CA2000500C - Flexible closing member, especially heart valve, and method of producing the same - Google Patents
Flexible closing member, especially heart valve, and method of producing the sameInfo
- Publication number
- CA2000500C CA2000500C CA 2000500 CA2000500A CA2000500C CA 2000500 C CA2000500 C CA 2000500C CA 2000500 CA2000500 CA 2000500 CA 2000500 A CA2000500 A CA 2000500A CA 2000500 C CA2000500 C CA 2000500C
- Authority
- CA
- Canada
- Prior art keywords
- closing element
- housing
- closing
- forming
- further defined
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
- B29C41/14—Dipping a core
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS 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
- A61F2/00—Filters 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
- A61F2/02—Prostheses implantable into the body
- A61F2/24—Heart 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; Valves implantable in the body
- A61F2/2412—Heart 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; Valves implantable in the body with soft flexible valve members, e.g. tissue valves shaped like natural valves
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
- B29C41/20—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles incorporating preformed parts or layers, e.g. moulding inserts or for coating articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
- B29C55/22—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of tubes
- B29C55/24—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of tubes radial
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/753—Medical equipment; Accessories therefor
- B29L2031/7532—Artificial members, protheses
- B29L2031/7534—Cardiovascular protheses
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S623/00—Prosthesis, i.e. artificial body members, parts thereof, or aids and accessories therefor
- Y10S623/90—Stent for heart valve
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/7722—Line condition change responsive valves
- Y10T137/7837—Direct response valves [i.e., check valve type]
- Y10T137/7879—Resilient material valve
Abstract
A method of producing flexible closing members, especially artificial heart valves, and a flexible closing member, especially an artificial heart valve, which can be produced according to such a method are described. According to the method of producing the housing of the closing member is radially expanded, the closing element of the closing member is formed as substantially plane two-dimensional element, and the plane two-dimensional element is connected to the housing in the expanded condition of the same. This method is preferably realized as dip method according to which the closing element is shaped and formed to the housing in a single working step. The described flexible closing member is an artificial three-sail heart valve which is characterized by a special shape of the three closing elements.
Description
Flexible closing member, especially heart valve, and method of producing the same The present invention concerns a method of producing flexible closing members, especially heart valves, which have a housing and at least one flexible sail-like closing element located within said housing and connected therewith, said closing element being movable to and fro between an open and a closed quasi-stable end position during which movement it changes its curvature, said method comprising the steps of shaping said closing element and simultaneously forming the same to the housing or connecting a pe-shaped closing element to said housing, especially forming to the same A method of the above-cited kind is known (seamless integration of polyurethane pocket valve sails into different valve ring geometries by M. Herold, B. Reck from research report 1983 - 84, Helmholtz Institut, RWTH
Aachen, pages 85 - 89). The method described in this publication serves for the manufacture of a heart valve having three sails. According to this method a pre-manufactured valve housing is mounted to a dip mould which has shaping surfaces for the closing elements, i.e.
sails, of the heart valve which have to be formed. These shaping surfaces have a two-dimensional curvature and predetermine the shape of the closing members in the closed condition of the heart valve. Thereafter, the dip mould with the pushed on valve housing is dipped into a polyurethane solution by which thin sheets of polyurethane are generated on the shaping surfaces which form the closing elements of the valve. These closing elements are simultaneously formed to the valve housing.
Thereafter, the dip mould is removed from the corresponding dip bath. Dependent on the desired thickness of the closing elements the dip process can be repeated several times. Finally, the dry sails which are still connected with one another are separated.
Thereafter, the valve can be released from the dip mould by simple pulling.
As mentioned above, according to this known method the closing elements are manufactured in the "closed condition" of the valve i.e. the shaping surfaces are curved in such a manner that the flexible polyurethane sheet forming on the shaping surfaces has a shape which is taken in by the several closing elements in the closed condition of the valve. Normally, this shape corresponds to the shape of a part-sphere, i.e. in any case to the shape of a double curved product. Such a shape with a two-dimensional curvature was especially selected on account of an improved stress distribution over the closing element in the closed condition of the same. As is well known, the sphere is an especially suited corpus here f or .
However, such a pre-formed sphere shape of the closing elements has the disadvantage that relatively high bulge pressures are necessary in order to convert the inwardly curved sphere shape into an outwardly curved sphere shape when the valve is opened. Furthermore, during this sail movement the danger is high that foldings of the material occur within the closing element. These foldings generate locally very high reversed bending stresses which result in early wearing. Additionally, these foldings and the insufficient flow guidance resulting therefrom are the origin for the occurrence of thrombosis and hemolysis reactions on account of the occurring increased shear stresses. Furthermore, it is assumed that hereby the tendency of calcification is increased either.
As mentioned above, with the heart valves produced by the method described-above, said valves being produced in the closed condition and corresponding pre-curvatures are incorporated into the closing elements, very high, three-dimensional restraining forces (bulge pressures) are necessary in order to convert the closing elements from their convex shape towards the direction of flow (closed condition) to their concave shape (opened condition). It is the object of the invention to provide a method of the cited kind with which a closing member can be manufactured which is characterized by an especially good opening and closing behaviour without any disturbing formation of folds and with which especially low pressures are sufficient in order to convert the closing elements from the closed condition into the opened condition and vice versa.
Furthermore, according to the invention a method is to be provided with which a closing member can be produced which is especially similar to the human aorta valve and which is thus especially suited for the implantation into the human heart. Such a closing member is to have especially good hemodynamics and durability.
According to the invention, the above-cited object is achieved with the above-described method by the following steps: radially expanding the housing, shaping the closing element as substantially plane two-dimensional element and simultaneously forming the same to the housing in the expanded condition of the same or connecting the closing element to the expanded housing, especially forming the same to the housing, wherein the housing is expanded such that the surface of the closing element enlarged with respect to the non-expanded condition enables the occupation of the two quasi-stable end positions by the closing element in the normal condition of the housing.
Accordingly, in opposition to the prior art, with the inventive method the closing element is not formed in the closed condition but in an intermediate condition between the closed and opened condition wherein the closing element is formed as substantially plane two-dimensional element. In order to achieve that this plane two-s dimensional element can take in not only the open but also the closed position, it is formed in the radially expanded condition of the housing of the closing member and is formed to the housing or, for the case that it is produced separately from the housing, it is formed such that it is adapted to the expanded shape of the housing whereafter it is connected to the expanded housing or is formed to the same. In this manner the closing element gets an enlarged surface which, in the normal condition of the housing, results in a curvature of the closing element radially inwardly or radially outwardly. This excessive surface of the closing element resulting from the special kind of shaping is dimensioned such that the closing element can take in the two quasi-stable end positions in the open and the closed condition when the housing is in its normal condition.
An alternative with respect to the above-cited method is described in patent claim 2.
According to the invention one intends to form the closing element as substantially plane two-dimensional element. However, also a two-dimensional element which is slightly simply curved in flow direction is suited.
This shape of the closing element is achieved by the formation thereof in a quasi-intermediate condition between the open and the closed condition. As mentioned above, the degree of the expansion or spreading of the housing and thus the enlargement of the surface of the closing is determined by the two end positions thereof.
By the above-described method of manufacturing it is achieved that the closing element can be converted from its closed position into its open position by change of its curvature without the application of large bulge pressures. The conversion between the two end positions is carried out by a quasi-two- dimensional rolling movement without any foldings and minimum bulge stresses.
Furthermore, in the open position the closing member utilizes the accompanying flow forces for a favourable closing step and thereby reduces the closing volumina.
Accordingly, the sail kinematics corresponds to that of natural heart valves in an excellent manner.
The shape-memory-effects occurring with conventional sail geometries which significantly contribute to the pressure loss and to the formation of membrane folds can be excluded with the inventive method. By this, on the one side the durability is increased and on the other side the losses of energy are reduced. The passage through this intermediate position (the condition of manufacturing) during each action of the heart is favourable with regard to the energetic conditions and flow conditions not only for the opening step but also for the closing step and results in an especially low stress of the sail material.
According to a preferred embodiment of the inventive method one utilizes the known dip method. Here, the closing element is formed in the greatest possible plane condition by a dip method with at least one dip process whereby the closing element is simultaneously formed to the housing which is then radially expanded.
According to an improvement of the inventive method the housing is expanded in flow direction. The expansion is carried out preferably with an opening angle of 2 - 20°.
For carrying out the expansion of the housing one utilizes the dip mould having the shape of a mandrel which was already used with the known dip method. As mentioned above, with the known method the housing was .. CA 02000500 1999-08-10 pushed onto the mandrel and arrested thereon whereafter the shaping process of the closing element was carried out. Now, according to the invention a mandrel is used which effects a radial expansion of the housing, especially a conical expansion of the same in flow direction. Furthermore, this mandrel differs from the mandrel used with the known method by the feature that the mandrel has a substantially plane shaping surface, possibly a shaping surface which is slightly curved in flow direction.
According to a special embodiment of the inventive method one produces a closing member (heart valve) having three closing elements by expanding a housing including three posts and by forming or connecting the closing elements (sails) to the hosing. Here, the housing is pushed onto the dip mould (mandrel) which conically tapers in flow direction wherein the posts of the housing are radially spreaded. Corresponding to the desired final layer thickness of the sails the mandrel which is prepared in such a manner is dipped into a corresponding plastics solution, especially polyurethane, for one or several times, pulled off and thereafter dried. After the true shaping process of the three closing elements the manufactured valve is cut corresponding to the line train of the free sail ends by means of a suitable method and is removed from the mandrel. Thereafter, the housing of the heart valve produced in such a manner deflects with the corresponding sails in the open (systolic) condition thereof. In this condition the housing has a circular cylindrical shape to which the closing element adapts itself, i.e. forms a part of a cylinder shell surface.
