Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
  • A61L27/36—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix
  • A61L27/3604—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix characterised by the human or animal origin of the biological material, e.g. hair, fascia, fish scales, silk, shellac, pericardium, pleura, renal tissue, amniotic membrane, parenchymal tissue, fetal tissue, muscle tissue, fat tissue, enamel
  • A61L27/3625—Vascular tissue, e.g. heart valves
• • 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
• • 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
  • A61F2/2475—Venous valves
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
  • A61L27/36—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix
  • A61L27/3641—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix characterised by the site of application in the body
  • A61L27/3645—Connective tissue
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
  • A61L27/50—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
  • A61L27/507—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials for artificial blood vessels
• • 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
  • A61F2/2415—Manufacturing methods
• • 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
  • A61F2/2427—Devices for manipulating or deploying heart valves during implantation

Definitions

• the present invention is directed to an implant for restoring venous valvular function to a vein, and to methods of making and using the-same.
• the present invention is directed to an implant formed from venous valve tissue extracted from a quadruped or other animal source. Description of the Related Art
• blood is circulated from the arterial to the venous system, with the blood pressure being the greatest in the arterial system.
• Blood pressure in the arteries as provided by heart activity is normally sufficient to maintain the flow of -blood in one direction throughout the venous system.
• the pressure of the blood in the veins is much lower than in the arteries, principally due to the distance from the heart. Therefore, numerous venous valves are located throughout the veins to ensure that the blood travels unidirectional through the veins and towards the heart.
• venous valves The primary benefit of venous valves is the ability to limit backflow of blood travelling through the venous system.
• the normally low blood pressure in the venous system is supplemented by the contraction of skeletal muscles. The contractions of the muscles compress and drive the blood through the veins.
• the venous valves check blood flow through the veins, thereby ensuring that the blood is driven toward the heart. Therefore, damage to the venous valves disrupts this normal blood flow.
• Venous valves also evenly distribute blood in the veins by segregating portions of blood flowing through the venous system, thereby minimizing or reducing the effect of any sudden increase in blood pressure, e.g., upon heavy exertion.
• Venous valves are particularly important in the arms and legs.
• the venous system in the lower extremities generally consists of deep veins and superficial veins which lie just below the skin surface.
• the deep and superficial veins are interconnected by perforating veins.
• blood In the legs, blood generally flows upwards towards the heart and against the pull of gravity.
• Venous valves aid the forward flow of blood by closing when fiow tends to reverse, thereby preventing reflux of blood.
• Venous valves can become incompetent or damaged by disease, injury, or as a result of inherited malformation. Incompetent or damaged valves usually leak blood, even at very low blood pressures. These valves fail to prevent the backflow of blood, which is particularly troublesome in the veins of the lower extremities leading to increase in the blood pressure within the veins. The backflow of blood passing through leaking venous valves can cause numerous problems. Leaking venous valves allow for blood regurgitation (reflux), which causes blood to improperly flow back down through the veins and away from the heart. Blood can then stagnate in sections of certain veins, particularly in the veins in the lower extremities.
• blood regurgitation reflux
• Conservative treatment include the use of elastic stockings and the application of antibiotics, proteolytic enzymes and UNNA Boots. These measures, however, are usually inadequate for most conditions. Other procedures involve surgical operations to repair, reconstruct, or replace the incompetent or damaged valve. Attempts have been made to repair incompetent valves by surgically restricting the valve circumference, such as by suturing the vein to form a tighter closing or restrict dilation of the valve. Other attempts have been made to restrict dilation of the valve by application of a prosthetic graft around the vein.
• Valvuloplasty involves the surgical reconstruction of the valve
• Transplantation involves surgically transpo ⁇ ding one or more of the patient's healthy venous valves for the incompetent or damaged valve.
• Transposition of veins can include surgically bypassing sections of veins possessing the incompetent or damaged valves with veins possessing competent valves.
• venous valves are generally thin, once the valve becomes incompetent or destroyed, any repair provides only marginal relief. Further, venous valves are usually damaged during handling when the venous valve is being reconstructed, transpositio ⁇ ed or transplanted. The endothelium tissue layer of the vein may also be damaged during handling, which reduces the viability of the vein graft after implantation.
