession. These valve leaflets 2 are formed by a single part that is inclined with respect to the axis of the outer frame 1 and movable symmetrically with respect to a plane that intersects each other at approximately equal angles, as shown in FIG. 1(b). ), one of the planes is indicated by a straight line AB. Therefore, it will be displaced in the first place.

The above-mentioned valve leaflet 2 consisting of a single part becomes a part of a conical surface or an elliptical cylindrical surface connected to the strut part 1a of the outer frame 1 in the above-mentioned plane, but if it is a single part, It is not necessarily limited to a conical surface or an elliptical cylindrical surface, but may be any surface that can be expanded to become a flat surface.

The distal edge 2a of the valve leaflet 2 having the above-mentioned basic shape is an arbitrary curved line (the distal edge 2a is not shown accurately in FIGS. 1(a) and 1(b) for the sake of simplicity). 2 is in the molded state, as shown in FIG. 1(a), the tip edge 2a
A space 3 is formed without joining each other, and each leaflet is formed in a half-open state. When the outflow of blood stops due to the pulsation of the heart, the valve leaflets 2 are deformed inwardly by the pressure applied to the valve leaflets 2 from the exit direction, so that the space 3 is deformed together with the deformation of the struts. , the distal edges 2a of the valve leaflets 2 are mutually connected, but since the closure of the valve is incomplete only by joining the distal edges 2a of the valve leaflets 2 to each other, the distal edges 2a of the single portion forming the valve leaflet are closed. It has a continuous joining edge that joins with a very small width at the time of the valve.

To explain the present invention in detail with reference to FIG. 2, between the pillars 11a of the hollow annular outer frame 11 made of a flexible synthetic polymer material with excellent biocompatibility, similar to the valve leaflets 2 described above, Three valve leaflets 12 are connected to each other. These leaflets 12
is formed by a single curved surface that is inclined with respect to the axis of the outer frame 11 and moves symmetrically with respect to a plane that intersects each other at approximately equal angles, and the tip edge 12a thereof has a
As illustrated in Figure 3, when the valve is closed, the valve leaflets join each other within a very small width, and at the same time, the leaflets themselves are made of a flexible material, so there is no particular resistance to the opening and closing of the leaflets. .

In the trileaflet valve having the above-mentioned valve leaflets 12, when blood flows upward in the outer frame 11 in FIG. 2 due to heart pulsation,
When the center line of the valve leaflet 12 deforms to the D2B position, the valve is opened and blood flows, and the blood flow stops and regurgitation occurs, the valve leaflet 12 moves inward due to the pressure applied from the exit direction, and the valve leaflet 12 moves inward to the B position. In combination with the fact that the outer shell 11 is made of a flexible material, the joining edges 13 join together, so that the valve is completely closed.

The strength of the artificial three-leaflet valve can be improved by using a composite material in which a synthetic polymer material with excellent biocompatibility is reinforced with a material having high strength.

By making the main parts of the three leaflets into single curved surfaces,
When the leaflets open and close, only out-of-plane deformation occurs in the leaflets;
Since in-plane deformation does not occur, the opening resistance of the valve is reduced, and the strain and deformation that occurs when opening and closing the valve leaflets is significantly reduced, so that the durability of the trileaflet valve can be improved.

In addition, since a very small joining edge is formed at the tip of the valve leaflet,
Although the main part of the valve leaflet has a single curved surface to improve durability, it does not cause incomplete closure due to the tip of the leaflet shifting, and the tips of the leaflets are completely joined to form a three-lobed structure. The valve can be sealed.

[Brief explanation of drawings]

FIG. 1(a) is a plan view showing the basic shape of the trilobal valve of the present invention, FIG. 1(b) is a side view of the same, FIG. 2 is a side view showing an embodiment of the present invention, and FIG. FIG. 2 is an explanatory perspective view of a valve leaflet in the present invention. 11... Outer frame, lla... Support section, 12...
Fist valve leaflet, 12a-Φ・tip edge, 13...joint edge. Designated representative: Director of Product Science Research Institute, Agency of Industrial Science and Technology, Shoji Takahashi Figure 312. figure

Claims (1)

[Claims] 1. In a three-leaflet valve used in biological and artificial circulatory systems, three leaflets are provided between the struts of a hollow annular outer frame made of a flexible synthetic polymer material with excellent biocompatibility. It is formed by a single curved surface that is inclined with respect to the axis of the outer frame and moves symmetrically with respect to a plane that intersects each other at approximately equal angles, and is joined to the tip edge of the single curved surface with a minute width when the valve is closed. An artificial three-lobed valve characterized by continuous joining edges.