WO2003037226A1

WO2003037226A1 - Double-leaflet cardiac valvular prosthesis

Info

Publication number: WO2003037226A1
Application number: PCT/DE2002/003910
Authority: WO
Inventors: Rainer Frey
Original assignee: Rainer Frey
Priority date: 2001-10-23
Filing date: 2002-10-16
Publication date: 2003-05-08
Also published as: DE10151537A1

Abstract

The invention relates to a double-leaflet cardiac valvular prosthesis that comprises a substantially circular valve ring (1) with a ring opening (4), and a first and a second valve leaflet (2, 3). Said valve leaflets (2, 3) can be individually pivoted from a first position, in which the valve leaflets (2, 3) substantially obturate the ring opening (4), to a second position, in which the valve leaflets (2, 3) substantially release the ring opening (4). The valve leaflets (2, 3) engage with each other and are pivotally disposed on the valve ring (1) without a separate fastening pin.

Description

Double Wings heart valve prosthesis

The invention relates to a double-wing heart valve prosthesis with a substantially circular valve ring having a ring opening, a first and a second valve wing, the valve wings from a first position, in which the valve wings essentially close the ring opening, into a second position, in which the Flap wings essentially open the ring opening, can be pivoted independently of one another.

The heart of mammals comprises four valves (Valvae cordis), which are arranged on the heart skeleton, namely sail valves and pocket valves. The sail flaps (Valva atrioventricularis dextra and sinistra) are locking devices between atria and chambers. The crescent-shaped pocket flaps sit at the beginning of the pulmonary trunk and aorta.

The atrioventricular valves formed from endocardial folds and stiffened by sinewy fibrous plates close the way to the atria during contraction of the heart chambers (systole) in order to prevent the blood from flowing back. When the ventricles relax, the crescent-shaped pocket flaps in the pulmonary artery, the pulmonary valve, and in the aorta, the aortic valve, prevent the blood from flowing back into the chambers. The sail valves (atrioventricular valves) open and open the way for the blood in the atria.

If the heart is adversely affected by insufficiently closing heart valves, the defective heart valves can be exchanged for heart valve prostheses in a routine operation. For example, natural heart valves of humans are used for the exchange or animals such as pigs, cattle, etc. However, this can lead to immunological rejection reactions and / or infections of the recipient organism, for example with the HI virus (HIV). In this respect, transplants of biological heart valves are associated with an inevitable risk of rejection and / or infection.

In view of the above risks with natural heart valves, mechanical heart valve prostheses are increasingly being implanted.

A generic double-wing heart valve prosthesis is known from EP 0 650 705 A1. In the double-winged heart valve prosthesis known from EP 0 650 705 A1, two half-moon-shaped valve wings are arranged on a valve ring on a separate fastening axis. The crescent-shaped flap wings are articulated on the fastening axis. This separate mounting axis is eccentric, i.e. arranged parallel and at a distance to a circle diameter on the valve ring.

Although the double-wing heart valve prosthesis known from EP 0 650 705 A1 already has a relatively good usability, it nevertheless has some disadvantages. First, it is necessary that the two flap wings are articulated on an attachment axis. This requires a complex manufacturing process, since the holders provided on the valve ring must first be provided with aligned holes for the fastening axis. In a further step, the flap wings must be articulated on the fastening axis by the fastening axis being guided through sleeve sections provided on the flap wings. Then the fastening axis with the hinged flap wings can be arranged on the flap ring.

Furthermore, blood can penetrate and be retained in the sleeve sections after implantation of the heart valve prosthesis. Inadequate blood exchange can result in residues in the sleeve sections, for example due to dead erythrocytes, which promote the development of extremely dangerous blood clots. Hence, with regard to the Regular long-term use of such heart valve prostheses is a risk of thrombosis that should not be underestimated.

Furthermore, in the double-wing heart valve prosthesis known from EP 0 650 705 A1, the end sections of the fastening axis are regularly mounted in axle bearings. These axle bearings are arranged in or on the flap ring and regularly protrude far into the ring opening of the flap ring. This leads to an undesirable flow obstacle after implantation on the heart. This flow obstacle can on the one hand induce thrombus formation and on the other hand can lead to an undesirable change in the flow profile of the blood due to turbulence in the blood flow. Such a changed flow profile can lead, for example, to the formation of "dead water areas" in vessels, for example a cardiac ventricle, in which there is then no longer an adequate exchange of blood.

The object of the invention is therefore to provide a heart valve prosthesis that is simple to manufacture and is improved with regard to the aforementioned disadvantages.

The object on which the invention is based is achieved by providing a double-wing heart valve prosthesis with an essentially circular valve ring having a ring opening, a first and a second valve wing, the valve wings from a first position in which the valve wings essentially close the ring opening into one second position, in which the flap wings essentially open the ring opening, can be pivoted independently of one another, the flap wings being in engagement with one another and being pivotably arranged on the flap ring without a separate fastening axis. Preferred further developments are specified in the subclaims.

In the double-wing heart valve prosthesis according to the invention, the valve wings are extremely advantageously arranged on the valve ring in a self-supporting manner.

