Method of replacing atrioventricular heart valves using flexible tubes

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.