WO2009156471A1 - Prosthetic heart valve and method for making such a valve - Google Patents

Prosthetic heart valve and method for making such a valve Download PDF

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Publication number
WO2009156471A1
WO2009156471A1 PCT/EP2009/057970 EP2009057970W WO2009156471A1 WO 2009156471 A1 WO2009156471 A1 WO 2009156471A1 EP 2009057970 W EP2009057970 W EP 2009057970W WO 2009156471 A1 WO2009156471 A1 WO 2009156471A1
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WO
WIPO (PCT)
Prior art keywords
heart valve
prosthetic heart
mould
characterised
valve
Prior art date
Application number
PCT/EP2009/057970
Other languages
French (fr)
Inventor
Carlos Vonderwalde
Isabel PÉREZ SERRANOS
Lluís DUOCASTELLA CODINA
Aniceto LÓPEZ RODRÍGUEZ
Original Assignee
Iberhospitex, S.A.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to EP08159129 priority Critical
Priority to EP08159129.9 priority
Application filed by Iberhospitex, S.A. filed Critical Iberhospitex, S.A.
Publication of WO2009156471A1 publication Critical patent/WO2009156471A1/en

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Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/24Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices
    • A61F2/2412Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices with soft flexible valve members, e.g. tissue valves shaped like natural valves
    • A61F2/2415Manufacturing methods
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/24Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices
    • A61F2/2409Support rings therefor, e.g. for connecting valves to tissue
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/24Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices
    • A61F2/2412Heart valves ; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices with soft flexible valve members, e.g. tissue valves shaped like natural valves
    • A61F2/2418Scaffolds therefor, e.g. support stents

Abstract

The present invention relates to a method of making a prosthetic heart valve comprising the steps of placing a piece of biological tissue (12) in or over a mould (10), and simultaneously tanning said tissue and shaping it to an appropriate shape. Furthermore, it relates to a prosthetic heart valve of a single piece of biological tissue, said valve comprising a cylindrical base and leaflets, characterised in that said cylindrical base and leaflets have a continuous peripheral wall.

Description

Prosthetic heart valve and method for making such a valve

The present invention relates to a prosthetic heart valve from biological tissue and to a method of making such a valve.

The human heart has a right side and a left side. The function of the right side of the heart is to collect de-oxygenated blood from the body, in the right atrium, and pump it, via the right ventricle, into the lungs so that carbon dioxide can be dropped off and oxygen picked up. The left side collects oxygenated blood from the lungs into the left atrium. From the left atrium the blood moves to the left ventricle which pumps it out to the body.

Starting in the right atrium, the blood flows through the tricuspid valve to the right ventricle. Here it is pumped out through the pulmonary valve and travels through the pulmonary artery to the lungs. From there, blood flows back through the pulmonary vein to the left atrium. It then travels through the mitral valve to the left ventricle, from where it is pumped through the aortic valve to the aorta. From the aorta, the blood is divided between major arteries which supply the upper and lower body. The tricuspid valve, pulmonary valve and aortic valve each comprise three leaflets (or cusps). The mitral valve has two leaflets. All heart valves are non-return valves, i.e. they ensure blood flow in only one direction and open under the influence of pressure differences. The mitral valve and tricuspid valve ensure that blood can flow from the atria to the ventricles and not the other way. The pulmonary valve and aortic valve ensure blood flow from the ventricles to the pulmonary vein and aorta respectively.

A malfunctioning heart valve may result in either backward flow (regurgitation) or impeded forward flow (stenosis). Certain heart valve pathologies may necessitate the complete surgical replacement of the natural heart valves with heart valve prostheses.

US 4,441 ,216 discloses a method for making a replacement heart valve. In this document, the replacement heart valve is made by taking a piece of pericardial tissue, tanning the tissue and cutting three leaflets. The leaflets are then connected to each other and to a stent via stitching. US 2003/0130729 describes a percutaneously implantable replacement heart valve device. The replacement heart valve device comprises a stent member and a biological tissue artificial valve means disposed within the inner space of the stent member. The method of making the replacement heart valve device involves taking a rectangular fragment of animal pericardium, treating, drying, folding and rehydrating it in such a way that it forms a two- or three-leaflet valve. At its cylindrical base, two borders are stitched together.