Suitable blood and tissue compatible plastics, especially polyurethane, are used as preferred manufacturing material for the closing elements.
_ 7 _ The housing provided with the closing element in this manner can be equipped thereafter with a suitable seam ring which enables an attachment to the corresponding tissue.
According to a special variant of the inventive method according to which one wishes to achieve a transition between the housing and the closing element which is as smooth as possible, one coats the mandrel of the dip mould at first with at least one first material layer by dipping, pushes the housing onto the dip mould and correspondingly expands the same and finally applies at least one second material layer by dipping. Than, one can turn up the corresponding layer and can bond or weld the same with the housing in an outer groove. The seam ring located over the outer groove covers the corresponding connection point.
It is a matter of course that the above-described inventive method is not suited alone for the manufacturing of heart valves. It is rather also suited for the manufacture of other closing members (valves), for instance for blood pumps. As mentioned above, for the manufacture preferably plastics are used, however, a manufacture is also possible with biologic tissue achieved by cultivation growing. Also the number of the closing elements can be variable. So, the method is especially suited for the manufacturing of closing members having one, two or three closing elements.
However, this does not exclude that also members can be produced having a number of closing elements exceeding this.
The closing members produced according to the inventive method have the further advantage that they close very well and open very far, i.e. have only a slight affect with regard to the flow conditions in their opened condition. So, for instance with a valve with a _ g _ cylindrical housing the flow opens the closing element nearly to the complete cylinder position so that laminar flow conditions without any turbulences are generated within the range of the opened closing element. These conditions can not be achieved by the predetermined two-dimensional curvature which is produced by the above-mentioned method according to the prior art.
A range of 50 - 800 Vim, especially of 100 - 300 Vim, is used as preferred material thickness for the closing element. With biologic material 600 - 800 ~m are preferred.
In addition to the above-mentioned dipping method the inventive method can be also realized by other plastics processing methods, as for instance by pressing, injection pressing, injection moulding, thermoforming and electrostatic flocking. However, the mentioned dipping method is preferred since it enables the shaping of the closing element and the forming thereof to the housing within one working step. If the closing element is separately produced, the connection of the same with the housing can be done by a thermal method or a bonding method. Here, the separately produced closing element has for instance the shape of a plane foil.
The closing elements (sails) can also be produced integrated with so-called bulbs (sinus valsalvae) similar to the natural aorta valves. Such a bulb valve can be used in artificial blood pumps or a conduit valve implant for the replacement of damaged aorta valves. The conduit can have only the shape of a cylindrical hose. The sails can also be directly integrated into an artificial blood pump without any bulbs.
Furthermore, the present invention is directed to a closing member, especially an artificial heart valve, comprising the features of the introductory portion of patent claim 22. Such heart valves are known (see the above-cited publication). They consist of two main members, the three flexible closing elements (sail membranes) which are offset with respect to one another for 120°, and the housing for the receipt of these closing elements (sail membranes). If the closing member is formed as artificial heart valve which is presupposed for the following specification, it has furthermore a seam ring which is necessary for the attachment of the heart valve to the tissue of the natural heart. The flexible closing elements can close the total flow section of the housing completely wherein the closing elements mutually support against one another.
Accordingly, the heart valve enables a blood flow through the heart in only one direction.
The problems connected with such closing members which are produced in the closed condition of the closing elements in such a manner that the closing elements get a corresponding curvature already during the shaping step have been already discussed in the beginning. During the movement of the closing elements from the closed condition into the open condition and vice versa foldings of the material occur in the closing element (membrane) which cause locally very high reversed bending stresses which result in early wearing. Furthermore, relatively high bulge pressures are necessary in order to let the closing elements carry out the desired snap movement.
According to the invention a closing member is to be provided with which during the movement of the closing elements especially low foldings of the material occur wherein the closing elements carry out the corresponding movement with especially low bulge pressures.
Accordingly, the inventive closing member is to have an especially good opening and closing behaviour without any disturbing formation of folds similar to the human aorta valve so that it is especially suited for the implantation into the human heart. Not only the hemodynamics but also the durability are to be improved.
According to the invention this object is achieved with a closing member of the cited kind having the characterizing features of patent claim 22.
Due to the inventive design of the closing elements the transition of the same between the two quasi-stable end positions (diastolic position and systolic position with a heart valve) is realized by a two-dimensional rolling movement which occurs without any formation of folds and with minimum necessary bulge pressures. If the closing member is formed as artificial heart valve, by this the function of the natural aorta valve is simulated in an especially exact manner.
In the open position the three closing elements form nearly cylindrically with bulgings at the respective posts of the housing. This open, quasi-stable position in which the total surface of the closing element is accessible from both sides (one-dimensionally curved) is especially suited for the realization of a surface modification in order to increase the biocompatibility.
Furthermore, the inventive construction guarantees a soft, undisturbed flow guidance in the open position and avoids thereby blood damaging high shear stresses generated by turbulences. In this position in which no impressed sphere shape etc. is present, as mentioned above, the relaxed closing elements can adapt to the flow, can generate a minimum flow resistance and can simulate the physiologic flow of the natural heart valve.
In the other quasi-stable position the closing elements close the flow section of the closing member nearly completely. The remaining opening area has the shape of a wave-like star with three rays in section. Due to the occurring pressure gradient the closing elements lay against one another in a really narrow or smooth manner.
Overlapping ranges occur which completely close the flow section thereafter.
The present housing posts which confine the several pockets are slightly inclined towards the center of the closing member in order to dampen the transmission of forces to the closing elements. The closing elements have the shape of a portion of the shell surface of a cylinder inclined with respect to the axis of the closing member. Exactly spoken, the closing elements have still a cylindrical portion in the range of their connecting lines with the housing in this position, the cylindrical portion changing continuously its curvature into the above-described cylinder shell part surface towards the center of the closing member. This includes a continuous transition of the shape of the closing element which is at first cylindrical towards the upper edge of a sail which is triangular towards the valve center. By this design one achieves an especially favourable support-bearing system for the reception of the pressure difference across the heart valve which is effective during the diastolis. The housing of the inventive closing member has preferably a shape which results from the section between a tube-like circular cylinder (housing) with a further circular cylinder which is inclined with respect to the closing member axis by a certain angle. The shape of the connection lines between the closing elements and the housing results in a corresponding manner.
Accordingly, the housing has three pockets which are confined by upwardly narrowing posts.
The inventive closing member is preferably manufactured by the above-mentioned method.
Improvements of the inventive closing member result from the subclaims.
In the following the invention is described by means of an embodiment in connection with the drawing in detail.
It is shown in figure 1 a dip mould used for practising the inventive method and on which a housing in an expanded condition is disposed;
figure 2 an inventive three-sail heart valve in its closed condition;
figure 3 the heart valve of figure 2 in its opened condition;
figure 4 a top view of the heart valve in its closed condition; and figure 5 a top view on the heart valve in its opened condition.
The dip mould (mandrel) 1 shown in figure 1 consists of a cylindrical portion 2 and a conical portion 3 which is triangularly formed in top view, as shown at 8.
Preferably, the dip mould consists of stainless steel on which the closing elements can be formed. Three mould surfaces 5 which are substantially plane (slightly curved towards the upper end of the dip mould) are located within the range of the conical portion 3.
For the manufacture of an artificial three-sail heart valve a pre-fabricated, substantially cylindrical valve housing 4 having three pockets for the reception of the corresponding closing elements is pushed onto the dip mould from the cylindrical end of the same. The housing .. CA 02000500 1999-08-10 is pushed so far until it seats on the conical portion 3 and is radially expanded thereby. The.border between the conical portion 3 and the cylindrical portion 2 is located approximately at the deepest point of the housing pockets.
Thereafter, the housing is adjusted in such a manner that its post 6 are seated on the corresponding support surfaces (between the mould surfaces) of the conical portion. In this condition the dip mould is dipped into a corresponding bath of a plastics solution once or several times wherein a flexible plastic foil forms on the mould surfaces 5, said plastic foil forming to the housing at the connection lines 7. After termination of the dipping process and a corresponding drying process the closing elements formed on the mould surfaces 5 are trimmed whereafter the final heart valve is removed from the dip mould. Then, the valve can be provided with a corresponding seam ring which is fastened within the groove 20 provided for this purpose.
A three-sail heart valve which has been preferably manufactured in accordance with the method described in connection with figure 1 is shown in figures 2 to 4.
Figure 2 shows the heart valve 10 consisting of a seam ring 14, three-sail like flexile closing elements 12 and a housing 11 in the closed condition of the closing elements while figure 3 shows the heart valve in the open condition of the closing elements. The housing 11 of the heart valve corresponds substantially to the housing described in connection with figure 1. The three closing elements are formed to the housing at the connection lines 15. As one can recognize with the closing elements shown in figure 2, these have substantially the form of a part of the shell surface of a circular cylinder inclined towards the axis of the closing member, when the closing elements are in their closed condition, wherein these parts, in the pressure-loaded condition, continuously ., CA 02000500 1999-08-10 change into a tapering rotational shape towards the center of the closing member. In this closed condition the three closing elements lay against one another with their upper edges, as shown at 21, so that the corresponding flow section is closed in this manner.
