Clinical evaluation of porcine heterograft cardiac valves in 200 patients.

Of 200 patients who received porcine heterograft cardiac valves, the first 100 did not receive postoperative anticoagulant therapy. In the second 100 patients anticoagulant measures were used when thrombogenic factors not related to the prosthesis were evident. Anticoagulation should be employed following mitral valve replacement while factors contributing to thromboembolism prevail. The conditions that tend to induce vascular stasis in the left atrium followed by embolism are chronic atrial fibrillation, a large dilated left atrium and a calcified left atrial wall. The results of our study provide assurance of the continued use of the porcine bioprosthesis.