It is an object of the present invention to provide an improved prosthetic heart valve and an improved method of making a prosthetic heart valve. This object is achieved by a method of making a prosthetic valve according to claim 1 and a prosthetic heart valve according to claim 8.

According to one aspect of the invention, the method of making a prosthetic heart valve comprises the steps of placing a piece of biological tissue in or over a mould, and simultaneously tanning said tissue and forming it to an appropriate shape.

Traditionally, biological tissue is tanned in a first step. After tanning, the tissue is cut into several pieces of appropriate shape. These pieces are then sutured back together to form the prosthetic heart valve. Inventors however have found that the biological tissue can be tanned and given the appropriate shape simultaneously by placing it in or over a mould and applying appropriate tension. There is thus no need for cutting tissue into several pieces and then suturing them back together. The result is a heart valve that resembles a human heart valve much better. Since the heart valve is from a single biological tissue (thus also from a single animal), the tissue of the heart valve is more homogeneous. Additionally, no sutures are required. Sutures in a prosthetic heart valve device are problematic for a number of reasons. They cause local stress concentrations and limit the life time of a prosthetic heart valve and are the main cause for leakage occurring in prosthetic heart valves. Also, a prosthetic heart valve aims at being anatomically correct in comparison to a normal heart valve, and sutures are not anatomically correct.

Preferably, in some methods according to the invention, the step of placing the biological tissue in or over a mould comprises using two moulds, a positive mould with substantially the desired shape of the valve and a negative mould with a negative shape of said positive mould. Using two moulds with a positive and a negative shape is advantageous in the process of shaping the heart valve.

Optionally, said step of placing the biological tissue in or over a mould comprises the steps of placing the tissue over said positive mould and then placing said negative mould over the biological tissue. Another option is that said step of placing the biological tissue in or over a mould comprises the steps of placing the biological tissue in said negative mould and then placing the positive mould within the negative mould.

Optionally, the mould that the tissue is placed over has a bottom ring and said step of placing said biological tissue over a mould includes folding the tissue around said bottom ring. The result of folding the tissue around such a bottom ring is to have a heart valve with a ring which can be fixed to a support structure. When the prosthetic heart valve device (prosthetic heart valve and support structure) is positioned appropriately in a patient's body (e.g. for an aortic heart valve, at the connection of the heart to the aorta), leaks around the outside of the valve may, in certain cases, be avoided. Optionally, said bottom ring may be a conical bottom ring. This shape may be given to further reduce leaks around the valve. Yet another option is that the bottom ring is ridged or undulated, which may also be beneficial in reducing leaks around the valve.

However, the appropriate mould and also whether a plurality of moulds should be used, depends to a large extent on the desired shape of the valve. In this sense, two kinds of valves should be distinguished: "open" valves and "closed" valves. "Open" valves have a substantially open cylindrical shape in a relaxed state. Their leaflets are merely defined by parts of the cylinder that can move inwardly when appropriate pressure conditions are created. "Closed" valves have a partly cylindrical shape which however is closed by three (or two) leaflets at one side. In use, under suitable pressure, these leaflets may move outward to open and let blood pass. Open and closed valves work in the same way, but their default state is different (respectively open and closed). Clearly, the mould to be used for shaping the valve depends on the desired end shape of the valve.