According to the invention, the term “self-supporting” is understood to mean that the flap wings are pivotably arranged on the flap ring without the use of a separate fastening axis, which can be designed, for example, in the form of a metal pin which connects two points on the flap ring that are opposite one another.

For the purposes of the invention, the term “pivot axis” is understood to mean an axis formed directly between or on the flap wings, about which the flap wings can be pivoted.

In the double-wing heart valve prosthesis according to the invention, a first valve wing can be arranged pivotably, for example, on two holders on the valve ring. In this case, the second flap wing can be pivoted exclusively on the first flap wing.

But it is also possible that the two flap wings, which are pivotally engaged with one another, are each pivotably arranged on one of the two axial ends of the pivot axis formed between them via a holder on the flap ring. In this case, each flap wing can be pivoted directly to the flap ring using only one holder. Each flap wing can then be arranged on the second holder indirectly via the other flap wing on the flap ring.

The flap vanes preferably have projections and / or recesses which point in the axial direction of the pivot axis in the direction of the flap ring and which engage in recesses and / or projections which are arranged on the flap ring. The flap wings can be easily attached to the flap ring be pivotally arranged. The projections can be designed, for example, as integrally formed pins. The recesses can be bores or depressions, for example.

The flap wings preferably have a crescent-shaped flat configuration with an essentially straight edge section and an arcuate edge section. The two flap wings are arranged on the flap ring so that the substantially straight edge sections face each other and are in engagement with each other. In the first position, in which the flap vanes essentially close the ring opening, the arcuate edge sections rest on or on the flap ring.

In the second position, in which the flap vanes essentially open the ring opening, the flap vanes are each pivoted independently of one another about the essentially straight edge sections which are in engagement with one another and thereby form a common pivot axis.

An angle of up to 90 ° can be included between the surfaces of the flap wing and a plane defined by the flap ring in the second position between the flap wing and the plane. The angle enclosed between the surface of a flap wing and the plane formed by the flap ring can preferably also assume smaller values, for example in each case up to 85 °, up to 80 ° or up to 75 °. Of course, the angles enclosed by the two flap vanes, each with the plane defined by the flap ring, can differ from one another and also assume different values.

According to the present invention, the first and the second flap wings are in engagement with one another and are pivotably arranged on the flap ring without a separate fastening axis. It is therefore extremely advantageous no longer to use a separate fastening axis. This facilitates the manufacture of heart valve prostheses in particular, since the assembly effort is reduced.

It is also important that the flow profile in the heart valve prosthesis according to the invention, compared to a natural heart valve, is less severely impaired than in conventionally used heart valve prostheses. This is due in particular to the fact that no separate fastening axis has to be arranged on the flap ring.

In conventional heart valve prostheses, the valve wings are articulated on a fastening axis via sleeve sections. For reasons of stability, the sleeve sections should not be less than a certain wall thickness. The fastening axis and the sleeves of the valve flaps in conventional heart valve prostheses in the ring opening, i.e. the passage opening for the blood and the valve ring represent an obstacle to flow. A further obstacle to flow are the axle bearings, which, for reasons of stability, must have a certain massiveness. These flow obstacles lead to an undesirable swirling of the blood stream, which on the one hand can lead to damage to the blood vessels and further increases the risk of thrombosis.

The heart valve prosthesis according to the invention influences the flow profile to a significantly smaller extent than the conventionally used heart valve prostheses due to the novel construction. Since in the heart valve prosthesis according to the invention no separate fastening axis and therefore no sleeve sections comprising the separate fastening axis are required, the flow resistance of the mutually engaging valve wings is significantly reduced compared to the flow resistance of conventional heart valve prostheses.

It is preferred that the first or second flap wing has at least one cutout or opening along the common pivot axis or substantially parallel to the common pivot axis with which the second or first flap wing is engaged via at least one engagement element in such a way that the two flap wings form a common pivot axis.

The at least one recess or opening can be, for example, a bore or recess which can be arranged along the straight edge section or spaced parallel to the straight edge section of a flap wing. Engaging elements engage in this at least one recess and are arranged on the other flap wing opposite each other along the straight edge section. In the simplest case, these engaging elements can be designed, for example, as hooks, eyes, clamps or spring elements.

The one or more engagement elements and the one or more recesses or openings are arranged on the flap wings on the straight edge sections or at a parallel distance from the straight edge sections, so that they are brought into engagement with one another to form a common pivot axis can.

It is preferred that the at least one recess or opening extends along the common pivot axis or substantially parallel to the common pivot axis or to the straight edge section to form at least one web-like element on at least one first flap wing and the second flap wing on the at least one web-like element is pivotably articulated.

It is preferred that the recess or opening extends parallel to the straight edge section of a flap wing. The recess or opening or recess thus preferably has an elongated shape, for example the shape of a rectangle, which preferably has rounded corners, or an oval. The longitudinal axis of such a rectangular or oval recess or recess is preferably oriented essentially parallel to the straight edge section of a flap wing. The section of the flap wing that lies between the straight edge section and the section of the flap wing, for example in the form of a rectangle with rounded corners, then has the shape of a web.