As one can take from figure 3, the closing elements 12 have in their opened condition substantially the shape of a cylinder shell part surface, i.e. the closing elements continue the cylinder curvature predetermined by the posts 13 of the housing. In this condition, the closing elements form approximately a continuation of the housing through which the three housing pockets are filled.
Figure 4 shows the heart valve of figures 2 and 3 in the closed condition of the closing elements. In the closed condition the closing elements lay against one another with their upper edges (at 21) wherein the upper edge of a closing element takes in the shape of the two legs of a triangle. Figure 5 shows the heart valve in the opened condition in top view.
Aachen, pages 85 - 89). The method described in this publication serves for the manufacture of a heart valve having three sails. According to this method a pre-manufactured valve housing is mounted to a dip mould which has shaping surfaces for the closing elements, i.e.
sails, of the heart valve which have to be formed. These shaping surfaces have a two-dimensional curvature and predetermine the shape of the closing members in the closed condition of the heart valve. Thereafter, the dip mould with the pushed on valve housing is dipped into a polyurethane solution by which thin sheets of polyurethane are generated on the shaping surfaces which form the closing elements of the valve. These closing elements are simultaneously formed to the valve housing.
Thereafter, the dip mould is removed from the corresponding dip bath. Dependent on the desired thickness of the closing elements the dip process can be repeated several times. Finally, the dry sails which are still connected with one another are separated.
Thereafter, the valve can be released from the dip mould by simple pulling.
As mentioned above, according to this known method the closing elements are manufactured in the "closed condition" of the valve i.e. the shaping surfaces are curved in such a manner that the flexible polyurethane sheet forming on the shaping surfaces has a shape which is taken in by the several closing elements in the closed condition of the valve. Normally, this shape corresponds to the shape of a part-sphere, i.e. in any case to the shape of a double curved product. Such a shape with a two-dimensional curvature was especially selected on account of an improved stress distribution over the closing element in the closed condition of the same. As is well known, the sphere is an especially suited corpus here f or .
However, such a pre-formed sphere shape of the closing elements has the disadvantage that relatively high bulge pressures are necessary in order to convert the inwardly curved sphere shape into an outwardly curved sphere shape when the valve is opened. Furthermore, during this sail movement the danger is high that foldings of the material occur within the closing element. These foldings generate locally very high reversed bending stresses which result in early wearing. Additionally, these foldings and the insufficient flow guidance resulting therefrom are the origin for the occurrence of thrombosis and hemolysis reactions on account of the occurring increased shear stresses. Furthermore, it is assumed that hereby the tendency of calcification is increased either.
As mentioned above, with the heart valves produced by the method described-above, said valves being produced in the closed condition and corresponding pre-curvatures are incorporated into the closing elements, very high, three-dimensional restraining forces (bulge pressures) are necessary in order to convert the closing elements from their convex shape towards the direction of flow (closed condition) to their concave shape (opened condition). It is the object of the invention to provide a method of the cited kind with which a closing member can be manufactured which is characterized by an especially good opening and closing behaviour without any disturbing formation of folds and with which especially low pressures are sufficient in order to convert the closing elements from the closed condition into the opened condition and vice versa.
Furthermore, according to the invention a method is to be provided with which a closing member can be produced which is especially similar to the human aorta valve and which is thus especially suited for the implantation into the human heart. Such a closing member is to have especially good hemodynamics and durability.
According to the invention, the above-cited object is achieved with the above-described method by the following steps: radially expanding the housing, shaping the closing element as substantially plane two-dimensional element and simultaneously forming the same to the housing in the expanded condition of the same or connecting the closing element to the expanded housing, especially forming the same to the housing, wherein the housing is expanded such that the surface of the closing element enlarged with respect to the non-expanded condition enables the occupation of the two quasi-stable end positions by the closing element in the normal condition of the housing.
Accordingly, in opposition to the prior art, with the inventive method the closing element is not formed in the closed condition but in an intermediate condition between the closed and opened condition wherein the closing element is formed as substantially plane two-dimensional element. In order to achieve that this plane two-s dimensional element can take in not only the open but also the closed position, it is formed in the radially expanded condition of the housing of the closing member and is formed to the housing or, for the case that it is produced separately from the housing, it is formed such that it is adapted to the expanded shape of the housing whereafter it is connected to the expanded housing or is formed to the same. In this manner the closing element gets an enlarged surface which, in the normal condition of the housing, results in a curvature of the closing element radially inwardly or radially outwardly. This excessive surface of the closing element resulting from the special kind of shaping is dimensioned such that the closing element can take in the two quasi-stable end positions in the open and the closed condition when the housing is in its normal condition.
An alternative with respect to the above-cited method is described in patent claim 2.
According to the invention one intends to form the closing element as substantially plane two-dimensional element. However, also a two-dimensional element which is slightly simply curved in flow direction is suited.
This shape of the closing element is achieved by the formation thereof in a quasi-intermediate condition between the open and the closed condition. As mentioned above, the degree of the expansion or spreading of the housing and thus the enlargement of the surface of the closing is determined by the two end positions thereof.
By the above-described method of manufacturing it is achieved that the closing element can be converted from its closed position into its open position by change of its curvature without the application of large bulge pressures. The conversion between the two end positions is carried out by a quasi-two- dimensional rolling movement without any foldings and minimum bulge stresses.
Furthermore, in the open position the closing member utilizes the accompanying flow forces for a favourable closing step and thereby reduces the closing volumina.
Accordingly, the sail kinematics corresponds to that of natural heart valves in an excellent manner.
The shape-memory-effects occurring with conventional sail geometries which significantly contribute to the pressure loss and to the formation of membrane folds can be excluded with the inventive method. By this, on the one side the durability is increased and on the other side the losses of energy are reduced. The passage through this intermediate position (the condition of manufacturing) during each action of the heart is favourable with regard to the energetic conditions and flow conditions not only for the opening step but also for the closing step and results in an especially low stress of the sail material.
According to a preferred embodiment of the inventive method one utilizes the known dip method. Here, the closing element is formed in the greatest possible plane condition by a dip method with at least one dip process whereby the closing element is simultaneously formed to the housing which is then radially expanded.
According to an improvement of the inventive method the housing is expanded in flow direction. The expansion is carried out preferably with an opening angle of 2 - 20°.
For carrying out the expansion of the housing one utilizes the dip mould having the shape of a mandrel which was already used with the known dip method. As mentioned above, with the known method the housing was .. CA 02000500 1999-08-10 pushed onto the mandrel and arrested thereon whereafter the shaping process of the closing element was carried out. Now, according to the invention a mandrel is used which effects a radial expansion of the housing, especially a conical expansion of the same in flow direction. Furthermore, this mandrel differs from the mandrel used with the known method by the feature that the mandrel has a substantially plane shaping surface, possibly a shaping surface which is slightly curved in flow direction.
According to a special embodiment of the inventive method one produces a closing member (heart valve) having three closing elements by expanding a housing including three posts and by forming or connecting the closing elements (sails) to the hosing. Here, the housing is pushed onto the dip mould (mandrel) which conically tapers in flow direction wherein the posts of the housing are radially spreaded. Corresponding to the desired final layer thickness of the sails the mandrel which is prepared in such a manner is dipped into a corresponding plastics solution, especially polyurethane, for one or several times, pulled off and thereafter dried. After the true shaping process of the three closing elements the manufactured valve is cut corresponding to the line train of the free sail ends by means of a suitable method and is removed from the mandrel. Thereafter, the housing of the heart valve produced in such a manner deflects with the corresponding sails in the open (systolic) condition thereof. In this condition the housing has a circular cylindrical shape to which the closing element adapts itself, i.e. forms a part of a cylinder shell surface.
Suitable blood and tissue compatible plastics, especially polyurethane, are used as preferred manufacturing material for the closing elements.
_ 7 _ The housing provided with the closing element in this manner can be equipped thereafter with a suitable seam ring which enables an attachment to the corresponding tissue.
According to a special variant of the inventive method according to which one wishes to achieve a transition between the housing and the closing element which is as smooth as possible, one coats the mandrel of the dip mould at first with at least one first material layer by dipping, pushes the housing onto the dip mould and correspondingly expands the same and finally applies at least one second material layer by dipping. Than, one can turn up the corresponding layer and can bond or weld the same with the housing in an outer groove. The seam ring located over the outer groove covers the corresponding connection point.
It is a matter of course that the above-described inventive method is not suited alone for the manufacturing of heart valves. It is rather also suited for the manufacture of other closing members (valves), for instance for blood pumps. As mentioned above, for the manufacture preferably plastics are used, however, a manufacture is also possible with biologic tissue achieved by cultivation growing. Also the number of the closing elements can be variable. So, the method is especially suited for the manufacturing of closing members having one, two or three closing elements.
However, this does not exclude that also members can be produced having a number of closing elements exceeding this.
The closing members produced according to the inventive method have the further advantage that they close very well and open very far, i.e. have only a slight affect with regard to the flow conditions in their opened condition. So, for instance with a valve with a _ g _ cylindrical housing the flow opens the closing element nearly to the complete cylinder position so that laminar flow conditions without any turbulences are generated within the range of the opened closing element. These conditions can not be achieved by the predetermined two-dimensional curvature which is produced by the above-mentioned method according to the prior art.
A range of 50 - 800 Vim, especially of 100 - 300 Vim, is used as preferred material thickness for the closing element. With biologic material 600 - 800 ~m are preferred.
In addition to the above-mentioned dipping method the inventive method can be also realized by other plastics processing methods, as for instance by pressing, injection pressing, injection moulding, thermoforming and electrostatic flocking. However, the mentioned dipping method is preferred since it enables the shaping of the closing element and the forming thereof to the housing within one working step. If the closing element is separately produced, the connection of the same with the housing can be done by a thermal method or a bonding method. Here, the separately produced closing element has for instance the shape of a plane foil.