• a not very useful alternative to the preceding surgical procedures is to remove the valve completely.
• the removal of an incompetent valve will prevent an impediment to normal blood flow, however, the problem associated with backflow is usually worsened by simply removing the valve. Therefore, in many applications, it is desirable to replace the damaged valve with a suitable valvular prosthesis that functions similarly to a natural venous valve.
• a design of an artificial venous valve prosthesis was reported in "Development of a Prosthetic Venous Valve,” Schmidt et al., Journal of Biomedical Materials Research, Vol. 19, pages 827 832 (1985).
• One type of artificial valve was constructed by molding glutaraidehyde fixed, umbilical cord segments. Specially treated segments were placed over the end of an aluminum rod which had been sculpted into a bicuspid shaped valve.
• Another type of artificial valve was prepared by dip casting a mandrel in liquid Pellethane polymer. The prepared casting was cut with a scalpel to define the separate valve leaflets.
• valves have diameters and heights larger than that of the usual venous valves, and leaflets with thicknesses many times that of the human or animal venous valve leaflet. Thus, such valves become inflexible to venous flow passage and the low pressures of that system.
• a titanium venous valvular prosthesis has been used in animal experiments. See, "Experimental Prosthetic Vein Valve,” Syde A. Taheri et al., The American Journal of Surgery, Vol. 156, pages 1 11-114 (1988).
• a titanium venous valve was fashioned after the shape of a prosthetic heart valve. The major disadvantage with this type of prosthesis is that such valves require treatment of the patient with anti-coagulants.
• Xenograft monocusp patches were examined for possible use in repairing incompetent venous valves. See,
• Other xenograft patches have been suggested to replace a single damaged leaflet of a multi-leaflet valve. See, U.S. Patent No. 5,500,014, issued to Quijano et al.
• the present invention provides a biological venous implant formed from a leaflet of a venous valve.
• the terms "open” and “closed” refer to the state of the valve. That is, when the leaflet is in an open position, the leaflet is generally in close proximity to the wall of the vein such that the venous valve is open. When the leaflet and thus the valve are in a closed position, the leaflet is a distance away from the vein wall such that the leaflet substantially prevents backflow of blood through the vein. Thus, the leaflet is prepositioned to open under normal forward blood flow conditions, and to close under minimal backflow pressure.
• a method is provided for restoring venous valvular function within a valve-deficient vein of a patient.
• the method includes extracting a vein segment from a biological source other than the patient.
• the vein segment has a venous valve with a single leaflet formed therein.
• a patch having a single leaflet formed thereon is formed from an excised wall section of the vein segment.
• the patch is attached to the valve deficient vein of the patient such that the leaflet opens and closes in response to changes in blood flow within the vein.
• the vein segment is preferably extracted from the jugular vein of a bovine, equine, ovine, caprine, or cervine animal source.
• a valvular implant in accordance with another aspect of the invention, includes an excised wall section of a vein segment from a biological source and a single valvular leaflet formed thereon The leaflet is movable between an open position in which a substantial portion of the leaflet is in close proximity to the wall section, and a closed position in which a substantial portion of the leaflet is a distance away from the wall section
• the leaflet is of a sufficient size to substantially prevent backflow of blood through the patient's vein when in the closed position.
• the vein segment is extracted from the jugular vein of an animal source, such as bovine, equine, ovine, caprine or cervine.
• a method for constructing a valvular patch for implantation into a valve-deficient vein of a patient.
• a vein segment is extracted from a biological source other than the patient.
• the vein segment includes a venous valve having at least one leaflet.
• a wall section having a single leaflet formed thereon is excised from the vein segment.
• the wall section can be surgically shaped to a desired size and shape.
• the leaflet is selected such that the size of the leaflet is sufficient to substantially occlude the vein of the patient when the leaflet is in a closed position.
• FIG. 1A is a perspective view of a partial section of a valvular implant in accordance with an embodiment of the invention within a vein of a patient, the valvular implant having a single leaflet in a substantially closed position;
• Figure 1B is a perspective view of a partial section of the valvular implant of Figure 1 A with the valvular leaflet in a substantially open position;
• Figure 2 is a plan view of the inside surface of an extracted vein segment that has been cut longitudinally to expose the leaflets of a venous valve;
• Figure 2A is a plan view of a patch shaped in a semi-sinus configuration
• Figure 2B is a side view of the patch of Figure 2A