On the second flap wing corresponding engagement elements are arranged along the straight edge section, which engage in the recess of the first flap wing and at least partially, preferably partially, comprise the web-like element or the web. In this simple manner, the flap wings can be pivotally connected to one another or articulated to one another.

According to a further preferred embodiment of the invention, a plurality of recesses or openings are provided along the common pivot axis or substantially parallel to the common pivot axis to form a plurality of web-like elements arranged one behind the other in the axial direction, based on the common pivot axis, on a flap wing.

It is of course possible to provide only one recess or recess on a flap wing, this recess or recess being able to extend essentially along the length of the straight edge section of the flap wing. It is of course also possible to subdivide this recess or recess so that several, for example two, three, four or more recesses or recesses are arranged along the straight edge section of a flap wing. In this case, these cutouts or recesses are arranged one behind the other so that they can form a common pivot axis with the engagement elements arranged on the second flap wing.

Furthermore, it is preferred that several are spaced along the common pivot axis or substantially parallel to the common pivot axis Recesses or openings are provided to form a plurality of web-like elements arranged one behind the other in the axial direction on both flap wings, the recesses or perforations on the two flap wings being staggered along the common pivot axis or essentially parallel to the common pivot axis. Correspondingly, engagement elements are provided on the other flap wing at the correspondingly opposite positions along the straight edge section of the flap wing.

It is of course also possible to arrange the cutouts or recesses alternately on the two flap wings, the engagement element and cutout or recess being located opposite one another on the two flap wings at the corresponding positions along the straight edge section.

For example, the following arrangement can be provided on a first flap wing: recess - engagement element recess. The following arrangement is then provided on the second flap wing: engagement element - recess - engagement element. The flap wings can then be pivotally arranged or hinged to one another via the respective combination of recess and engagement element.

According to a further embodiment of the invention, a web-like element on a first flap wing can be latched with an engagement element on a second flap wing, the two flap wings locked together being pivotable about the common pivot axis, preferably without play.

It is preferred that an engagement element on a first flap wing partially includes a web-like element on a second flap wing, so that the two flap wings are arranged detachably and pivotably to one another.

The engagement element can, for example, in the form of, preferably resilient or elastic, clips or clip elements or at least two or two comprising spring elements. The web-like element can be designed, for example, in the form of a solid, essentially cylindrical, flattened cylindrical or rod-like body. The clips can then be locked to the web-like element, for example by pushing the clips over the web-like element and then at least partially encompassing the web-like element. The spring force of the clips prevents the clips and cylinder from falling apart. The two flap wings can be pivoted together. The two flap wings are preferably pivotally connected to one another without play.

It is preferred that the engaging element partially surrounds the web-like element, the engaging element being designed along the pivot axis or substantially parallel to the pivot axis in the manner of a hollow cylinder extending in the axial direction with a gap opening extending essentially in the axial direction for receiving the web-like element ,

In this embodiment, the hollow cylinder is not closed, but instead has a gap (gap opening) running in the axial direction with respect to the pivot axis. The width of this gap corresponds approximately to a diameter of the web-like element, so that the web-like element, which can be designed, for example, as a solid cylinder or bead-like, can be pushed or pressed through the gap and at least partially by the hollow cylinder. - Preferably partially, is included.

In this embodiment of the heart valve prosthesis according to the invention, it is extremely advantageous to exchange blood that has entered the hollow cylinder through the gap opening. This prevents blood clots from forming and depositing in the hollow cylinder.

According to a preferred development of the invention, the web-like element has a cross section perpendicular to the pivot axis with at least one long and at least one short side, the dimension of the long side being approximately the inside diameter of a cylindrical one formed in the hollow cylinder Corresponds to the cavity and the dimension of the short side is approximately the same or narrower than the gap opening of the hollow cylinder which extends essentially in the axial direction.

In this embodiment, the web-like element and the engagement element can be brought into engagement with one another without causing an expansion or expansion of the engagement element, i.e. for example, the hollow cylinder with a gap opening.

The web-like element is inserted through the gap opening into the hollow cylinder through its narrow side. After pivoting the two flap wings against each other, the web-like element is guided in the hollow cylinder, preferably without play.

The surface of the narrow side of the web-like element is preferably guided in surface contact with the inner surface of the hollow cylinder. For this purpose, it is preferred that the narrow side of the web-like element has a curvature corresponding to the curvature of the inner surface of the hollow cylinder, so that they slide past one another with as little friction as possible.

In this embodiment, the two flap wings can be pivotally arranged on one another. A separation of the two flap wings is only possible if the narrow side of the web-like element comes to lie in front of the gap opening of the hollow cylinder and can be pulled out of the hollow cylinder along the long side. In this position, the flap wings form a predetermined angle with one another. For example, the flap wings can be brought into engagement with one another if the surfaces of the flap wings enclose an angle (mounting angle) of approximately 180 ° to one another. In principle, however, the specified angle can be chosen freely.

