Atrioventricular septal defects. Analysis of short- and medium-term results. Atrioventricular septal defects were repaired in 87 patients from 1981 to 1988. Interventricular communications were present in 73 patients, and major associated anomalies were present in 17 (tetralogy of Fallot in four, double-outlet right ventricle in two, multiple ventricular septal defects in 11). Five deaths occurred in the hospital (5.7%; 70% confidence limits, 3.2% to 9.7%). A preoperative New York Heart Association class V functional condition was the only incremental risk factor (p = 0.02) for death in the hospital. No patient (0%; 70% confidence limits, 0% to 2.15%) had complete heart block. Actuarial survival rate at 80 months was 81.4%. The only incremental risk factor (p = 0.005) leading to reoperation was a preoperative valve incompetence. Actuarial rate at 80 months for freedom from reoperation was 84.2% in the overall group of patients after repair of atrioventricular septal defect. We conclude that an improvement in survival and success rates should be found when a policy of earlier repair is followed. 