Preferably, the tanning step occurs by subjecting the biological tissue to a glutaraldehyde solution. The tanning step occurs simultaneously with the shaping of the heart valve, with the biological tissue placed in or over a mould. The goal of the tanning step is to make the tissue biocompatible. Other aldehydes are known in the art and may be used. The best results have been obtained with glutaraldehyde solutions with concentrations between 0.1 and 1 %, preferably around 0.65%. Optionally, in the method according to the invention, said step of forming the tissue to an appropriate shape includes applying tension to the tissue. By applying tension (e.g. by pulling, by using two moulds or by creating a vacuum) in appropriate points at appropriate moments, the tissue takes the desired form of the heart valve. In some embodiments, the method of making a prosthetic heart valve includes an additional step of cutting the biological tissue to form the leaflets of the valve. The whole process was started with a single piece of biological tissue. After the tissue has been given the appropriate shape to function as a heart valve and has been tanned, in some embodiments, the leaflets are formed by making cuts in the single piece of biological tissue and as such "opening" the tissue. This way no form of suturing is required to form the leaflets. As mentioned before, sutures are a source of inconvenience in prosthetic heart valves. These cuts may be made when the tissue is placed over the mould, using the shape of the mould as a guide in the cutting process. The cuts may also be made after it has been released from the mould and fixed on a support structure, together forming a heart valve device, hereinafter further described. This may be a bit more complicated, but it has the advantage of having the valve in its mounted position when cutting. This avoids possible cutting errors due to the valve being mounted in a support structure slightly differently. It is however also possible to use an additional mould or guide for the cutting process or to cut without any additional guide or tool.

According to a second aspect of the invention, a method of making a prosthetic heart valve device is provided, said method comprising the steps of making a prosthetic heart valve according to the invention and the additional step of attaching the prosthetic heart valve to a support structure. The support structure, in use, has the function of supporting the heart valve, and mostly supporting the leaflets of the heart valve to keep them in their desired shape.

According to another aspect of the invention, a prosthetic heart valve of a single piece of biological tissue is provided, said valve comprising a substantially cylindrical base and leaflets, characterised in that said cylindrical base and leaflets have a continuous peripheral wall. The single piece of biological tissue ensures a homogeneous heart valve, and the continuous peripheral wall avoids the need of any sutures (which are known to cause problems during the life-time of the heart valve).

Preferably, the heart valve is formed using a method according to the invention. The method of making a prosthetic heart valve described here within is the most advantageous way of providing a heart valve of homogeneous tissue without any sutures. In an aspect of the invention, the invention provides a prosthetic heart valve of a single piece of biological tissue, said valve being an open valve and having a continuous peripheral wall.

In another aspect according to the invention, a prosthetic heart valve device is provided comprising a prosthetic heart valve of a single piece of biological tissue and a support structure for supporting said valve, said valve comprising a cylindrical base and leaflets, said cylindrical base and leaflets having a continuous peripheral wall. The support structure is provided such that the leaflets in use can maintain their original shape and function properly. Any suitable support structure may be used. In some embodiments, the support structure of the heart valve device comprises three legs for fixing three leaflets of the valve. The present invention is especially aimed at prosthetic aortic heart valves. Aortic heart valves comprise three leaflets. However, within the scope of the present invention, any suitable support structure may be used such as e.g. balloon expandable or self-expandable stents.

A preferred way of connecting the leaflets to the support structure is through suturing. It is to be noted that these sutures are not sutures for closing or forming the heart valve (the peripheral wall of the heart valve is continuous); the heart valve itself is completely free from sutures and thus has a continuous peripheral wall. The sutures serve merely to attach the valve to the support structure. Another preferred way of fixing the leaflets of the valve to the support structure is by using bendable piercing members (like staples) along the support structure. It is possible to provide the support structure with these piercing members already during its manufacturing. It is also possible to provide them separately. These piercing members can be bent around the support perforating the tissue of the heart valve, and as such securing the valve in place. Other mechanical means, such as clamps or clips could also be used for fixing the leaflets along the support structure.

In some embodiments, the support structure comprises two annular discs for positioning the prosthetic heart valve in place, said two annular discs interconnected by a cylinder. By using two annular discs interconnected by a cylinder, the support structure can be positioned at the junction of e.g. the left heart ventricle and the aorta, in the place of the original malfunctioning heart valve (if the prosthetic heart valve is an aortic heart valve). Additionally, in combination with the heart valve comprising a bottom ring (if a mould with a bottom ring has been used) it avoids leaks around the prosthetic heart valve device.