In a preferred embodiment of the invention, the angle (mounting angle), under which the two flap wings are brought into engagement with one another, can be obtained after the flap wings have been pivotally arranged on one another can no longer be ingested on the valve ring. It is therefore not possible for the valve flaps to fall apart while the heart valve prosthesis is in use.

In this surprisingly simple manner, a reliable attachment of the flap wings to one another is made possible. In addition, this embodiment of the invention enables a stress-free arrangement and a stress-free assembly of the flap wings together. In the case of a stress-free assembly, for example, no tiny cracks or material strains can occur, as can be the case when the hollow cylinder is pushed over an, for example, cylindrically shaped web while widening the gap-like opening.

It is further preferred that the cross section of the web-like element perpendicular to the pivot axis is substantially rectangular or substantially oval.

It is preferred that the narrow side of the web-like element after being introduced into the hollow cylinder is in flat contact with the inner surface of the hollow cylinder in order to enable the web-like element and the hollow cylinder to slide against one another with as little friction and wear as possible. The short or narrow side preferably has a convex curvature, which is preferably in flat contact with the concave curvature of the inner surface of the hollow cylinder.

It is further preferred that the two flap vanes are pivotally arranged above a plane defined by the flap ring on holders provided on the flap ring.

It is further preferred that the flap wings in the first position rest on the side of the flap ring defined by the flap ring on the flap ring and pivoted in the second position in the direction of the side of the flap ring defined by the flap ring. In this advantageous development of the invention, the flap wings are arranged in a V-shape on the flap ring. The flap vanes are articulated either directly or indirectly via the other flap flaps to the retainers, the flap vanes being guided through the plane defined by the flap ring. In the first position, therefore, the flap wings rest on the inside of the flap ring on the side of the flap ring facing away from the holders.

In the first position of the flap wing, in which the ring opening is essentially closed, an angle of, for example, 100 to 130 °, preferably approximately 110 °, can be included between the surfaces of the two flap wings.

This arrangement of flap wings on the flap ring extremely advantageously allows a small depth of the entire arrangement. This is particularly advantageous when the flap wings are in the second position and essentially open the ring opening. In the second position, the flap wings only protrude beyond the flap ring to an acceptable extent. In this way, damage to surrounding vessels or tissues can be avoided after implantation of the heart valve prosthesis according to the invention.

According to a further preferred embodiment, at least one stop is provided on the holder, which limits the opening angle of at least one flap wing in the second position.

The arrangement of at least one stop on the holder prevents a flap from flipping over to the other flap wing.

The stop is preferably arranged in such a way that the flap or flaps make an angle of less than 90 ° to the plane defined by the flap ring. This ensures that when the blood flows back, the valve wings in any case from the second position, in which the valve wings essentially open the ring opening, are transferred to the first position in which the flap leaves essentially close the ring opening.

It is further preferred that the at least one engagement element is formed in a bead-like manner on at least one flap wing along the common pivot axis or at a spacing substantially parallel to the pivot axis.

It is preferred that the at least one bead-like projection is formed on at least one flap wing in such a way that a defined angle is enclosed between the two flap wings in the second position.

The formation of a bead-like approach along or parallel to the common pivot axis is a simple means to ensure that an angle is in any case included between the two flap wings in the second position. It can thus be prevented that the valve flaps come to lie one above the other and the ring opening of the heart valve prosthesis can no longer be closed.

The double wing heart valve prosthesis according to the invention must be opened and closed in the interplay of systole and diastole. The heart valve prosthesis is closed when the direction of flow of the blood is reversed, the blood flow acting on the surfaces of the two valve wings and pressing them onto or against the valve ring. So that the flap wings are easily grasped by the blood flow, it is advantageous if an angle is enclosed between the two flap wings in the second position, ie the two flap wings cannot lie flat on one another in the second position. The blood flowing back enters the space formed by the included angle between the valve flaps and presses the valve wings onto or against the valve ring, increasing the included angle, the heart valve prosthesis being closed. It is preferred that the two flap wings in the second position enclose an angle of more than 0 ° and up to 40 °, preferably from about 5 ° to about 25 °.

The angle is more preferably 10 ° to 20 °, more preferably 12 ° to 18 °. It has been shown that the response behavior of the flap vanes is excellent when the direction of blood flow is reversed, and reliable closing behavior is obtained if the angle enclosed between the flap vanes in the second position is approximately 12 ° to 18 °. It has also been shown that the flow behavior of the blood in the latter angular range is also good and a particularly small stagnation zone is obtained.

According to a further preferred embodiment, the common pivot axis of the two flap wings is arranged parallel and at a distance from a flap ring diameter on the flap ring, one flap wing having a larger area than the other flap wing.

The distance between the pivot axis and the parallel flap ring diameter is preferably approximately 4 to 22% of the inner diameter, preferably 6 to 18% of the inner diameter, of the flap ring.

It is further preferred that the larger flap wing closes in the first position about 55 to 80% of the cross-sectional area of the flap ring opening and the smaller flap wing closes in the first position about 45 to 20% of the cross-sectional area of the flap ring opening.

