Method of replacing atrioventricular heart valves using flexible tubes

• US 5,824,063 A
• Filed: 11/14/1996
• Issued: 10/20/1998
• Est. Priority Date: 11/01/1993
• Status: Expired due to Term

• Current Assignee: 3F Therapeutics Incorporated (Medtronic Plc)
• Original Assignee: 3F Therapeutics Incorporated (Medtronic Plc)
• Inventors: Cox, James L.
• Primary Examiner(s): Yu, Mickey
• Assistant Examiner(s): CUDDIHY, FRANCIS KEVIN
• Application Number:
  US08/749,335
• Time in Patent Office: 705 Days
• Field of Search: 623/1, 623/2, 623/3, 623/900, 623/66, 623/901, 206/438, 128/898, 435/238
• US Class Current: 623/2.1
• CPC Class Codes: A61F 2/0095 Packages or dispensers for prostheses or other implants for intraocular lenses A61F2/1691; for dental surgery A61C19/02
• CPC Class Codes: A61F 2/2412 with soft flexible valve members, e.g. tissue valves shaped like natural valves check valves with flexible valve members in general F16K15/14
• CPC Class Codes: A61L 2430/20 for reconstruction of the heart, e.g. heart valves
• CPC Class Codes: A61L 27/3604 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
• CPC Class Codes: A61L 27/3629 Intestinal tissue, e.g. small intestinal submucosa
• CPC Class Codes: A61L 27/3641 characterised by the site of application in the body materials for artificial blood vessels A61L27/507; materials for use in artificial skin A61L27/60
• CPC Class Codes: A61L 27/3645 Connective tissue
• CPC Class Codes: A61L 27/3843 Connective tissue
• CPC Class Codes: A61L 27/507 for artificial blood vessels apparatus for applying cells on a blood vessel prosthesis A61F2/062
• CPC Class Codes: G06Q 40/04 Trading; Exchange, e.g. stocks, commodities, derivatives or currency exchange
• CPC Class Codes: Y10S 623/90 Stent for heart valve
• CPC Class Codes: Y10S 623/901 Method of manufacturing prosthetic device

Abstract

This invention comprises a method of using tubular material to replace an atrioventricular (AV) heart valve (i.e., a mitral or tricuspid valve, positioned between an atrial chamber and a ventricular chamber) during cardiac surgery. Preferably, the tubular material should be inherently tubular; i.e., it should be created in tubular form from its inception, rather than by using a longitudinal suture line or other seam to convert a flat sheet of material into a tubular shape. Suitable tubular materials include (1) biocompatible synthetic materials which are manufactured in tubular form, by methods such as extrusion or coating a cylindrical molding device, using material which is sufficiently thin and flexible to serve as leaflets in AV heart valves; and (2) a segment of submucosal tissue harvested from a small intestine, either from the patient who is undergoing the cardiac surgery, or from an animal or human cadaver if the harvested tissue is properly treated to reduce antigenicity. To create a replacement AV valve, the inlet of the tubular segment is sutured to the mitral or tricuspid valve annulus, after the native valve leaflets have been removed. The outlet end of the tube is trimmed or sculpted into leaflets, and the distal ends of the leaflets are sutured to papillary muscles in the ventricle, in a manner which causes the leaflets to "approximate" (close together), during systolic contraction of the heart, in a configuration that resembles the line of commissure created by healthy native leaflets. This generates flow patterns that closely duplicate the flow patterns of native AV valves.

Claims

1. A method of surgically creating an atrioventricular replacement valve in a patient'"'"'s heart, comprising the following steps:

a. creating a tubular segment having an inlet end, a thin and flexible wall portion having diametrically opposing sides, and an outlet end;

b. surgically removing from the patient'"'"'s heart an atrioventricular valve which does not function properly, thereby generating an unoccupied valve annulus between an atrial chamber and a ventricular chamber, wherein removal of the atrioventricular valve includes removal of native valve leaflets and at least some chordae tendinae while leaving at least some papillary muscles intact in the ventricular chamber;

c. circumferentially securing the inlet end of the tubular segment to the unoccupied valve annulus;

d. coupling selected portions of the outlet end of the tubular segment to papillary muscles in the ventricular chamber, in a manner which allows the flexible wall portion of the tubular segment to be manipulated by fluid pressure so that the opposing sides of the tubular segment will open during diastole and close during systole, in a manner similar to leaflets in a natural atrioventricular valve, wherein opposing sides of the tubular segment during systolic contraction of the heart creates a line of commissure which resembles native leaflet commissure, thereby preventing backflow of blood into the atrial chamber during systole without impeding flow through the replacement valve during diastole.

2. The method of claim 1 wherein the tubular segment is inherently tubular, and is characterized by an absence of any longitudinal seams.

3. The method of claim 1 wherein the tubular segment consists essentially of synthetic material.

4. The method of claim 1 wherein the atrioventricular replacement valve is created without utilizing a stent or annuloplasty ring, and wherein the tubular segment is sutured directly to the valve annulus.

5. The method of claim 1 wherein the atrioventricular replacement valve is created by utilizing an annuloplasty ring to provide a bridge between the valve annulus and the inlet end of the tubular tissue segment.