Abstract
Thirteen cases with mitral valve disease were operated upon with implantation of aortic pig hetero-grafts, mounted on a stainless steel ring covered with Da-cron. There were 3 early deaths, due to myocardial failure, aortic dissection, and myocardial haemorrhage, respectively. There were 3 late deaths, one due to an embolus, probably from the left atrium, one to graft failure with severe mitral regurgitation and marked haemolysis, and one to sepsis. The cause of the graft failure is unknown. There was no endocarditis in the case with sepsis. The remaining 7 cases were re-investigated with heart cathete-rization and left ventricular angiography. All cases were improved and there was no diastolic gradient over the grafts. In four there were physical or angiographical signs of minimal mitral regurgitation. Among the seven survivors only one presented laboratory findings suggestive of haemolysis.
Since the time of re-investigation, an additional four heterograft valve failures have occurred among ths survivors.