Tricuspid and mitral valvular disease: valve replacement.

Using the methods described, the author has performed AV-valve replacement surgery in seven clinical dogs with AV valve dysfunction. Two dogs received autologous tissue tricuspid valves, three dogs received autologous tissue mitral valves, one dog received a mechanical mitral prosthesis, and one dog received a mechanical mitral and autologous tricuspid prosthesis. The two dogs that received a tricuspid prosthesis recovered from surgery, one dog is normal nearly 3 years after valve replacement surgery, and the second dog was euthanized 3 weeks after replacement surgery because of complications related to other congenital cardiovascular defects (ie, pulmonary artery coartations). The dog that received the mechanical mitral valve prosthesis made a complete immediate postoperative recovery but died from hemorrhage complications related to a femoral artery catheter removal 3 days after surgery. Hemorrhage from the left atrium resulted in the death of one dog after implantation of a bioprosthetic mitral valve. Two dogs with mitral valve bioprostheses and one dog with a mitral and tricuspid valve replacement could not be weaned from the cardiopulmonary bypass pump, even with pharmacological support. Although the initial results in this small clinical trial have not been spectacular, it is apparent from the few clinical cases operated on that the equipment, supplies, and techniques have advanced sufficiently in veterinary surgical practice to perform AV-valve replacement surgery in companion animals. Prosthetic valves are available presently to perform such surgery even in small animal patients (5 kg). However, a significant obstacle that must be overcome before such techniques become routine is the selection of animal patients that have sufficient myocardial reserve to undergo valve replacement surgery.(ABSTRACT TRUNCATED AT 250 WORDS)