THROMBOSIS OF MITRAL-VALVE BIOPROSTHESES IN PATIENTS REQUIRING CIRCULATORY ASSISTANCE

Two patients with new mitral valve bioprostheses required implantation of Bio-Medicus centrifugal pumps (Bio-Medicus, Minneapolis, MN) for c irculatory support and had evidence of prosthetic valve thrombosis 1 a nd 4 days later. Both patients died of thromboembolic complications de spite surgical removal of the thrombus. Thrombosis is a rare early com plication of bioprosthetic valves and in these cases was probably rela ted to low transvalvular now due to the use of circulatory assist devi ces. We discuss possible strategies for avoiding and managing this cat astrophic complication.