It is particularly preferred that the larger flap wing closes about 60 to 68% of the cross-sectional area of the flap ring opening in the first position and the smaller flap wing closes about 40 to 32% of the cross-sectional area of the flap ring opening in the first position.

It has been shown that it is of great advantage with regard to the flow profile and the flow behavior of the blood if the two Valve wings of the heart valve prosthesis are of different sizes, ie close differently sized areas of the cross section of the valve ring in the first position.

This asymmetry with regard to the area of the valve flaps in the double-wing heart valve prosthesis according to the invention enables the doctor to implant the heart valve prosthesis in accordance with the anatomical conditions on the heart and taking into account the physiological flow profile. The use of a heart valve prosthesis according to the invention with the aforementioned asymmetry with regard to the size and arrangement of the valve wings enables a significant reduction or avoidance of the formation of eddy currents and the creation of "dead water zones". This counteracts thrombosis of the valve flaps, for example. Furthermore, the occurrence of hemolysis is significantly reduced, since the flow conditions can be better adapted to the patient's anatomy and physiology.

It has proven to be very advantageous to use a heart valve prosthesis with valve wings of different sizes when implanting the heart valve prosthesis according to the invention instead of a defective mitral valve. The formation of a "dead water zone" in the ventricle of the heart chamber is avoided.

By appropriate orientation of the asymmetrical opening of the double-wing heart valve prosthesis, a very good washout of the heart tip, for example the apex cordis, can be achieved. The preferred orientation in the aortic position and in the mitral position is with respect to Viking O. Björk and Dan Lindblom tilting heart valve prostheses, "The Monstrut Björk-Shiley Heart Valve", in the Journal of the American College of Cardiology, Volume 6, No. 5 , Pages 1142-1148, November 1985. The present double wing heart valve prosthesis can be oriented accordingly in the aortic position or the mitral position during implantation. With regard to the further advantages of an asymmetrical arrangement of the flap wings, reference is made to EP 0 650 705, which is hereby incorporated by reference.

Preferably, the valve ring and / or the valve flaps are made of materials selected from the group consisting of stainless steel, titanium, titanium carbide, carbon-boron compounds, pyrolytic carbon and mixtures thereof.

The surface can optionally be coated with pyrolytic carbon (polycarbonate). The flap wings and / or the flap ring can also contain stiffening and / or reinforcing inserts. These inlays can be made, for example, from titanium, an aluminum-titanium alloy, a cobalt alloy (for example HAYNES 23 or HAYNES 25) and / or from other known suitable materials.

The flap ring can have a height of 3 to 7 mm and a diameter of 12 to 29 mm, for example. However, the exact dimensions depend on the application and the age of the patient. The thickness of the flap wings can be, for example, in a range from 0.25 mm to 2 mm, preferably 0.5 mm to 1.5 mm. The thickness of the flap wings is more preferably approximately 0.6 mm to 0.8 mm.

According to a further preferred embodiment, the flap ring on the side facing away from the ring opening has circumferential boundaries along the outer circumference, forming a circumferential groove.

Textile fabric is preferably arranged along the circumferential groove.

The textile tissue arranged in the groove running around the outer circumference of the valve ring enables the heart valve prosthesis to be attached to the heart tissue. The textile fabric is usually arranged in the groove in the form of a seam ring. The seam ring can be inserted into the groove on the valve ring inserted plastic thread or tape, preferably Dacron ^® , and a fabric protruding from the groove made of plastic, preferably of Teflon ^® fibers. Furthermore, carbon fibers (carbon fibers) or fibers coated with carbon are preferably used. Carbon fibers can be produced, for example, from carbonized polyacrylonitrile (PAN) or from carbonized cellulose, for example carbonized cellulose acetate.

The assembly of the double wing heart valve prosthesis according to the invention is very simple. The material from which the flap wing and / or the flap ring is made has a slight extensibility or elasticity, so that the flap wings are pivotally arranged in the flap ring by the mutually engaging flap wings, for example under pressure, with their projections be locked in the respective recesses of the brackets.

The two flap wings can, for example, be articulated to one another in a first step and correspondingly locked to the flap ring in a second step. For this purpose, if necessary, the valve ring can be briefly slightly oval-shaped, for example by applying pressure, and can engage with one another. standing flap wings are used with their projections and / or recesses in the recesses and / or projections of the flap ring. After removal of the pressure applied to the valve ring, it takes on its essentially circular shape again and the valve wings are pivotally arranged on the valve ring.

The assembly is therefore much easier than with conventional heart valve prostheses, in which the insertion of an axis in aligned bores is required, possibly even using additional axle bearings. Furthermore, the bores of the articulated valve flaps in conventional heart valve prostheses must be aligned exactly, since otherwise the valve flaps can be jammed, ie they can no longer be freely pivoted in the bloodstream. The invention is further illustrated below with reference to figures which illustrate exemplary embodiments of the invention. It shows

1 is a perspective view of a double wing heart valve prosthesis according to the invention,

2a shows an embodiment of the two flap wings according to the invention in a separate form,

2b is a representation of a further embodiment of the two flap wings according to the invention in a separate form,

3 shows a sectional illustration of a heart valve prosthesis according to the invention vertical to the common pivot axis,

4 is an illustration of a section in the vertical direction through a swivel axis which can be used in the heart valve prosthesis according to the invention,

5 is a top view of the heart valve prosthesis according to the invention, the two valve wings closing the ring opening.