The closing elements (sails) can also be produced integrated with so-called bulbs (sinus valsalvae) similar to the natural aorta valves. Such a bulb valve can be used in artificial blood pumps or a conduit valve implant for the replacement of damaged aorta valves. The conduit can have only the shape of a cylindrical hose. The sails can also be directly integrated into an artificial blood pump without any bulbs.
Furthermore, the present invention is directed to a closing member, especially an artificial heart valve, comprising the features of the introductory portion of patent claim 22. Such heart valves are known (see the above-cited publication). They consist of two main members, the three flexible closing elements (sail membranes) which are offset with respect to one another for 120°, and the housing for the receipt of these closing elements (sail membranes). If the closing member is formed as artificial heart valve which is presupposed for the following specification, it has furthermore a seam ring which is necessary for the attachment of the heart valve to the tissue of the natural heart. The flexible closing elements can close the total flow section of the housing completely wherein the closing elements mutually support against one another.
Accordingly, the heart valve enables a blood flow through the heart in only one direction.
The problems connected with such closing members which are produced in the closed condition of the closing elements in such a manner that the closing elements get a corresponding curvature already during the shaping step have been already discussed in the beginning. During the movement of the closing elements from the closed condition into the open condition and vice versa foldings of the material occur in the closing element (membrane) which cause locally very high reversed bending stresses which result in early wearing. Furthermore, relatively high bulge pressures are necessary in order to let the closing elements carry out the desired snap movement.
According to the invention a closing member is to be provided with which during the movement of the closing elements especially low foldings of the material occur wherein the closing elements carry out the corresponding movement with especially low bulge pressures.
Accordingly, the inventive closing member is to have an especially good opening and closing behaviour without any disturbing formation of folds similar to the human aorta valve so that it is especially suited for the implantation into the human heart. Not only the hemodynamics but also the durability are to be improved.
According to the invention this object is achieved with a closing member of the cited kind having the characterizing features of patent claim 22.
Due to the inventive design of the closing elements the transition of the same between the two quasi-stable end positions (diastolic position and systolic position with a heart valve) is realized by a two-dimensional rolling movement which occurs without any formation of folds and with minimum necessary bulge pressures. If the closing member is formed as artificial heart valve, by this the function of the natural aorta valve is simulated in an especially exact manner.
In the open position the three closing elements form nearly cylindrically with bulgings at the respective posts of the housing. This open, quasi-stable position in which the total surface of the closing element is accessible from both sides (one-dimensionally curved) is especially suited for the realization of a surface modification in order to increase the biocompatibility.
Furthermore, the inventive construction guarantees a soft, undisturbed flow guidance in the open position and avoids thereby blood damaging high shear stresses generated by turbulences. In this position in which no impressed sphere shape etc. is present, as mentioned above, the relaxed closing elements can adapt to the flow, can generate a minimum flow resistance and can simulate the physiologic flow of the natural heart valve.
In the other quasi-stable position the closing elements close the flow section of the closing member nearly completely. The remaining opening area has the shape of a wave-like star with three rays in section. Due to the occurring pressure gradient the closing elements lay against one another in a really narrow or smooth manner.
Overlapping ranges occur which completely close the flow section thereafter.
The present housing posts which confine the several pockets are slightly inclined towards the center of the closing member in order to dampen the transmission of forces to the closing elements. The closing elements have the shape of a portion of the shell surface of a cylinder inclined with respect to the axis of the closing member. Exactly spoken, the closing elements have still a cylindrical portion in the range of their connecting lines with the housing in this position, the cylindrical portion changing continuously its curvature into the above-described cylinder shell part surface towards the center of the closing member. This includes a continuous transition of the shape of the closing element which is at first cylindrical towards the upper edge of a sail which is triangular towards the valve center. By this design one achieves an especially favourable support-bearing system for the reception of the pressure difference across the heart valve which is effective during the diastolis. The housing of the inventive closing member has preferably a shape which results from the section between a tube-like circular cylinder (housing) with a further circular cylinder which is inclined with respect to the closing member axis by a certain angle. The shape of the connection lines between the closing elements and the housing results in a corresponding manner.
Accordingly, the housing has three pockets which are confined by upwardly narrowing posts.
The inventive closing member is preferably manufactured by the above-mentioned method.
Improvements of the inventive closing member result from the subclaims.
In the following the invention is described by means of an embodiment in connection with the drawing in detail.
It is shown in figure 1 a dip mould used for practising the inventive method and on which a housing in an expanded condition is disposed;
figure 2 an inventive three-sail heart valve in its closed condition;
figure 3 the heart valve of figure 2 in its opened condition;
figure 4 a top view of the heart valve in its closed condition; and figure 5 a top view on the heart valve in its opened condition.
The dip mould (mandrel) 1 shown in figure 1 consists of a cylindrical portion 2 and a conical portion 3 which is triangularly formed in top view, as shown at 8.
Preferably, the dip mould consists of stainless steel on which the closing elements can be formed. Three mould surfaces 5 which are substantially plane (slightly curved towards the upper end of the dip mould) are located within the range of the conical portion 3.
For the manufacture of an artificial three-sail heart valve a pre-fabricated, substantially cylindrical valve housing 4 having three pockets for the reception of the corresponding closing elements is pushed onto the dip mould from the cylindrical end of the same. The housing .. CA 02000500 1999-08-10 is pushed so far until it seats on the conical portion 3 and is radially expanded thereby. The.border between the conical portion 3 and the cylindrical portion 2 is located approximately at the deepest point of the housing pockets.
Thereafter, the housing is adjusted in such a manner that its post 6 are seated on the corresponding support surfaces (between the mould surfaces) of the conical portion. In this condition the dip mould is dipped into a corresponding bath of a plastics solution once or several times wherein a flexible plastic foil forms on the mould surfaces 5, said plastic foil forming to the housing at the connection lines 7. After termination of the dipping process and a corresponding drying process the closing elements formed on the mould surfaces 5 are trimmed whereafter the final heart valve is removed from the dip mould. Then, the valve can be provided with a corresponding seam ring which is fastened within the groove 20 provided for this purpose.
A three-sail heart valve which has been preferably manufactured in accordance with the method described in connection with figure 1 is shown in figures 2 to 4.
Figure 2 shows the heart valve 10 consisting of a seam ring 14, three-sail like flexile closing elements 12 and a housing 11 in the closed condition of the closing elements while figure 3 shows the heart valve in the open condition of the closing elements. The housing 11 of the heart valve corresponds substantially to the housing described in connection with figure 1. The three closing elements are formed to the housing at the connection lines 15. As one can recognize with the closing elements shown in figure 2, these have substantially the form of a part of the shell surface of a circular cylinder inclined towards the axis of the closing member, when the closing elements are in their closed condition, wherein these parts, in the pressure-loaded condition, continuously ., CA 02000500 1999-08-10 change into a tapering rotational shape towards the center of the closing member. In this closed condition the three closing elements lay against one another with their upper edges, as shown at 21, so that the corresponding flow section is closed in this manner.
As one can take from figure 3, the closing elements 12 have in their opened condition substantially the shape of a cylinder shell part surface, i.e. the closing elements continue the cylinder curvature predetermined by the posts 13 of the housing. In this condition, the closing elements form approximately a continuation of the housing through which the three housing pockets are filled.
Figure 4 shows the heart valve of figures 2 and 3 in the closed condition of the closing elements. In the closed condition the closing elements lay against one another with their upper edges (at 21) wherein the upper edge of a closing element takes in the shape of the two legs of a triangle. Figure 5 shows the heart valve in the opened condition in top view.
Claims (41)
1. A method of producing a closing member for controlling the flow of a fluid, said closing member having an annular housing through which the fluid flows and at least one closing element joined to the housing, said closing element being movable between an open quasi-stable end position in which fluid flow is permitted and a closed quasi-stable end position in which the closing element blocks the flow of fluid, said closing element being formed as a sail-like closing element the curvature of which changes during movement between the open and closed end positions, said method comprsiing the steps of:
circumferentially expanding the annular housing from a normal condition;
forming the closing element as a substantially two-dimensional element;
joining the closing element to the housing while the housing is in the expanded condition; and thereafter allowing the housing to circumferentially contract to the normal condition, whereby the joinder of the closing element to the housing while the latter is in the expanded condition enables the closing element to assume the two quasi-stable end positions when the housing is in its normal condition.
circumferentially expanding the annular housing from a normal condition;
forming the closing element as a substantially two-dimensional element;
joining the closing element to the housing while the housing is in the expanded condition; and thereafter allowing the housing to circumferentially contract to the normal condition, whereby the joinder of the closing element to the housing while the latter is in the expanded condition enables the closing element to assume the two quasi-stable end positions when the housing is in its normal condition.
2. A method of producing a closing member of controlling the flow of a fluid, said closing member having an annular housing through which the fluid flows and at least one closing element joined to the housing, said closing element being movable between an open quasi-stable end position in which fluid flow is permitted and a closed quasi-stable end position in which the closing element blocks the flow of fluid, said closing element being formed as a sail-like closing element, the curvature of which changes during movement between the open and closed end positions, said method comprising the steps of:
providing an annular housing, the circumference of which is greater than the circumference of the housing when in a normal condition;
forming the closing element as a substantially two-dimensional element;
joining the closing element to the housing while the housing has the greater circumference; and thereafter applying force to the housing to reduce the circumference of the housing to the normal condition, whereby the joinder of the closing element to the housing while the latter has the greater circumference enables the closing element to assume the two quasi-stable end positions when the housing is in it normal condition.
providing an annular housing, the circumference of which is greater than the circumference of the housing when in a normal condition;
forming the closing element as a substantially two-dimensional element;
joining the closing element to the housing while the housing has the greater circumference; and thereafter applying force to the housing to reduce the circumference of the housing to the normal condition, whereby the joinder of the closing element to the housing while the latter has the greater circumference enables the closing element to assume the two quasi-stable end positions when the housing is in it normal condition.
