CURRENT CONCEPTS IN PEDIATRIC CARDIOVASCULAR SURGERY

Abstract

AMONG the many interesting congenital cardiac malformations amenable to surgery today, four will be discussed, namely, coarctation of the aorta, ventricular septal defect, Tetralogy of Fallot, and transposition of the great vessels. Recommendations for surgical therapy are based on the experience at the Mayo Clinic. Coarctation of the aorta continues to be most satisfactorily treated by operation and the hospital mortality risk is extremely low. In general, the optimal age for surgery is about 10 to 12 years. Unusually severe systemic hypertension or cardiac enlargement constitute an indication for somewhat earlier surgery. When infants with isolated coarctation of the aorta show severe cardiac failure, and this certainly occurs although uncommonly, operation should be advised at that age. The risk even then is very low, but few cases may require reoperation at age 12 because of failure of adequate growth of the anastomosis. The indications for repair of ventricular septal defect must take into account the estimated size of the lesion and its hemodynamic effects. Patients with small ventricular septal defects who have normalsized hearts and normal electrocardiograms, that is, those without clinical evidence of significant hemodynamic derangement, are not advised by us to undergo repair of the defect at present. Patients with ventricular septal defect and mild or moderate pulmonary artery hypertension (that is, patients whose pulmonary artery pressure is less than 75% of systemic artery pressure) can be operated upon at essentially no hospital risk. Operation is clearly advisable in all of these patients. Patients with ventricular septal defect who have severe pulmonary artery hypertension associated with a large pulmonary blood flow (and thus with only mild elevation of pulmonary vascular resistance) can be operated upon with a low hospital mortality rate, in the neighborhood of 5%.