In Fig. 1, a double wing heart valve prosthesis according to the invention is shown in perspective in the second position, in which the valve wings (2) and (3) essentially open the opening (4) of the valve ring (1). The flap wings (2) and (3) enclose an angle (16). The flap wings (2) and (3) are pivotally arranged on the flap ring (1) and can be pivoted independently of one another. In this case, projections or pins (19) are provided on the large flap wing (2) along the common pivot axis (5) and engage in recesses (20) in the holders (14). The small flap wing (3) is in this embodiment only in engagement with the larger flap wing (2). The brackets (14) are in this representation above the plane (13) defined by the flap ring (1) arranged. The flap wings (2,3) protrude through the flap ring (1). In the first position, in which the flap wings (2, 3) essentially close the ring opening (1), the flap wings (2, 3) lie on the inside of the flap ring (1) on the side of the flap ring (1) facing away from the holders (14). 1) on (not shown).

The flap wings (2) and (3) are each limited in scope by an arcuate edge section (21) and by a straight edge section (22), which coincides with the common pivot axis (5) in this illustration.

The two flap wings (2) and (3) are arranged so that they form a common pivot axis (5). In the present case, the common pivot axis (5) coincides with the straight edge sections of the flap wings (2) and (3). A circumferential groove (18) is provided along the outer circumference of the flap ring (1). A suture ring, not shown, can be arranged on this circumferential groove (18), via which the heart valve prosthesis can be attached to the heart tissue, for example by sewing. The flap wings (2) and (3) have a differently sized area. The flap wing (2) has a larger area and consequently covers a larger part of the cross-sectional area of the ring opening (4) of the flap ring (1). The flap wing (3) has a smaller area and consequently covers a smaller part of the cross-sectional area of the opening (4) of the flap ring (1).

The thickness of the flap wings (2) and (3) can be, for example, in the range from approximately 0.6 mm to 0.8 mm.

FIG. 2a shows the valve wings (2) and (3) used in the embodiment of the heart valve prosthesis shown in FIG. 1 in a separate form.

The larger-area flap wing (2) has a recess or opening or recess (6). The recess (6) extends parallel and at a distance from the straight edge section (22) of the flap wing (2) over almost the entire length of the edge section (22). The recess (6) is essentially rectangular with rounded corners. A web-like element (8) is formed between the recess (6) and the edge section (22). A pin (19) is arranged at the axial end of each straight edge section (22) of the flap wing (2). The flap wing (2) is pivotably arranged in bores or depressions (20) of the holders (14) via the pin (19).

The flap wing (3), which is smaller in area, has a hollow cylinder (9) along the straight edge section (22) with a gap opening (10) running parallel to the straight edge section (22). The gap width of the gap opening (10) corresponds approximately to the thickness of the web-like element (8) on the larger flap wing (2). The flap wings (2) and (3) can be pivotally connected to one another by pushing the web-like element (8) through the gap opening (10) of the hollow cylinder (9) and pivoting the two flap wings (2, 3) against one another. In a preferred embodiment, the thickness of the web-like element (8) is identical to the thickness of the flap wing (2) and / or (3).

2b shows a further design option for pivotably connecting the flap wings (2) and (3) to one another. In this embodiment, a recess (6), a web-like element (8) and a hollow cylinder (9) are arranged on each flap wing. The web-like element (8) and the hollow cylinder (9) are offset from one another on the two flap wings (2, 3) and each extend approximately over half and along the straight edge section (22). Furthermore, each flap wing (2, 3) has a pin (19) which extends in the axial direction at the end of the edge section (22) with the web-like element (8). The pin (19) can of course also be provided at the end of the straight edge section (22) at which the hollow cylinder (9) is arranged.

In this embodiment, the forces acting on the respective web-like element (8) are lower compared to that shown in FIG. 2a Embodiment. In the present embodiment (FIG. 2b), the forces acting on the flap wings (2, 3) are distributed over the web-like elements (8) on each flap wing (2, 3).

Fig. 3 shows a heart valve prosthesis according to the invention in a sectional view, perpendicular to the common pivot axis (5). The flap ring (1) has a circumferential groove (18) for fastening a seam ring, not shown.

The small flap wing (3) and the large flap wing (2) are articulated on the brackets (14) via the common pivot axis (5). An angle (16) is enclosed between the flap wings (2, 3) arranged in a V-shape. The flap wings (2, 3) protrude through the flap ring (1) onto the side of the flap ring (1) facing away from the brackets (14). The small flap wing (3) is shown in the first position (closed position). The flap wing (3) lies against the inside of the flap ring (1). The large flap wing (3) is shown in the second position (open position) and protrudes through the ring opening (4).