3. A method according to claim 1 wherein the step of forming the closing element is further defined as forming the closing element to have a minimum surface area, the mean curvature at each point of the surface being zero.
4. A method according to claim 2 wherein the step of forming the closing element is further defined as forming the closing element to have a minimum surface area, the means curvature at each point of the surface being zero.
5. A method according to claim 1 further defined as a method of producing a closing member for controlling a fluid flowing in one direction through the housing, said method being further defined as forming the closing element to have a curve along the flow direction.
6. A method according to claim 2 further defined as a method of producing a closing member for controlling a fluid flowing in one direction through the housing, said method being further defined as forming the closing element to have a curve along the flow direction.
7. A method according to claim 1 wherein the step of forming the closing element is further defined as dipping the housing in a material used to comprise the closing element, whereby the closing element is simultaneously joined to the housing.
8. A method according to claim 1 further defined as a method of producing a closing member in which the fluid flows in one direction through the housing and wherein the step of circumferentially expanding the annular housing is further defined as conically expanding the housing in the flow direction.
9. A method according to claim 8 wherein the step of circumferentially expanding the annular housing is further defined as conically expanding the housing as the frustum of a cone having an apex angle of 2°-20°.
10. A method according to claim 1 wherein the step of circumferentially expanding the annular housing is further defined as circumferentially expanding the annular housing by placing the housing on a mandrel, and wherein the step of forming the closing element is further defined as forming the closing element on a shaping surface of the mandrel.
11. A method according to claim 8 wherein the step of circumferentially expanding the annular housing is further defined as circumferentially expanding the annular housing by placing the housing on a mandrel, and wherein the step of forming the closing element is further defined as forming the closing element on a shaping surface of the mandrel.
12. A method according to claim 3 wherein the step of forming the closing element is further defined as forming the closing element on a mandrel having a substantially plane shaping surface.
13. A method according to claim 5 wherein the step of forming the closing element is further defined as forming the closing element on a mandrel having a shaping surface for the closing element which is curved in the flow direction.
14. A method according to claim 8 wherein the step of circumferentially expanding the annular housing is further defined as placing the housing on a conically shaped mandrel.
15. A method according to claim 1 further defined as forming the closing element from a flexible, biocompatible plastic.
16. A method according to claim 2 further defined as forming the closing element from a flexible, biocompatible plastic.
17. A method according to claim 10 further defined as including the step of dipping the mandrel in a material used to comprise the closing element to coat the mandrel;
placing the housing on the coated mandrel to circumferentially expand the annular housing; and dipping the mandrel and housing in the closing element material to form the closing element on the shaping surface of the mandrel.
placing the housing on the coated mandrel to circumferentially expand the annular housing; and dipping the mandrel and housing in the closing element material to form the closing element on the shaping surface of the mandrel.
18. A method according to claim 1 further defined as including the step of providing a housing having an annular base and having a plurality of circumferentially spaced posts extending axially away from the base generally parallel to the flow direction and as including the step of joining a plurality of closing elements to the base and posts.
19. A method according to claim 2 further defined as including the step of providing a housing having an annular base and having a plurality of circumferentially spaced posts extending axially away from the base generally parallel to the flow direction and as including the step of joining a plurality of closing elements to the base and posts.
20. A method according to claim 1 further defined as joining the closing element to the housing by one of a thermal welding process and a bonding process.
21. A method according to claim 2 further defined as joining the closing element to the housing by one of a thermal welding process and a bonding process.
22. A method according to claim 1 wherein the step of forming the closing element is further defined as forming the closing element from a biological tissue.
23. A method according to claim 2 wherein the step of forming the closing element is further defined as forming the closing element from a biological tissue.
24. A method according to claim 1 wherein the step of forming the closing element is further defined as forming the closing element to have a precurvature when in its open and closed positions.
25. A method according to claim 24 wherein the step of forming the closing element is further defined as forming the closing element to have a free end and as forming the precurvature of the closing element such that the mean curvature H of the surface of the closing element and of the free end thereof is in a relation to the closing element inner diameter d of between -0.6<Hd/2<0.6, and wherein the curved train of the free edge of the closing element is between -0.3 and +0.3.
26. A method according to claim 2 wherein the step of forming the closing element is further defined as forming the closing element to have a precurvature when in its open and closed positions.
27. A method according to claim 5 wherein the step of forming the closing element is further defined as forming the closing element to have a free end and as forming the precurvature of the closing element such that the mean curvature H of the surface of the closing element and of the free end thereof is in a relation to the closing element inner diameter d of between -0.6<Hd/2<0.6, and wherein the curved train of the free end of the closing element is between -0.3 and +0.3.
28. A method according to claim 1 further defined as a method of producing an artificial heart valve.
29. A method according to claim 2 further defined as a method of producing an artificial heart valve.
30. A method according to claim 28 wherein the step of forming the closing element is further defined as forming the closing element integrally with bulbs resembling those found in a natural aortic valve.
31. A method according to claim 1 further defined as integrating the closing element into a blood pump.
32. A method according to claim 2 further defined as integrating the closing element into a blood pump.
33. A method of producing an artificial heart valve for controlling the flow of blood, said artificial heart valve having an annular housing through which the blood flows in a flow direction, said artificial heart valve having a plurality of closing elements joined to the housing, said closing elements being movable between an open quasi-stable end position in which blood flow is permitted and a closed quasi-stable end position in which the closing elements block the flow of blood, said closing elements being formed as sail-like closing elements, the curvature of which changes during movement between the open and closed end positions, said method comprising the steps of:
providing an annular housing for the heart valve having a base and a plurality of circumferentially spaced posts extending from the base in the flow direction;
placing the housing on a mandrel for circumferentially expanding the annular housing from a normal condition;
dipping the mandrel and housing in a polyethylene material to form the closing elements as substantially two-dimensional elements on shaping surfaces provided on the mandrel and to join the closing elements to the housing while the housing is in the expanded condition;
and thereafter removing the housing and closing elements from the mandrel to allow the housing to circumferentially contract to the normal condition, whereby the joinder of the closing elements to the housing while the latter is in the expanded condition enables the closing elements to assume the two quasi-stable end positions when the housing is in its normal condition.
providing an annular housing for the heart valve having a base and a plurality of circumferentially spaced posts extending from the base in the flow direction;
placing the housing on a mandrel for circumferentially expanding the annular housing from a normal condition;
dipping the mandrel and housing in a polyethylene material to form the closing elements as substantially two-dimensional elements on shaping surfaces provided on the mandrel and to join the closing elements to the housing while the housing is in the expanded condition;
and thereafter removing the housing and closing elements from the mandrel to allow the housing to circumferentially contract to the normal condition, whereby the joinder of the closing elements to the housing while the latter is in the expanded condition enables the closing elements to assume the two quasi-stable end positions when the housing is in its normal condition.
34. A valve member, adapted for use as a heart valve, said valve member permitting fluid to pass therethrough in a flow direction of the valve member responsive to pulsatile pressure urging such flow, said valve blocking fluid flow therethrough in a counter-flow direction responsive to incipient fluid flow in the counter-flow direction, said valve member comprising:
a body element having a base ring portion through which the fluid flows, said body element having a plurality of posts mounted on said base ring portion at circumferentially spaced locations about the base ring portion, said posts extending from said base ring portion in a direction parallel to an axis of said base ring portion, and having terminal ends, said body element being capable of assuming a condition in which it is circumferentially expanded and a condition in which it is circumferentially contracted, in which latter condition the valve member is used; and closure means having flexible membranes mounted on said base ring portion and between pairs of circumferentially adjacent posts, said membranes being formed solely of a thin, non-reinforced, film-like material having a predetermined thickness, each of said membranes being formed, when said base ring portion is in the expanded condition, as a generally planar sheet lying generally in a chord-like plane extending between adjacent posts and being rendered flaccid when said ring is subsequently placed in the contracted condition, said membranes having edges extending between said ends of said posts, said membranes being placed, responsive to the pulsatile pressure, in a generally cylindrical, open position in which fluid flows through the valve member in the flow direction, said non-reinforced membranes maintaining themselves in said open position upon the removal of the pulsatile pressure due to their flaccid nature and original planar form and as a result of the absence of circumferential tension in the membranes other than that produced by the fluid flow, said closure membranes being placed, responsive to the incipient fluid flow int h3e counter-flow direction, in a generally concave closed position in which the edges of the membranes re contiguous to block fluid flow through the valve member, said membranes remaining in said closed position in the absence of the application of the pulsatile pressure thereto.
a body element having a base ring portion through which the fluid flows, said body element having a plurality of posts mounted on said base ring portion at circumferentially spaced locations about the base ring portion, said posts extending from said base ring portion in a direction parallel to an axis of said base ring portion, and having terminal ends, said body element being capable of assuming a condition in which it is circumferentially expanded and a condition in which it is circumferentially contracted, in which latter condition the valve member is used; and closure means having flexible membranes mounted on said base ring portion and between pairs of circumferentially adjacent posts, said membranes being formed solely of a thin, non-reinforced, film-like material having a predetermined thickness, each of said membranes being formed, when said base ring portion is in the expanded condition, as a generally planar sheet lying generally in a chord-like plane extending between adjacent posts and being rendered flaccid when said ring is subsequently placed in the contracted condition, said membranes having edges extending between said ends of said posts, said membranes being placed, responsive to the pulsatile pressure, in a generally cylindrical, open position in which fluid flows through the valve member in the flow direction, said non-reinforced membranes maintaining themselves in said open position upon the removal of the pulsatile pressure due to their flaccid nature and original planar form and as a result of the absence of circumferential tension in the membranes other than that produced by the fluid flow, said closure membranes being placed, responsive to the incipient fluid flow int h3e counter-flow direction, in a generally concave closed position in which the edges of the membranes re contiguous to block fluid flow through the valve member, said membranes remaining in said closed position in the absence of the application of the pulsatile pressure thereto.