Preferably, the support structure of the heart valve device is collapsible. Optionally, the support structure is made from nitinol. Heart valve replacement can occur in open heart surgery, but preferably it occurs percutaneously by using a catheter or in minimally invasive surgery, such as thoracotomy or sternotomy (or similar). To enable this, the support structure needs to be collapsible. One way of giving the support this collapsibility is to manufacture it (or its parts) with nitinol. Nitinol is a shape memory alloy and additionally has the necessary characteristic of biocompatibility. Alternatively, it is possible to use other shape memory alloys. A valve device with a nitinol support structure as such is self-expandable. It can expand to its proper size and shape once delivered in the appropriate position. Alternatively, the valve device may be made with a different support structure which may expand to its desired form using other known conventional means, such as by mechanical means or by a balloon. One known alternative way is e.g. the use of a balloon expandable stent as the support structure. Materials which may be used for the support structure in this case are e.g. stainless steel and cobalt chromium alloys. The present invention is especially aimed at providing prosthetic heart valves and heart valve devices for replacing aortic and pulmonary heart valves. However, the invention may explicitly also be used to provide a prosthetic tricuspid or mitral valve. These and further possible embodiments of the invention and their advantages will be explained, only by way of non-limiting example, with reference to the appended figures, in which:

Figure 1 (a) is a perspective view of a preferred mould used in the method according to the present invention;

Figure 1 (b) is a perspective view of another preferred mould used in the method according to the present invention;

Figure 1 (c) is a top view of the mould shown in figure 1 (a);

Figure 1 (d) is a perspective view of yet another preferred mould used in the method according to the present invention;

Figures 2(a)-2(d) show perspective views of different steps in a preferred method of making a "closed" valve according to the present invention;

Figures 2(e)-2(h) show perspective views of different steps in a preferred method of making an "open" valve according to the present invention;

Figures 3(a)-3(c) show perspective, schematic views of three possible heart valves according to the invention.

Figures 4(a)-4(c) show perspective views of support structures that may be used in heart valve devices according to the present invention;

Figures 5(a) and 5(b) shows in perspective view two steps in a preferred method of making a "closed" heart valve device according to the present invention;

Figure 5(c) shows the top view of the heart valve device shown in 5(a);

Figure 5(d) shows a perspective view of an "open" heart valve device according to an embodiment of the present invention.

Before the heart valve is actually made, suitable tissue needs to be harvested. Preferably, biological tissue is tissue from bovine, equine or porcine pericardium. In principle, other biological tissue may be used as well. Preferably, the whole pericardial sac is harvested and is inspected for defects, such as blood in the tissue, or anatomical defects. Then the fat tissue is removed. Once a clean pericardium has been selected, it is normally put in a clean container in sterile distilled water or similar for cleansing and transportation. During the cleansing, the distilled water may be refreshed a number of times. The tissue is then transported to the laboratory where the heart valve is going to be made.

From the selected pericardium, the most suitable tissue must now be selected. Positive criteria used for this selection may include: homogeneous colour and texture of tissue, well hydrated, absence of blood, absence of grooves and homogeneous thickness (depending on the application, the desired thickness may be different, e.g. of at least a 100 microns. The invention is not limited in this sense.). A piece of tissue is then cut from the pericardium. This piece of tissue should of course be big enough to be placed over the mould used in the manufacturing process, and the exact dimensions of the selected piece may vary with the desired size of the heart valve and the mould chosen.

With reference to figures 1 (a) and (b), two possible moulds (10) which may be used in the method according to the invention are shown. In figure 1 (a), the mould includes a bottom ring (11 ), a cylindrical base (19) for forming a continuous cylindrical base in the resulting heart valve, and a three winged structure at the top for forming three leaflets. In figure 1 (b), the mould does not have such a bottom ring, but has the same cylindrical base and the same three winged structure. In another mould that may be used, the bottom ring may be conical in shape (not disclosed in any figure). Yet another option is that the bottom ring (11 ) of the mould may be ridged or undulated (not disclosed in any figure) such that the resulting heart valve also comprises an undulated or ridged bottom ring. Both figures 1 (a) and 1 (b) refer to moulds that are suitable for making a "closed" heart valve. "Closed" valves have a partly cylindrical shape which is closed by three (or two) leaflets at one side. In use, under suitable pressure, these leaflets may move outward to open and let blood pass. The moulds shown in figures 1 (a) and 1 (b) have an appropriate shape with (in this case) three wings (17) for forming the leaflets of the heart valve.