The web-like element (8) can be seen in cross-section in engagement with the hollow cylinder (9). The gap-like opening (10) is arranged such that the two flap wings (2, 3) cannot be separated from one another either in the first position closing the flap ring (1) or in the second position essentially releasing the flap ring (1). For this purpose, it is preferred to arrange the gap opening (10) in the hollow cylinder (9) directly opposite the flap wing (2) or (3) arranged on the hollow cylinder (9).

Fig. 4 shows the arrangement of web-like element (8) and hollow cylinder (9) in an enlarged view. In this illustration it can be seen that the short or narrow side (12) of the web-like element (8) has a concave surface curvature which is complementary to the convex curvature of the inner surface of the hollow cylinder (9). This means that the web-like element (8) preferably has a sliding surface on its short or narrow side, the degree of curvature of which corresponds to the degree of curvature Inner surface of the hollow cylinder (9) is matched in order to obtain the lowest possible friction and thus the lowest possible wear.

Furthermore, the dimension of the short or narrow side (12) corresponds approximately to the width of the gap opening (10). The web-like element (8) also has a long side (11), the dimensions of which correspond approximately to the inside diameter of the hollow cylinder (9). In this way there is a pivotable arrangement of the flap wings

(2) and (3) possible together. This configuration extremely advantageously enables the two flap wings (2, 3) to be arranged against one another essentially without play. The gap opening (10) on the hollow cylinder (9) is on the flap wing

(3) facing away. A separation of flap wings (2) and (3) is only possible if the angle (16) enclosed between the flap wings (2,3) is 180 °. It is therefore not possible to separate the flap wings (2, 3) if they are arranged on the flap ring (1) in the V-shape shown in FIGS. 1 and 3 on the brackets (14).

FIG. 5 shows a top view of the heart valve prosthesis according to the invention from FIG. 1. The brackets (14) are arranged on the side facing the viewer. The flap wings (2) and (3) protrude through the flap ring (1) and lie on the inside of the flap ring (1) on the side of the flap ring (1) facing away from the viewer. This illustration shows the heart valve prosthesis in the closed position, in which the valve wings (2) and (3) essentially close the ring opening (4). An essentially rectangular recess (6) with rounded corners is provided in the large flap wing (2) to form a web-like element (8). The longitudinal axis of the recess (6) extends essentially parallel to the common pivot axis (5) and along the straight edge section (22) of the large flap wing (2). The web-like element (8) is partially surrounded by the hollow cylinder (9), which has a gap opening (10). The gap opening (10) extends over the entire length of the hollow cylinder (9) and essentially parallel to the common pivot axis (5). The large flap wing (2) is pivotably arranged in depressions (20) on the flap ring (1) via two pins (19), each of which extends in the axial direction of the common pivot axis (5) in the direction of the flap ring (1). The wells (20) are embedded in the brackets (14). The small flap wing (3) is articulated exclusively on the large flap wing (2) via the hollow cylinder (9) with a gap opening (10), the hollow cylinder (9) being in engagement with the web-like element (8).

Claims

claims

1. Double wing heart valve prosthesis with a substantially circular, an annular opening (4) having a valve ring (1), a first and a second valve wing (2,3), the valve wing (2,3) from a first position in which the Flap wings (2, 3) essentially close the ring opening (4) into a second position, in which the flap wings (2, 3) essentially open the ring opening (4), can be pivoted independently of one another, characterized in that the flap wings ( 2,3) are in engagement with each other and on the flap ring

(1) are arranged pivotably without a separate fastening axis.

2. Double-wing heart valve prosthesis according to claim 1, characterized in that the first and the second valve wing (2,3) about a common pivot axis (5) are arranged pivotally on the valve ring (1). , -

3. Double wing heart valve prosthesis according to claim 2, characterized in that the first or second valve wing (2,3) along the common pivot axis (5) or substantially parallel to the common pivot axis (5) at least one recess or opening (6 ), with which the second or first flap wing (3, 2) engages via at least one engagement element (7) such that the two flap wings (2, 3) form a common pivot axis (5).

4. double wing heart valve prosthesis according to claim 3, characterized in that the at least one recess or opening (6) along the common pivot axis (5) or substantially parallel to the common pivot axis (5) with the formation of at least one web-like element (8) on at least one first flap wing (2 , 3) and the second flap wing (3, 2) can be pivoted on the at least one web-like element (8).

5. Double wing heart valve prosthesis according to claim 4, characterized in that along the common pivot axis (5) or substantially parallel to the common pivot axis (5) a plurality of recesses or openings (6) to form a plurality of web-like elements arranged one behind the other in the axial direction (8) are provided on a flap wing (2,3).

6. Double-wing heart valve prosthesis according to claim 4, characterized in that along the common pivot axis (5) or substantially parallel to the common pivot axis (5) a plurality of recesses or openings (6) to form a plurality of web-like elements arranged one behind the other in the axial direction (8) are provided on both flap wings (2, 3), the recesses or openings (6) on the two flap wings (2, 3) along the common pivot axis (5) or essentially parallel to the common pivot axis (5) are arranged offset to each other.

7. Double wing heart valve prosthesis according to one of claims 4 to 6, characterized in that a web-like element (8) on a first valve wing (2,3) with an engagement element (7) on a second valve wing (3,2) can be locked, the two latched flap wings (2, 3) being pivotable about the common pivot axis (5), preferably without play.

8. Double wing heart valve prosthesis according to one of claims 4 to 7, characterized in that an engagement element (7) on a first valve wing (2,3) partially comprises a web-like element (8) on a second valve wing (3,2), so that the two flap wings (2, 3) are arranged to be detachable and pivotable.

9. double-wing heart valve prosthesis according to claim 8, characterized in that the engagement element (7) partially comprises the web-like element (8), the engagement element (7) along the pivot axis (5) or substantially parallel to the pivot axis (5) according to Art an axially extending hollow cylinder (9) with a substantially axially extending gap opening (10) for receiving the web-like element (8) is formed.

10. Double wing heart valve prosthesis according to claim 9, characterized in that the web-like element (8) perpendicular to the pivot axis (5) has a cross section with at least one long (11) and at least one short (12) side, the dimension of the long side (11) corresponds approximately to the inside diameter of a cylindrical cavity formed in the hollow cylinder (9) and the dimension of the short side (12) is approximately the same or narrower than the gap opening (10) of the hollow cylinder (essentially extending in the axial direction). 9) is.

11. Double-wing heart valve prosthesis according to claim 10, characterized in that the cross section of the web-like element (8) perpendicular to the pivot axis (5) is substantially rectangular or substantially oval.

12. Double-wing prosthetic heart valve according to one of the preceding claims, characterized in that that the two flap wings (2, 3) are pivotably arranged above a plane (13) defined by the flap ring (1) on brackets (14) provided on the flap ring (1).

13. Double wing heart valve prosthesis according to claim 12, characterized in that the valve wing (2,3) in the first position on the side facing away from the brackets (14) of the plane defined by the valve ring (1) (5) on the valve ring (1) abut and are pivoted in the second position in the direction of the side facing away from the holders (14) of the plane (13) defined by the flap ring (1).

14. Double-wing heart valve prosthesis according to one of claims 12 to 14, characterized in that on the holder (14) at least one stop (15) is provided which the opening angle (16) of at least one valve wing (2,3) in the second position limited.

15. Double-wing heart valve prosthesis according to one of the preceding claims, characterized in that the at least one engagement element (7) on at least one valve wing (2,3) along the common pivot axis (5) or substantially parallel spaced to the pivot axis (5) integrally formed is.

16. Double-wing heart valve prosthesis according to claim 15, characterized in that the at least one bead-like extension is formed on at least one valve wing (2, 3) in such a way that a defined angle (16) between the two valve wings (2, 3) in the second position ) is included.

17. Double flight heart valve prosthesis according to one of the preceding claims, characterized in that the two valve wings (2, 3) form an angle with one another in the second position

(16) from more than 0 ° and up to 40 °, preferably from about 5 ° to about 25 °.

18. Double-wing heart valve prosthesis according to one of claims 2 to 18, characterized in that the common pivot axis (5) of the two valve wings (2,3) is arranged in parallel and at a distance from a valve ring diameter (17) on the valve ring (1), wherein a first flap wing (2) has a larger area than the second flap wing (3).

19. Double-wing heart valve prosthesis according to claim 18, characterized in that the distance of the pivot axis (5) to the parallel valve ring diameter

(17) is about 4 to 22% of the inside diameter, preferably 6 to 18% of the inside diameter, of the valve ring (1).

20. Double-wing heart valve prosthesis according to claim 18 or 19, characterized in that the area-larger valve wing (2) closes in the first position about 55 to 80% of the cross-sectional area of the ring opening (4) and the area-smaller valve wing (3) in the first Position closes about 45 to 20% of the cross-sectional area of the ring opening (4).

21. Double-wing heart valve prosthesis according to claim 18 or 19, characterized in that the larger valve flap (2) in the first position closes about 60 to 68% of the cross-sectional area of the ring opening (4) and the smaller valve flap (3) in the first Position closes about 40 to 32% of the cross-sectional area of the ring opening (4).

22. Double-wing heart valve prosthesis according to one of claims 14 to 21, characterized in that on the holder (14) at least one stop (15) is provided which limits the opening angle (16) of the larger valve wing (2) in the second position.

23. Double-wing heart valve prosthesis according to one of the preceding claims, characterized in that the valve ring (1) on the side facing away from the ring opening (4) has lateral circumferential boundaries along the outer circumference, forming a circumferential groove (18).

24. Double-wing heart valve prosthesis according to claim 23, characterized in that textile tissue is arranged along the circumferential groove (18).

25. Double-wing heart valve prosthesis according to one of the preceding claims, characterized in that the valve ring (1) and / or the valve wings (2,3) are made of materials selected from the group consisting of stainless steel, titanium, titanium carbide, Carbon-boron compounds, pyrolytic carbon and mixtures thereof.