35. A valve member according to claim 34 wherein the thickness of said thin, film-like material forming said membranes is between substantially 50 µm and substantially 800 µm.
36. A valve member according to claim 35 wherein the thickness of said thin, film-like material forming said membranes is between substantially 100 µm and substantially 300 µm.
37. A valve member according to claim 34 wherein each of said membranes in the closed position has a generally triangular shaped transition portion immediately adjacent said edge and a partially cylindrical surface adjacent said base ring portion and embraced by said posts.
38. A valve member according to claim 34 wherein said circumferentially adjacent posts form curved cut-out portions therebetween spanned by said membranes.
39. A valve member according to claim 38 wherein said membranes are connected to said base ring portion and said posts at outer surfaces of said base ring portion and posts.
40. A valve member according to claim 38 wherein said membranes are connected to said base ring portion and said posts intermediate the outer and inner surfaces of said base ring portion and posts.
41. A valve member according to claim 38 wherein said body element is tapered along the axis of said base ring portion in the flow direction of said valve member.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3834545.5 | 1988-10-11 | ||
| DE19883834545 DE3834545A1 (en) | 1988-10-11 | 1988-10-11 | FLEXIBLE LOCKING ORGAN, PARTICULARLY HEART VALVE, AND METHOD FOR PRODUCING THE SAME |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2000500A1 CA2000500A1 (en) | 1990-04-11 |
| CA2000500C true CA2000500C (en) | 1999-11-16 |
Family
ID=6364836
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2000500 Expired - Fee Related CA2000500C (en) | 1988-10-11 | 1989-10-11 | Flexible closing member, especially heart valve, and method of producing the same |
Country Status (6)
| Country | Link |
|---|---|
| US (2) | US5116564A (en) |
| EP (1) | EP0363753B1 (en) |
| JP (1) | JP2990363B2 (en) |
| CA (1) | CA2000500C (en) |
| DE (1) | DE3834545A1 (en) |
| ES (1) | ES2076183T3 (en) |
Families Citing this family (127)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5609626A (en) * | 1989-05-31 | 1997-03-11 | Baxter International Inc. | Stent devices and support/restrictor assemblies for use in conjunction with prosthetic vascular grafts |
| US5037434A (en) * | 1990-04-11 | 1991-08-06 | Carbomedics, Inc. | Bioprosthetic heart valve with elastic commissures |
| DK124690D0 (en) * | 1990-05-18 | 1990-05-18 | Henning Rud Andersen | FAT PROTECTION FOR IMPLEMENTATION IN THE BODY FOR REPLACEMENT OF NATURAL FLEET AND CATS FOR USE IN IMPLEMENTING A SUCH FAT PROTECTION |
| JPH04300474A (en) * | 1991-03-27 | 1992-10-23 | Fuji Kobunshi Kogyo Kk | Rubber check valve |
| DE4222610A1 (en) * | 1992-07-10 | 1994-01-13 | Jansen Josef Dr Ing | Support housing for flap and closing elements |
| US5931969A (en) | 1994-07-29 | 1999-08-03 | Baxter International Inc. | Methods and apparatuses for treating biological tissue to mitigate calcification |
| USRE40570E1 (en) | 1994-07-29 | 2008-11-11 | Edwards Lifesciences Corporation | Apparatuses and methods for treating biological tissue to mitigate calcification |
| US5549666A (en) * | 1994-09-02 | 1996-08-27 | Baxter International Inc. | Natural tissue valve prostheses having variably complaint leaflets |
| US5716399A (en) * | 1995-10-06 | 1998-02-10 | Cardiomend Llc | Methods of heart valve repair |
| EP0808614B1 (en) * | 1996-05-23 | 2003-02-26 | Samsung Electronics Co., Ltd. | Flexible self-expandable stent and method for making the same |
| DE19624948A1 (en) * | 1996-06-24 | 1998-01-02 | Adiam Medizintechnik Gmbh & Co | Prosthetic heart valve |
| GB2324729B (en) | 1997-04-30 | 2002-01-02 | Bradford Hospitals Nhs Trust | Lung treatment device |
| US5954766A (en) | 1997-09-16 | 1999-09-21 | Zadno-Azizi; Gholam-Reza | Body fluid flow control device |
| US6889082B2 (en) * | 1997-10-09 | 2005-05-03 | Orqis Medical Corporation | Implantable heart assist system and method of applying same |
| US6390969B1 (en) | 1997-10-09 | 2002-05-21 | Orqis Medical Corporation | Implantable heart assist system and method of applying same |
| US6610004B2 (en) | 1997-10-09 | 2003-08-26 | Orqis Medical Corporation | Implantable heart assist system and method of applying same |
| US6387037B1 (en) | 1997-10-09 | 2002-05-14 | Orqis Medical Corporation | Implantable heart assist system and method of applying same |
| UA56262C2 (en) | 1997-10-09 | 2003-05-15 | Орквіс Медікел Корпорейшн | Extracardiac pumping system for supplementing blood circulation |
| DE19755738A1 (en) * | 1997-12-16 | 1999-07-15 | Adiam Medizintechnik Gmbh & Co | Process for separating and / or removing processing of prefabricated plastic films |
| NL1008349C2 (en) * | 1998-02-19 | 1999-08-20 | Univ Eindhoven Tech | Mandrel for making stented or stentless heart valve comprising a fibre reinforced composite material |
| WO1999062431A1 (en) | 1998-06-02 | 1999-12-09 | Cook Incorporated | Multiple-sided intraluminal medical device |
| US7452371B2 (en) * | 1999-06-02 | 2008-11-18 | Cook Incorporated | Implantable vascular device |
| US6117169A (en) * | 1998-06-24 | 2000-09-12 | Sulzer Carbomedics Inc. | Living hinge attachment of leaflet to a valve body |
| US6214054B1 (en) * | 1998-09-21 | 2001-04-10 | Edwards Lifesciences Corporation | Method for fixation of biological tissues having mitigated propensity for post-implantation calcification and thrombosis and bioprosthetic devices prepared thereby |
| US6475239B1 (en) | 1998-10-13 | 2002-11-05 | Sulzer Carbomedics Inc. | Method for making polymer heart valves with leaflets having uncut free edges |
| US6319281B1 (en) * | 1999-03-22 | 2001-11-20 | Kumar R. Patel | Artificial venous valve and sizing catheter |
| US6283995B1 (en) | 1999-04-15 | 2001-09-04 | Sulzer Carbomedics Inc. | Heart valve leaflet with scalloped free margin |
| US6666885B2 (en) | 1999-04-16 | 2003-12-23 | Carbomedics Inc. | Heart valve leaflet |
| US6283994B1 (en) | 1999-04-16 | 2001-09-04 | Sulzer Carbomedics Inc. | Heart valve leaflet |
| US6174331B1 (en) | 1999-07-19 | 2001-01-16 | Sulzer Carbomedics Inc. | Heart valve leaflet with reinforced free margin |
| DE69942954D1 (en) * | 1999-09-10 | 2010-12-30 | Cook Inc | ENDOVASCULAR TREATMENT OF CHRONIC VENOUS INSUFFICIENCY |
| US20030097175A1 (en) * | 1999-12-08 | 2003-05-22 | O'connor Bernard | Heart valve prosthesis and method of manufacture |
| GB0114345D0 (en) | 2001-06-13 | 2001-08-08 | Aortech Europ Ltd | Heart valve prosthesis and method of manufacture |
| GB9928905D0 (en) | 1999-12-08 | 2000-02-02 | Aortech Europ Ltd | Prosthesis |
| DE60127530T2 (en) * | 2000-02-03 | 2007-12-13 | Cook Inc., Bloomington | IMPLANTABLE VASCULAR DEVICE |
| US20050267560A1 (en) * | 2000-02-03 | 2005-12-01 | Cook Incorporated | Implantable bioabsorbable valve support frame |
| JP4383707B2 (en) * | 2000-03-03 | 2009-12-16 | パトリシア・イー・ソープ | Spherical valve and stent for treating vascular reflux |
| US6679264B1 (en) * | 2000-03-04 | 2004-01-20 | Emphasys Medical, Inc. | Methods and devices for use in performing pulmonary procedures |
| US20030070683A1 (en) | 2000-03-04 | 2003-04-17 | Deem Mark E. | Methods and devices for use in performing pulmonary procedures |
| US8474460B2 (en) * | 2000-03-04 | 2013-07-02 | Pulmonx Corporation | Implanted bronchial isolation devices and methods |
| DE10050099A1 (en) * | 2000-10-09 | 2002-04-18 | Adiam Life Science Ag | Tubular cardiac valve prosthesis has individual parts all made of polyurethane, forming an integrated component |
| US6953332B1 (en) * | 2000-11-28 | 2005-10-11 | St. Jude Medical, Inc. | Mandrel for use in forming valved prostheses having polymer leaflets by dip coating |