Figure 1 (c) shows a top view of the mould shown in figure 1 (a). It more clearly shows the three wings (17) of the structure at the top of the mould. The cylindrical base (19) indicated in figure 1 (a) may also be more pronounced, i.e. the point where the base transforms into the leaflets may be higher. Figure 1 (d) shows a cylindrical mould, which is suitable for making an "open" valve. "Open" valves have a substantially open cylindrical shape in a relaxed state. Their leaflets are merely defined by parts of the cylinder that can move inwardly when appropriate pressure conditions are created. Figures 2(a) and 2(b) show the first steps according to the invention.

The mould (10) shown in these figures has a substantially flat bottom ring. As has been mentioned before, this ring may also be conical or the mould may not have a ring. The biological tissue (12) has been made available and it is placed over the mould. The tissue placed over the mould is shown as hatched in this figure. The top side of the mould should be covered as completely as possible, in order for the tissue to take the shape of the mould. The goal of the bottom ring of the mould is that by covering the ring with tissue, a ring is formed which may reduce, in certain cases, the leaks around the valve when in use. Tension is applied to the tissue to shape it more accurately. A negative mould (15), which has the negative shape of the positive mould (such as shown in figure 2(c)) may be placed over the tissue to help shape the tissue. At this point, the tanning process begins. The tissue including the mould (and optionally a second mould) is placed in a tanning solution. Preferably, a glutaraldehyde solution with a concentration between 0.1 % and 1 %, most preferably around 0.65%, is used. It is important to note that the shaping of the tissue and the tanning of the tissue occur simultaneously. This allows the valve to be formed from a single piece of biological tissue without any sutures.

The order of using the two moulds may also be reversed. The tissue may first be placed in negative mould (15) and then positive mould (10) may be used to help the tissue take the proper shape. In the following, the tanning and shaping process is described in a method using two moulds. It should however be noted that the tanning and shaping may also occur using a single mould. Steps of an alternative method according to the present invention are illustrated in figures 2(e) - 2(g). Figure 2(e) shows a single piece of biological tissue (12) and a mould (10'). The mould (10') is suitable for making an "open" valve. The biological tissue is placed over the mould (10'), similarly to the steps described before with respect to figures 2(a) and 2(b). Also, when forming an "open" valve, a negative mould (15') may be used. This is illustrated in figure 2(g). Negative mould (15') has the negative shape of positive mould (10').

The tanning (and shaping) process may pass through various phases. One possibility is that after some 15 minutes, the negative mould is taken away and it is ensured that the tissue takes the desired shape of the mould by forcing it in the appropriate shape. The tissue may extend beyond the borders of the mould, since some form of tension may have been applied to the tissue to give it the appropriate shape. In a next step, the tissue, still on the positive mould, is placed in a fresh glutaraldehyde solution for a few hours, e.g. approximately two hours.

An alternative possibility is that the positive mould is taken away after some 15 minutes and the tissue stays positioned in the negative mould. It is important to also ensure in this case that the tissue assumes the desired shape, i.e. the tissue is manipulated in such a way that it has no folds. Then, the tissue, still in the negative mould, is placed in a glutaraldehyde solution for a few hours, e.g. approximately two hours.

Optionally, the next step may be to cut the tissue along the three wings of the mould to form three leaflets. This is illustrated in figure 2(d). Suitable scissors (13) or other cutting means may be used. The cut may be performed on the top of the union of the leaflets, e.g. by cutting parallel to the vertical plane of the valve. Alternatively, the cut may be performed slightly below the union of the leaflets by cutting in a plane perpendicular to the vertical plane of the valve. Additionally, it is possible to use both cutting methods. In the case of the open valve of figure 2(h), cuts are also made to provide a valve with a cylindrical shape, which is open on both sides. Notice that in this case, no cuts are made to form leaflets of the valve.