• Figure 2C is a plan view of a patch shaped in a no-sinus configuration
• Figure 2D is a side view of the patch of Figure 2C
• Figure 3 is a perspective view of a valve deficient vein of a patient in which the valvular implant is to be implanted, illustrating an incision within the patient's vein;
• Figure 4 is a perspective view of a monocusp valvular patch partially sewn to a portion of the patient's vein at the site where the incision is made;
• Figure 5 is a plan view of the outer surface of the patient's vein after the monocusp valvular patch has been completely sewn within the patient's vein;
• Figure 6 is a perspective view of a partial section of a patient's vein in which two valvular patches, each having a single leaflet, are implanted in the patient's vein in accordance with another embodiment of the present invention
• Figure 7 is a perspective view of a partial section of a patient's vein in which a valvular patch having two leaflets is implanted in the patient's vein in accordance with another embodiment of the present invention, the leaflets being in a substantially closed position;
• Figure 8 is a perspective view of a valvular implant attached to a holding device; and Figure 9 is a top plan view of a base portion of the holding device shown in Figure 8.
• the present invention relates generally to a biological valvular implant and to methods of making and using the implant.
• the present invention is directed to an implant formed from venous valve tissue extracted from a quadruped or other animal source.
• Venous valves normally remain open during forward flow, i.e. flow of blood towards the heart, through the vein.
• the leaflets of the valve are in an "open” position when a venous valve is open, and the leaflets are in a "closed” position when the venous valve is closed.
• Normal flow rate of blood through the veins is generally at least 100 milliliters per minute (ml/m), and approximately 250 ml/m to about 550 ml/m.
• the valves close upon the exertion of backflow pressure.
• backflow is used to describe flow in a direction away from the normal forward blood flow, such as in a direction away from the heart or away from the deep veins.
• FIG. 1A illustrates a valvular implant 100 according to a preferred embodiment of the present invention implanted within a patient's vein 102.
• the valvular implant 100 is made from a vein segment from a biological source.
• the valvular implant 100 includes a valvular leaflet 104 and a wall section 106 of the harvested vein segment.
• the wall section 106 of the valvular implant is attached to the vein 102 of the patient as a patch to form a continuous vein wall.
• the leaflet 104 of the valvular implant is movable between an open and a closed position.
• the arrows indicate the direction of the backflow of blood within the patient's vein 102, and in this illustration, the backflow pressure is sufficient to cause the single leaflet 104 of the valvular implant to substantially close, thereby closing the valve.
• the size of the leaflet 104 is selected such that a single leaflet 104 is sufficient to substantially occlude the vein, as shown in Figure 1A, when the leaflet 104 is in a closed position.
• a valvular leaflet 104 is very thin, often being about 0.003 of an inch or less.
• the thin, flexible nature of valvular leaflets enables the leaflet 104 of the implant 100 to close under low pressure. Thicker types of tissue, such as pericardial tissue, require greater backflow pressure in order for the leaflet to close.
• pericardial tissue is fibrous and is subject to fraying.
• Figure 1B illustrates the leaflet 104 of the valvular implant in a substantially open position.
• the leaflet 104 of the valvular implant is pushed generally against the inner surface of the patient's vein 102 to allow blood to flow normally through the vein 102.
• valvular implant 100 functions as a venous valve.
• the valvular implant 100 is prepared from a harvested vein segment having a valve with one or more leaflets formed therein. It is not necessary that the valve within the harvested vein segment be a competent or intact valve because only a portion of the valve, i.e. only a single leaflet in some instances, is used to form the valvular implant 100.
• venous valves include one, two or three leaflets which form the valve.
• the venous valve of the harvested vein segment can have one or more leaflets. In a preferred embodiment, only a single valvular leaflet 104 is needed to form the valvular implant 100. In other embodiments, however, it may be desirable to use two or more leaflets to form the valvular implant 100.
• Venous valves can be found in veins upon which gravity acts, such as in veins located in the limbs or the jugular veins of quadrupeds. Venous valves can also be located in other parts of the body.
• the stomach may contain venous valves.
• the vein segment 112 is preferably extracted from a biological source other than the patient in which the valvular implant 100 will be implanted.
• the vein segment 112 can be extracted from a bovine, equine, ovine, caprine or cervine animal source.
• Figure 2 illustrates a harvested vein segment 112 which has been cut longitudinally to transform the vein segment 112 from a generally cylindrical shape to a generally flat shape.
• the vein segment 112 includes a wall section 106 and two leaflets 104, one of which has been bisected by the cutting operation. Other vein segments can have other numbers of leaflets which form the valve.