| US20020112729A1 (en) * | 2001-02-21 | 2002-08-22 | Spiration, Inc. | Intra-bronchial obstructing device that controls biological interaction with the patient |
| US20040074491A1 (en) * | 2001-03-02 | 2004-04-22 | Michael Hendricksen | Delivery methods and devices for implantable bronchial isolation devices |
| US7798147B2 (en) * | 2001-03-02 | 2010-09-21 | Pulmonx Corporation | Bronchial flow control devices with membrane seal |
| US7011094B2 (en) * | 2001-03-02 | 2006-03-14 | Emphasys Medical, Inc. | Bronchial flow control devices and methods of use |
| US20030050648A1 (en) * | 2001-09-11 | 2003-03-13 | Spiration, Inc. | Removable lung reduction devices, systems, and methods |
| US6562069B2 (en) | 2001-09-19 | 2003-05-13 | St. Jude Medical, Inc. | Polymer leaflet designs for medical devices |
| WO2003030975A2 (en) * | 2001-10-11 | 2003-04-17 | Emphasys Medical, Inc. | Bronchial flow control devices and methods of use |
| US6592594B2 (en) * | 2001-10-25 | 2003-07-15 | Spiration, Inc. | Bronchial obstruction device deployment system and method |
| US6878168B2 (en) | 2002-01-03 | 2005-04-12 | Edwards Lifesciences Corporation | Treatment of bioprosthetic tissues to mitigate post implantation calcification |
| US20060235432A1 (en) * | 2002-02-21 | 2006-10-19 | Devore Lauri J | Intra-bronchial obstructing device that controls biological interaction with the patient |
| US6929637B2 (en) * | 2002-02-21 | 2005-08-16 | Spiration, Inc. | Device and method for intra-bronchial provision of a therapeutic agent |
| US20030154988A1 (en) * | 2002-02-21 | 2003-08-21 | Spiration, Inc. | Intra-bronchial device that provides a medicant intra-bronchially to the patient |
| AU2003220124A1 (en) * | 2002-03-08 | 2003-09-22 | Emphasys Medical, Inc. | Methods and devices for inducing collapse in lung regions fed by collateral pathways |
| US20030216769A1 (en) * | 2002-05-17 | 2003-11-20 | Dillard David H. | Removable anchored lung volume reduction devices and methods |
| US20030181922A1 (en) | 2002-03-20 | 2003-09-25 | Spiration, Inc. | Removable anchored lung volume reduction devices and methods |
| US20030195385A1 (en) * | 2002-04-16 | 2003-10-16 | Spiration, Inc. | Removable anchored lung volume reduction devices and methods |
| FR2838631B1 (en) * | 2002-04-23 | 2004-12-24 | Engeneering And Technological | METHOD FOR PRODUCING AN AORTIC OR MITRAL HEART VALVE PROSTHESIS AND AORTIC OR MITRAL HEART VALVE PROSTHESIS THUS OBTAINED |
| US20030212412A1 (en) * | 2002-05-09 | 2003-11-13 | Spiration, Inc. | Intra-bronchial obstructing device that permits mucus transport |
| US7828839B2 (en) * | 2002-05-16 | 2010-11-09 | Cook Incorporated | Flexible barb for anchoring a prosthesis |
| US20040117004A1 (en) * | 2002-05-16 | 2004-06-17 | Osborne Thomas A. | Stent and method of forming a stent with integral barbs |
| US20040039250A1 (en) * | 2002-05-28 | 2004-02-26 | David Tholfsen | Guidewire delivery of implantable bronchial isolation devices in accordance with lung treatment |
| US20040010209A1 (en) * | 2002-07-15 | 2004-01-15 | Spiration, Inc. | Device and method for measuring the diameter of an air passageway |
| US20040059263A1 (en) * | 2002-09-24 | 2004-03-25 | Spiration, Inc. | Device and method for measuring the diameter of an air passageway |
| AU2003256798A1 (en) * | 2002-07-26 | 2004-02-16 | Emphasys Medical, Inc. | Bronchial flow control devices with membrane seal |
| DE10237787A1 (en) * | 2002-08-17 | 2004-03-04 | Robert Bosch Gmbh | Layer system with a silicon layer and a passivation layer, method for producing a passivation layer on a silicon layer and their use |
| AU2003293116A1 (en) * | 2002-11-27 | 2004-06-23 | Emphasys Medical, Inc. | Delivery method and device for implantable bronchial isolation devices |
| US7814912B2 (en) * | 2002-11-27 | 2010-10-19 | Pulmonx Corporation | Delivery methods and devices for implantable bronchial isolation devices |
| US20040210248A1 (en) * | 2003-03-12 | 2004-10-21 | Spiration, Inc. | Apparatus, method and assembly for delivery of intra-bronchial devices |
| WO2004082536A1 (en) * | 2003-03-20 | 2004-09-30 | Aortech International Plc | Valve |
| US7100616B2 (en) * | 2003-04-08 | 2006-09-05 | Spiration, Inc. | Bronchoscopic lung volume reduction method |
| US7200559B2 (en) * | 2003-05-29 | 2007-04-03 | Microsoft Corporation | Semantic object synchronous understanding implemented with speech application language tags |
| US7533671B2 (en) * | 2003-08-08 | 2009-05-19 | Spiration, Inc. | Bronchoscopic repair of air leaks in a lung |
| US20050085683A1 (en) * | 2003-10-15 | 2005-04-21 | Bolling Steven F. | Implantable heart assist system and method of applying same |
| US20050131385A1 (en) * | 2003-12-12 | 2005-06-16 | Bolling Steven F. | Cannulae for selectively enhancing blood flow |
| US20050178389A1 (en) * | 2004-01-27 | 2005-08-18 | Shaw David P. | Disease indications for selective endobronchial lung region isolation |
| US8337545B2 (en) | 2004-02-09 | 2012-12-25 | Cook Medical Technologies Llc | Woven implantable device |
| US8206684B2 (en) * | 2004-02-27 | 2012-06-26 | Pulmonx Corporation | Methods and devices for blocking flow through collateral pathways in the lung |
| EP1722716B1 (en) * | 2004-03-08 | 2017-08-16 | Pulmonx, Inc | Implanted bronchial isolation devices and methods |
| US8216299B2 (en) | 2004-04-01 | 2012-07-10 | Cook Medical Technologies Llc | Method to retract a body vessel wall with remodelable material |
| US7637937B2 (en) | 2004-04-08 | 2009-12-29 | Cook Incorporated | Implantable medical device with optimized shape |
| US20060122686A1 (en) * | 2004-05-10 | 2006-06-08 | Ran Gilad | Stent and method of manufacturing same |
| US20060122693A1 (en) * | 2004-05-10 | 2006-06-08 | Youssef Biadillah | Stent valve and method of manufacturing same |
| US20060122692A1 (en) * | 2004-05-10 | 2006-06-08 | Ran Gilad | Stent valve and method of using same |
| US7445592B2 (en) * | 2004-06-10 | 2008-11-04 | Orqis Medical Corporation | Cannulae having reduced flow resistance |
| US20060030863A1 (en) * | 2004-07-21 | 2006-02-09 | Fields Antony J | Implanted bronchial isolation device delivery devices and methods |
| US7771472B2 (en) * | 2004-11-19 | 2010-08-10 | Pulmonx Corporation | Bronchial flow control devices and methods of use |
| US20060184199A1 (en) * | 2005-02-14 | 2006-08-17 | O'leary Shawn | Apparatus and methods for reducing bleeding from a cannulation site |
| US8876791B2 (en) | 2005-02-25 | 2014-11-04 | Pulmonx Corporation | Collateral pathway treatment using agent entrained by aspiration flow current |
| US20060224110A1 (en) * | 2005-03-17 | 2006-10-05 | Scott Michael J | Methods for minimally invasive vascular access |
| US7579381B2 (en) * | 2005-03-25 | 2009-08-25 | Edwards Lifesciences Corporation | Treatment of bioprosthetic tissues to mitigate post implantation calcification |
| US8197534B2 (en) * | 2005-03-31 | 2012-06-12 | Cook Medical Technologies Llc | Valve device with inflatable chamber |
| JP4735111B2 (en) * | 2005-08-03 | 2011-07-27 | 独立行政法人国立循環器病研究センター | Stent with artificial valve |
| JP2007037764A (en) * | 2005-08-03 | 2007-02-15 | National Cardiovascular Center | Prosthetic valve |
| JP4815936B2 (en) * | 2005-08-03 | 2011-11-16 | 独立行政法人国立循環器病研究センター | Artificial blood vessel having an artificial valve, manufacturing method thereof, and artificial blood vessel manufacturing material |
| US7691151B2 (en) | 2006-03-31 | 2010-04-06 | Spiration, Inc. | Articulable Anchor |
| US7829986B2 (en) * | 2006-04-01 | 2010-11-09 | Stats Chippac Ltd. | Integrated circuit package system with net spacer |
| EP2077718B2 (en) | 2006-10-27 | 2022-03-09 | Edwards Lifesciences Corporation | Biological tissue for surgical implantation |
| US9101691B2 (en) | 2007-06-11 | 2015-08-11 | Edwards Lifesciences Corporation | Methods for pre-stressing and capping bioprosthetic tissue |
