Infective endocarditis complicating congenital heart disease.

The pathological alterations in 34 patients with infective endocarditis complicating congenital heart defects were studied. The overall incidence of infective endocarditis in patients with major congenital cardiac defects was 4,7%. Most patients were under 31 years of age and males predominated. The infection was associated with Fallot's tetralogy in 10 patients (17%), ventricular septal defect in 7 (4%), bicuspid aortic valve in 7 (16%), coarctation of the aorta in 6 (8%), atrial septal defects in 2 (1%), and patent ductus arteriosus and pulmonary artery branch stenosis in 1 patient each. The causative micro-organisms were successfully cultured from only 29% of patients. Fourteen of the 34 patients had infection of an associated 'jet' lesion. Patients with isolated ventricular septal defect showed tricuspid valve endocarditis more commonly than did patients with Fallot's tetralogy. The infection had been missed clinically in 34,8% of patients, 50% of whom were aged 3 years or younger.