• the number of leaflets 104 within a vein segment will vary depending on the type of animal and type of venous valve from which the vein segment 112 is extracted.
• the size of the leaflet and the number of the leaflets which form the venous valve will also vary depending on the source of the vein segment 112.
• the wall section 106 has an inner surface 108 and an outer 110 surf ace (shown in Figure 5).
• the leaflets 104 are attached to the inner surface 108 of the wall section 106.
• the harvested vein segment 112 is fixed. Fixation can be accomplished in a variety of ways known to those skilled in the art, including but not limited to, exposure to a chemical fixation solution, UV light or freeze drying. Various ways of fixing the vein segment 112, including subjecting the vein segment to a chemical tanning process, are described in detail in U.S. Patent No. 5,500,014, issued to Quijano et al., which is incorporated herein by reference.
• Tanning is a well-known process involving the treatment of the vein segment with a suitable fixing agent, such as an aldehyde solution.
• a suitable fixing agent such as an aldehyde solution.
• a solution of glutaraldehyde in a pH balanced electrolyte buffer is used as the fixing agent.
• a concentration of glutaraldehyde should include approximately 0.025 percent to about 0.626 percent of the tanning solution to prepare supple valve leaflets.
• the fixation process can be expedited by maintaining the fixation solution at higher temperatures.
• the harvested vein segment 112 can be fixed with the valve in an open or a closed position, or by cycling between the open and closed positions.
• the chemical fixing of the valve leaflets in a substantially open position is provided by subjecting the harvested vein segment to a tanning process while maintaining a substantially constant flow of tanning fluid through the vein segment 112.
• the extent to which the valve leaflets 104 are open is controlled by varying the flow rate of the tanning solution through the vein segment 112 during the fixation process.
• the resulting implant will have the leaflets fixed anywhere from a completely open valve to about 10 to 70 percent of the normal open position of the valve.
• the valve leaflets 104 are fixed such that the valve is in a substantially open position, in other embodiments, however, it is suitable to fix the valve leaflets with the valve in a closed position or by cycling between an open and a closed position. Fixing the leaflets with the valve in a closed position is performed by reversing the flow of the fixation solution through the vein segment and maintaining a minimal backflow pressure against the valve leaflets Typically, the pressure applied against the leaflets in this position is approximately 0.1 mm Hg. In certain embodiments, the leaflets are subjected to a low concentration fixation solution to maintain the flexibility of the valve leaflets.
• the concentration of aldehyde in the tanning solution and the amount of time to which the tissue is subjected to the tanning solution affect the stiffness of the tissue.
• the flexibility and suppleness of the leaflets allows the leaflets to close the valve under a minimal backflow.
• the concentration of the aldehyde, e.g. glutaraldehyde, in the tanning solution is preferably from about 0.025 percent to about 0.626 percent of the tanning solution to prepare flexible, supple valve leaflets.
• the glutaraldehyde is about 0.15 percent of the tanning solution.
• Other suitable tanning solutions include acrolein or polyepoxy compounds.
• the outer surface 110 of the wall section 106 of the vein segment 112 is subjected to a fixation solution having a higher concentration of glutaraldehyde than the solution to which the leaflets are subjected.
• the tanning solution for fixing the wall section 106 of the vein segment contains about 2.5 percent of glutaraldehyde, while the tanning solution to which the leaflets 104 are exposed contains 2.5 percent of glutaraldehyde.
• the higher concentration of glutaraldehyde makes the wall section 106 stiff er and less flexible than the leaflets 104.
• an incision or cut 109 is made in the wall of the vein segment 112 around the intact leaflet 104.
• the leaflet and wall portion can be excised from the vein segment prior to fixation.
• the single leaflet 104 and wall portion 106 form a valvular patch.
• a valvular patch 100 having only a single leaflet 104 is referred to as a monocusp patch.
• a valvular patch can also be formed from a wall section having two or more leaflets.
• the valvular patch 100 is surgically shaped to an appropriate size and shape, in some instances, a patch 100 of the desired size and shape is cut directly from the vein segment 112 so that additional shaping is not necessary.
• the wall section 106 of the resulting patch 100 has a generally elliptical shape, i.e., full-sinus configuration, as shown in Figure 2.
• Figures 2A and 2B illustrate a patch having a wail section shaped in a semi-sinus configuration and Figures 2.
• 2D illustrate a patch having a wall section with a no-sinus configuration.
• the reduced sinus area of the patches shown in Figures 2A-2D requires less removal of the patient's vein in order to implant the patch. Further, the amount of suturing necessary for implementation is also reduced in those embodiments.
• the patch 100 is attached to a valve-deficient vein 102 of a patient by suturing a perimeter of the patch to a wall of the patient's vein 102.