| US7410608B1 (en) * | 2007-09-19 | 2008-08-12 | Rectorseal Corporation | Methods for manufacturing a diaphragm for an air admittance valve |
| US8043301B2 (en) | 2007-10-12 | 2011-10-25 | Spiration, Inc. | Valve loader method, system, and apparatus |
| JP5570993B2 (en) | 2007-10-12 | 2014-08-13 | スピレーション インコーポレイテッド | Valve loader methods, systems, and apparatus |
| US7846199B2 (en) | 2007-11-19 | 2010-12-07 | Cook Incorporated | Remodelable prosthetic valve |
| US8357387B2 (en) | 2007-12-21 | 2013-01-22 | Edwards Lifesciences Corporation | Capping bioprosthetic tissue to reduce calcification |
| NZ602066A (en) | 2010-03-23 | 2013-09-27 | Edwards Lifesciences Corp | Methods of conditioning sheet bioprosthetic tissue |
| US10512537B2 (en) | 2010-04-16 | 2019-12-24 | Abiomed, Inc. | Flow optimized polymeric heart valve |
| US9833314B2 (en) | 2010-04-16 | 2017-12-05 | Abiomed, Inc. | Percutaneous valve deployment |
| US8906601B2 (en) | 2010-06-17 | 2014-12-09 | Edwardss Lifesciences Corporation | Methods for stabilizing a bioprosthetic tissue by chemical modification of antigenic carbohydrates |
| US9351829B2 (en) | 2010-11-17 | 2016-05-31 | Edwards Lifesciences Corporation | Double cross-linkage process to enhance post-implantation bioprosthetic tissue durability |
| WO2012067137A1 (en) * | 2010-11-18 | 2012-05-24 | 独立行政法人国立循環器病研究センター | Base material for forming lumen-shaped tissue with valve, method for producing lumen-shaped tissue with valve, and artificial blood vessel with valve |
| US8795241B2 (en) | 2011-05-13 | 2014-08-05 | Spiration, Inc. | Deployment catheter |
| US9358107B2 (en) | 2011-06-30 | 2016-06-07 | Edwards Lifesciences Corporation | Systems, dies, and methods for processing pericardial tissue |
| WO2013044267A1 (en) | 2011-09-23 | 2013-03-28 | Pulmonx, Inc. | Implant loading device and system |
| ES2523223T3 (en) * | 2011-12-29 | 2014-11-24 | Sorin Group Italia S.R.L. | A kit for the implantation of prosthetic vascular ducts |
| EP2811939B8 (en) | 2012-02-10 | 2017-11-15 | CVDevices, LLC | Products made of biological tissues for stents and methods of manufacturing |
| US10238771B2 (en) | 2012-11-08 | 2019-03-26 | Edwards Lifesciences Corporation | Methods for treating bioprosthetic tissue using a nucleophile/electrophile in a catalytic system |
| US20140228937A1 (en) | 2013-02-11 | 2014-08-14 | Joshua Krieger | Expandable Support Frame and Medical Device |
| US9615922B2 (en) | 2013-09-30 | 2017-04-11 | Edwards Lifesciences Corporation | Method and apparatus for preparing a contoured biological tissue |
| US10959839B2 (en) | 2013-10-08 | 2021-03-30 | Edwards Lifesciences Corporation | Method for directing cellular migration patterns on a biological tissue |
| AU2015256601B2 (en) | 2014-05-09 | 2020-01-23 | Foldax, Inc. | Replacement heart valves and their methods of use and manufacture |
| FR3054609A1 (en) * | 2016-07-29 | 2018-02-02 | Plastic Omnium Advanced Innovation & Res | VENTILATION FLOW REGULATOR FOR A PRESSURIZED VEHICLE TANK. |
| EA201892397A1 (en) | 2016-10-28 | 2019-09-30 | Фолдэкс, Инк. | PROSTETIC HEART VALVES WITH ELASTIC SUPPORT STRUCTURES AND RELATED METHODS |
| US11564479B2 (en) * | 2017-10-17 | 2023-01-31 | Bestway Inflatables & Material Corp. | Inflation system and device |
| US11000369B2 (en) | 2017-12-11 | 2021-05-11 | California Institute Of Technolgy | Systems, devices, and methods relating to the manufacture of intravascularly implantable prosthetic valves |
| WO2020092205A1 (en) | 2018-11-01 | 2020-05-07 | Edwards Lifesciences Corporation | Transcatheter pulmonic regenerative valve |
| CN115076409B (en) * | 2022-08-11 | 2022-11-08 | 中国空气动力研究与发展中心设备设计与测试技术研究所 | Multi-petal type isolation water valve |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| USRE30912E (en) * | 1968-09-16 | 1982-04-27 | Hancock Laboratories, Inc. | Stent for heart valve |
| US3589392A (en) * | 1969-05-05 | 1971-06-29 | Louis C Meyer | Split leaflet check valve for cardiac surgery and the like |
| DE2742681C3 (en) * | 1977-09-22 | 1980-07-31 | Dr. Eduard Fresenius, Chemisch- Pharmazeutische Industrie Kg, 6380 Bad Homburg | Prosthetic closure element to replace the mitral and tricus pldal valve in the human heart |
| US4222126A (en) * | 1978-12-14 | 1980-09-16 | The United States Of America As Represented By The Secretary Of The Department Of Health, Education & Welfare | Unitized three leaflet heart valve |
| GB2046165B (en) * | 1979-04-11 | 1983-02-02 | Ross D N | Sharpening biomaterial |
| US4247292A (en) * | 1979-06-06 | 1981-01-27 | Angell William W | Natural tissue heart valve fixation process |
| US4340977A (en) * | 1980-09-19 | 1982-07-27 | Brownlee Richard T | Catenary mitral valve replacement |
| US4501030A (en) * | 1981-08-17 | 1985-02-26 | American Hospital Supply Corporation | Method of leaflet attachment for prosthetic heart valves |
| US4364127A (en) * | 1981-10-02 | 1982-12-21 | Research Corporation | Trileaflet type prosthetic heart valve |
| DE3248560C2 (en) * | 1982-12-27 | 1985-05-30 | Hennig, Ewald, Dr., 1000 Berlin | Method for producing an artificial heart valve |
| IT1159433B (en) * | 1983-07-25 | 1987-02-25 | Sorin Biomedica Spa | PROCEDURE AND EQUIPMENT FOR THE MANUFACTURE OF VALVE FLAPS FOR CARDIAC VALVE PROSTHESIS AND CARDIAC VALVE PROSTHESIS PROVIDED WITH SUCH FLAPS |
| NL8500538A (en) * | 1985-02-26 | 1986-09-16 | Stichting Tech Wetenschapp | HEART VALVE PROSTHESIS, METHOD FOR MANUFACTURING A HEART VALVE PROSTHESIS AND MOLD USED THEREIN |
| DE3541478A1 (en) * | 1985-11-23 | 1987-05-27 | Beiersdorf Ag | HEART VALVE PROSTHESIS AND METHOD FOR THE PRODUCTION THEREOF |
-
1988
- 1988-10-11 DE DE19883834545 patent/DE3834545A1/en active Granted
-
1989
- 1989-09-29 EP EP19890118051 patent/EP0363753B1/en not_active Expired - Lifetime
- 1989-09-29 ES ES89118051T patent/ES2076183T3/en not_active Expired - Lifetime
- 1989-10-10 US US07/420,112 patent/US5116564A/en not_active Expired - Lifetime
- 1989-10-11 JP JP26480789A patent/JP2990363B2/en not_active Expired - Fee Related
- 1989-10-11 CA CA 2000500 patent/CA2000500C/en not_active Expired - Fee Related
-
1993
- 1993-12-21 US US08/171,754 patent/US5376113A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| US5376113A (en) | 1994-12-27 |
| EP0363753B1 (en) | 1995-06-28 |
| ES2076183T3 (en) | 1995-11-01 |
| US5116564A (en) | 1992-05-26 |
| JP2990363B2 (en) | 1999-12-13 |
| DE3834545C2 (en) | 1992-08-27 |
| EP0363753A2 (en) | 1990-04-18 |
| EP0363753A3 (en) | 1991-03-27 |
| JPH02168961A (en) | 1990-06-29 |
| DE3834545A1 (en) | 1990-04-12 |
| CA2000500A1 (en) | 1990-04-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2000500C (en) | Flexible closing member, especially heart valve, and method of producing the same | |
| EP1237509B1 (en) | Implantable prosthetic valve | |
| US11382740B2 (en) | Collapsible-expandable prosthetic heart valves with structures for clamping native tissue | |
| US10864094B2 (en) | Fatigue-resistant flow regulating device and manufacturing methods | |
| US4339831A (en) | Dynamic annulus heart valve and reconstruction ring | |
| US6113631A (en) | Mitral valve prosthesis | |
| EP2709563B1 (en) | Encapsulated heart valve | |
| US4204283A (en) | Prosthetic valve | |
| US6270523B1 (en) | Expandable shielded vessel support | |
| AU562543B2 (en) | Method of leaflet attachment for prosthetic heart valves | |
| CN108969150A (en) | Reversed leaflet prosthetic valves | |
| JPS58180145A (en) | Artificial heart valve | |
| JP2000513248A (en) | Prosthetic mitral and heart valves | |
| WO2013037005A4 (en) | Prosthetic valve | |
| CN218792638U (en) | Three-valve deep vein support structure | |
| CN115105263A (en) | Three-valve deep vein support | |
| AU2008201080A1 (en) | Valvular prostheses having metal or pseudometallic construction and methods of manufacture |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |