INFECTIVE ENDOCARDITIS IN PATIENTS WHO HAD REPLACEMENT OF THE AORTIC ROOT

In 12 patients who had had composite replacement of the aortic valve a nd ascending aorta, infective endocarditis developed 2 months to 17 ye ars after operation. Six patients had mechanical valves and 6 had biol ogical ones (four homograft and two porcine valves). All patients need ed operation because of shock, heart failure, persistent sepsis in spi te of adequate antibiotic therapy, or the development of a paravalvula r false aneurysm. The predominant microorganism was Staphylococcus. Al l 6 patients who had mechanical valves were found to have an abscess i n the junction between the aortic annulus and the prosthesis; in patie nts who had biological valves the infection was limited to the leaflet s in 3 (one homograft and two porcine valves) and leaflets and annulus abscess in 3 (three homograft valves). Operation consisted of radical resection of tissues suspected of being infected and reconstruction o f the left ventricular outflow tract and of the surrounding structures with glutaraldehyde-fixed bovine pericardium. The aortic valve and as cending aorta were replaced with a new valved conduit. An aortic homog raft was used in only 1 patient. There was only one operative death du e to right ventricular infarction but most patients experienced seriou s postoperative complications. Operative survivors were followed up fr om 3 to 156 months (mean, 42 months). One patient died 35 months posto peratively due to bleeding complications of anticoagulation; 1 patient suffered a cardiac arrest at home 2 months after operation, sustained permanent cerebral damage, and died 4 months later. The remaining pat ients are asymptomatic from the cardiovascular viewpoint. There has be en no recurrent infection or formation of false aneurysm.