After these hours in the glutaraldehyde solution, the remaining mould is removed when it is ensured that the tissue has taken the appropriate shape. Yet another possibility is leaving the valve in or over the mould for a longer time. The benefit of removing the mould after a while is to put the tissue in contact with the glutaraldehyde along its entire surface, which accelerates the tanning process. By keeping the valve in the mould longer, the tanning process may be slower, but the valve will keep its shape better. A way to balance both these advantages and disadvantages can be to provide the mould with a plurality of perforations along its surface or to make the mould out of a meshed material, such that it is permeable to a certain extent.

The tanning may continue until the desired tanning level has been obtained. At this point, tissue that sticks out beyond the desired shape of the valve may be cut. But this should be done carefully; the final cut is only made after the heart valve has been fixed on a support structure.

At this point, the heart valve is ready to be positioned on a support structure. For reasons of clarity, the tissue is no longer hatched. Figures 3(a) and 3(b) show two possible embodiments of the heart valve (1 ) according to the invention. Figure 3(a) shows a heart valve (1 ) comprising three leaflets (2), a cylindrical base (3) and a bottom ring (4). If another mould is used, the resulting heart valve may look differently, as illustrated in figure 3(b). The cylindrical base (3) is much less pronounced and it does not have a bottom ring. Additionally in figure 3(b), the leaflets have already been separated through cuts (5). Both figures 3(a) and 3(b) refer to closed heart valves. Figure 3(c) illustrates an open valve (1 '), which may result from the previously described process. In figure 3(c), the cylindrical base (3') cannot be readily be distinguished from the leaflets (2'). The composition of open valve (1 ') comprising a cylindrical base (3') and leaflets (2') can more clearly be recognized in figure 5(d). Also the open valve according to the present invention has a continuous peripheral wall.

A support structure (20) is shown in figure 4. It comprises a bottom annular disc (21 ), a top annular disc (23) connected with each other through a cylindrical structure (22). In the case of a prosthetic heart valve device used as a replacement aortic valve, the bottom disc (21 ) may be regarded as the ventricular disc and the top disc (23) may be regarded as the aortic disc. The top disc (23) preferably comprises three legs (24) for supporting three leaflets of the heart valve. In order to be able to replace a heart valve percutaneously or by minimally invasive surgery (i.e. not through open heart surgery), the support structure has to be made collapsible. A preferred way of making the support structure collapsible is by making it from nitinol. The heart valve device in this case is self-expandable. Alternative collapsible support structures may also be used. Suitable means for expanding the valve device once it has been delivered in the appropriate position may then need to be provided.

Another possible support structure is shown in figure 4(b), which shows a schematic view of a balloon expandable stent. A self-expandable stent may also be used, such as shown in figure 4(c). Such alternative structures are well known in the art. The invention is not limited to any particular support structure. Instead the heart valve according to the present invention may be used with any suitable support structure. In a next step, to form a heart valve device ready for implant in the body, the support structure is placed over the heart valve. The legs (24) of the support structure are connected to the three leaflets (2), preferably though suturing or using mechanical means such as bendable piercing members, clips, or clamps. This has been shown, very schematically, in figure 5(a). The valve is also connected to the support along its bottom periphery. Non absorbable polyester may be used for suturing. In a next step, the leaflets (2) may be formed by cutting the tissue along the three dotted lines, indicated in figure 5(b). This way, the three leaflets (2) are formed. It is important to note that even though the legs may be sutured or otherwise attached to the support structure, the valve still has a continuous peripheral wall. As is also schematically indicated in figure 5(b), the remaining extra tissue is cut of along the bottom of the support. As was mentioned before, it is also possible that the three leaflets have already been formed by cutting in an earlier step.

For reasons of clarity, the tissue (12) is not shown as hatched in these figures. In figures 5(a) and 5(b), the tissue (12) that sticks out beyond its desired form has been left out, also for reasons of clarity. In figure 5(c), the top view of a heart valve device is shown and this extra tissue is shown. Part of this tissue may already have been removed in a previous step.

