Bacterial endocarditis occurring after open-heart surgery.

A review was made of 520 patients who survived cardiopulmonary bypass for repair of congenital or acquired heart disease between 1956 and 1965. The incidence of early and late bacterial endocarditis was 2.7%, a figure which was higher than the reported incidence in the pre-bypass era but comparable to the experience reported by others. When those patients who had ball-valve prostheses inserted were considered separately, endocarditis was found to have occurred in 3.9%. The most common infecting organism was Staphylococcus albus (nine of 14 cases). Twelve of the 14 patients died, most often from complications of the infection, such as disruption of patches and prosthetic valves. The infections were difficult to control and in three patients recurred from one to three times. There was no apparent source of infection. Six patients developed infections six to 45 months after operation; the remaining eight had proved endocarditis within two months of operation. With one possible exception, treatment with antibiotics appeared to be ineffective in eradicating the infection unless foreign material was removed from the heart.