• an incision is made in the vein 102 of a patient in which the valvular patch 100 is to be implanted.
• Tissue may be removed from the vein 102 as is necessary in order to accommodate attachment of the valvular patch within the patient's vein 102. For instance, a portion of the wall of the patient's vein may need to be removed to allow the vein to receive the valvular implant 100.
• the valvular patch may be implanted at the same location within the patient's vein where an incompetent or damaged valve exists. In these cases, it is not necessary to remove the dysfunctional valve in order to implant the patch. Thus, when a patch is used the patient's native vein tissue is conserved.
• the wall section 106 of the valvular patch 100 is attached at the incision site on the patient's vein 102.
• the valvular patch 100 can be attached to the vein 102 by suturing or otherwise attaching the wall portion 106 of the patch to the patient's vein wall, such as with biocompatible adhesives.
• Figure 5 is a side view of the patient's vein 102 after the patch 100 is sutured to the vein.
• the outer surface 100 of the wall section of the patch is flush with the outer surface of the vein wall.
• the leaflet 104 of the valvular patch 100 acts as a substitute valve.
• the desired size of the leaflet 104 will vary depending on the size of the vein in which the valvular implant 100 is to be implanted.
• the single leaflet 104 is preferably selected to be of a sufficient size to substantially prevent backflow of blood through the patient's vein when the leaflet 104 is in a closed position.
• the leaflet 104 acts as a competent venous valve and restores valvular function to the patient's vein.
• a valvular leaflet from the jugular vein of a large animal may be of a sufficient size to form a valve within a human vein.
• Figure 6 illustrates a patch having two leaflets 104, 107 implanted within the vein of a patient. In a closed position, each leaflet covers about half the cross-sectional area of the vein.
• FIGS. 7 and 8 illustrate a holding device 118 for holding the valvular patch 100 in position while attaching the patch 100 to the patient's vein 102.
• the holding device 118 includes a base portion 120 and detachable holder 122.
• the base portion 120 has a perimeter portion 124 and a plurality of suture holes 126 along the perimeter portion 124 of the base 120.
• the base perimeter portion 124 is sized and shaped generally similar to the desired size and shape of the valvular patch 100.
• the size of the base portion 120 can be slightly smaller than the desired size of the patch so that a small amount of tissue is exposed along the base perimeter 124.
• the perimeter portion 124 has a generally elliptical shape.
• Other configurations, including construction and shape, of the base 120 and perimeter portion 124 are also possible.
• the base portion 120 can have a continuous flat surface, rather than the wheel and spoke configuration shown in Figures 7 and 8.
• the perimeter portion 124 of the base portion 120 is placed against the outer surface 110 of the wall section 106 of the harvested vein segment 112.
• the wali section 106 of the vein segment 112 is sutured to the base perimeter
• the vein segment 112 can be attached to the base 120 in ways other than suturing, such as using adhesives.
• a wall section 106 is cut from the vein segment 112 to form the valvular patch 100
• the valvular implant 100 can be stored, shipped, and/or sold with the base portion 120 attached to it.
• the base 120 can be used to identify the size of the patch 100.
• the base portion 120 can be marked with the size of the leaflet 104.
• the holder 122 is attached to the base portion 120 at a threaded location 128 to facilitate handling of the valvular patch 100.
• the holder comprises an elongate rod 130 threaded at its distal end and having a handle 132 at its proximal end.
• the holder 122 and handle 132 can have other shapes which facilitate handling of the implant.
• the holder 122 can be detached from the base 120 during storage or transport of the patch 100, and can be attached to the base 120 for use during surgery to facilitate positioning and manipulation of the patch 100 at the desired location within the patient's vein. Once the patch 100 is attached to the patient's vein, the base 120 can be removed from the patch 100 by removing the sutures.

Landscapes

• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Chemical & Material Sciences (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Veterinary Medicine (AREA)
• Public Health (AREA)
• General Health & Medical Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• Cardiology (AREA)
• Vascular Medicine (AREA)
• Transplantation (AREA)
• Epidemiology (AREA)
• Medicinal Chemistry (AREA)
• Dermatology (AREA)
• Heart & Thoracic Surgery (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Botany (AREA)
• Zoology (AREA)
• Urology & Nephrology (AREA)
• Molecular Biology (AREA)
• Prostheses (AREA)

Applications Claiming Priority (5)

Publications (1)

Family

ID=26830835

Family Applications (1)

Country Status (3)

Families Citing this family (17)

Family Cites Families (7)

• 2000
  • 2000-04-28 WO PCT/US2000/011414 patent/WO2000067679A1/en not_active Application Discontinuation
  • 2000-04-28 EP EP00928503A patent/EP1187581A1/de not_active Withdrawn
  • 2000-04-28 AU AU46737/00A patent/AU4673700A/en not_active Abandoned

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events