It is also foreseen that with an alternative design of the support structure the valve may be placed over the support structure (instead of the other way around). In this case, the support structure would still have three legs but would not have a top disc. The way of fixing the valve to the support structure is further similar to what was described before.

An open valve mounted on a similar support structure as shown in figures 5(a)-5(c) is shown in figure 5(d). The three leaflets 2' of the heart valve device are formed by the parts of the cylindrical valve which are not attached to the three legs (24) of the support structure. The material in between the legs will move inward and outward in use due to the prevailing pressure conditions. The cylindrical base (3') of the open valve is not visible, since it is covered by the support structure. Once the prosthetic heart valve device has been made available, it should be inspected to ensure it has the appropriate dimensions and it is well connected to the support structure. If the inspection results are positive, the device should be made sterile before it can be implanted in a patient's body. The sterilization may take place through a chemical process or through radiation. These techniques are well known in the art.

Claims

Claims
1. A method of making a prosthetic heart valve (1 ,1 ') comprising the steps of placing a piece of biological tissue (12) in or over a mould (10, 10'), and simultaneously tanning said tissue and forming it to an appropriate shape.
2. A method of making a prosthetic heart valve according to claim 1 , characterised in that the step of placing the biological tissue in or over a mould comprises using two moulds, a positive mould (10; 10') with substantially the desired shape of the valve and a negative mould (15; 15') with a negative shape of said positive mould (10; 10').
3. A method of making a prosthetic heart valve according to claim 2 and the step of placing the biological tissue in or over a mould comprises the steps of placing the tissue over said positive mould (10; 10') and then placing said negative mould (15; 15') over the biological tissue or comprises the steps of placing the biological tissue in said negative mould and then placing the positive mould within the negative mould.
4. A method of making a prosthetic heart valve according to any previous claim, characterised in that the mould has a bottom ring (11 ) and said step of placing said biological tissue in or over a mould includes folding the tissue around said bottom ring (11 ).
5. A method of making a prosthetic heart valve according to any previous claim, characterised in that said step of forming the tissue to an appropriate shape includes applying tension to the tissue.
6. A method of making a prosthetic heart valve according to any previous claim, including the additional step of cutting the biological tissue to form the leaflets (2; 2') of the valve.
7. A method of making a prosthetic heart valve according to any previous claim, characterised in that the prosthetic heart valve is a closed valve.
8. A method of making a prosthetic heart valve according to any of claims 1 -5, characterised in that the prosthetic heart valve is an open valve.
9. A method of making a prosthetic heart valve device comprising the steps of claim 1 and the additional step of attaching the prosthetic heart valve to a support structure (20).
10. A prosthetic heart valve (1 ) of a single piece of biological tissue
(12), said valve comprising a cylindrical base (3; 3') and leaflets (2; 2'), characterised in that said cylindrical base and leaflets have a continuous peripheral wall.
11. A prosthetic heart valve according to claim 10, characterised in that is a closed valve.
12. A prosthetic heart valve according to claim 10, characterised in that it is an open valve.
13. A prosthetic heart valve according to any of claims 10-12, characterised in that the heart valve is made by a method according to any of the claims 1 -6.
14. A prosthetic heart valve device comprising a prosthetic heart valve according to any of claims 10-13 and a support structure (20; 20'; 20") for supporting said valve.
15. A prosthetic heart valve device according to claim 14, characterised in that the support structure (20) comprises three legs (24) and the leaflets (2) of the valve are each connected to one of said legs.
16. A prosthetic heart valve device according to claim 14 or 15, characterised in that the support structure comprises two annular discs (21 ,23) for positioning the prosthetic heart valve in place, said two rings interconnected by a cylindrical structure (22).
17. A prosthetic heart valve device according to claim 14, characterised in that the support structure is a balloon expandable or a self- expandable stent.
18. A prosthetic heart valve device according to any of claims 14- 16, characterised in that the support structure is collapsible.
19. A prosthetic heart valve device according to claim 18, characterised in that, said support structure is made from nitinol.
20. A prosthetic heart valve device according to claim 18, characterised in that, said support structure is made from stainless steel or a cobalt chromium alloy.
21. A prosthetic heart valve device according to any of claims 14-
20, characterised in that it is a prosthetic aortic or pulmonary heart valve device.
22. A prosthetic heart valve device according to any of claims 14-
21 , characterised in that is a percutaneous heart valve device.
PCT/EP2009/057970 2008-06-26 2009-06-25 Prosthetic heart valve and method for making such a valve WO2009156471A1 (en)

