EARLY AND LATE RESULTS OF REPAIR OF TETRALOGY OF FALLOT WITH SUBARTERIAL VENTRICULAR SEPTAL-DEFECT - A COMPARATIVE-EVALUATION OF TETRALOGY WITH PERIMEMBRANOUS VENTRICULAR SEPTAL-DEFECT

Between November 1966 and December 1990, 511 pediatric patients with t etralogy of Fallot underwent corrective operation at Tenri Hospital. T here were 78 patients with subarterial ventricular septal defect. Mean age at repair was 5.6 +/- 3.3 years. The method of right ventricular outflow tract reconstruction was simple infundibulectomy in 14 patient s, right ventricular outflow patch in 36, and transannular patch in 28 . There were 7 (9.0%) early deaths as a result of low cardiac output s yndrome and acute renal failure. The pressure ratio of the right ventr icle to the left ventricle was 0.62 +/- 0.18 during the early postoper ative catheterization. Follow-up was achieved for 442.6 patient-years and ranged from 0.5 to 27 years, with an average of 8.5 +/- 6.7 years. There were three late deaths (2 cardiac and 1 noncardiac). Actuarial survival was 94.8% +/- 4.0% at 20 years, Catheterization during late f ollow-up (6.8 +/- 4.7 years after repair) was done in 53 patients and the pressure ratio of the right ventricle to the left ventricle was 0. 48 +/- 0.21. Fifteen patients underwent subsequent operation because o f residual lesions, including ventricular septal defect in four patien ts, pulmonary stenosis in nine, combined ventricular septal defect and pulmonary stenosis in one, and pulmonary regurgitation in one, with n o mortality. Actuarial rate of freedom from reoperation was 71.1% +/- 8.0% at 10 years and 58.8% +/- 16.8% at 20 years. Patients with tetral ogy and subarterial ventricular septal defect were more likely to have the development of residual obstruction at the level of the pulmonary valve anulus after repair than were those with tetralogy and perimemb ranous ventricular septal defect.