Priority Applications (2)

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EP08159129 2008-06-26
EP08159129.9 2008-06-26

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103220999A (en) * 2011-09-09 2013-07-24 新干工业株式会社 Stent with valve, base material for forming stent with valve, and method for producing stent with valve
US8900294B2 (en) 2002-01-04 2014-12-02 Colibri Heart Valve Llc Method of controlled release of a percutaneous replacement heart valve
US9119738B2 (en) 2010-06-28 2015-09-01 Colibri Heart Valve Llc Method and apparatus for the endoluminal delivery of intravascular devices
EP3040053A4 (en) * 2013-08-30 2017-03-01 National Cerebral and Cardiovascular Center Base material for forming connective tissue structure and method for producing connective tissue structure
US9737400B2 (en) 2010-12-14 2017-08-22 Colibri Heart Valve Llc Percutaneously deliverable heart valve including folded membrane cusps with integral leaflets

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2046165A (en) * 1979-04-11 1980-11-12 Ross D N Shaping Biomaterial
US6129758A (en) * 1995-10-06 2000-10-10 Cardiomend Llc Products and methods for circulatory system valve repair
WO2001026587A1 (en) * 1999-10-14 2001-04-19 The International Heart Institute Of Montana Foundation Mold to form stent-less replacement heart valves from biological membranes
EP1671604A2 (en) * 1996-12-10 2006-06-21 Purdue Research Foundation Artificial vascular valves
WO2007046000A1 (en) * 2005-09-06 2007-04-26 Nanyang Technological University Valve mold and prosthesis for mammalian systems

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2046165A (en) * 1979-04-11 1980-11-12 Ross D N Shaping Biomaterial
US6129758A (en) * 1995-10-06 2000-10-10 Cardiomend Llc Products and methods for circulatory system valve repair
EP1671604A2 (en) * 1996-12-10 2006-06-21 Purdue Research Foundation Artificial vascular valves
WO2001026587A1 (en) * 1999-10-14 2001-04-19 The International Heart Institute Of Montana Foundation Mold to form stent-less replacement heart valves from biological membranes
WO2007046000A1 (en) * 2005-09-06 2007-04-26 Nanyang Technological University Valve mold and prosthesis for mammalian systems

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8900294B2 (en) 2002-01-04 2014-12-02 Colibri Heart Valve Llc Method of controlled release of a percutaneous replacement heart valve
US9125739B2 (en) 2002-01-04 2015-09-08 Colibri Heart Valve Llc Percutaneous replacement heart valve and a delivery and implantation system
US9186248B2 (en) 2002-01-04 2015-11-17 Colibri Heart Valve Llc Percutaneously implantable replacement heart valve device and method of making same
US9554898B2 (en) 2002-01-04 2017-01-31 Colibri Heart Valve Llc Percutaneous prosthetic heart valve
US9610158B2 (en) 2002-01-04 2017-04-04 Colibri Heart Valve Llc Percutaneously implantable replacement heart valve device and method of making same
US9119738B2 (en) 2010-06-28 2015-09-01 Colibri Heart Valve Llc Method and apparatus for the endoluminal delivery of intravascular devices
US9737400B2 (en) 2010-12-14 2017-08-22 Colibri Heart Valve Llc Percutaneously deliverable heart valve including folded membrane cusps with integral leaflets
CN103220999A (en) * 2011-09-09 2013-07-24 新干工业株式会社 Stent with valve, base material for forming stent with valve, and method for producing stent with valve
EP3040053A4 (en) * 2013-08-30 2017-03-01 National Cerebral and Cardiovascular Center Base material for forming connective tissue structure and method for producing connective tissue structure

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