Multiple and single ventricular septal defect. A clinical and haemodynamic comparison.

Abstract
The clinical, hemodynamic and therapeutic data were compared in 52 children with isolated single ventricular septal defect, and 40 children with multiple ventricular septal defects as the sole cardiac anomaly. Cardiac catheterization and angiocardiography were carried out between 1966 and 1975 in the multiple ventricular septal defects group, and in 1973 in the single ventricular septal defect group. The presenting symptoms, signs and chest X-rays of the 2 groups were indistinguishable. Left axis deviation was found on the ECG in 40% of the patients with multiple defects as opposed to 10% with single ventricular septal defects (P < 0.01). In these patients the frontal QRS loop was superiorly orientated and counterclockwise, but in contrast to patients with atrioventricular defects, this feature was usually seen in the absence of complete right bundle-branch block or prolongation of the PR interval. A pulmonary vascular resistance exceeding 5 units/m2 was seen equally frequently in both groups, but not in those under 2 1/2 yr of age. The total mortality from the time of presentation, with and without operation, for patients with multiple ventricular septal defects was 20% as opposed to 4% for patients with single ventricular septal defect. Infants with intractable heart failure from multiple ventricular septal defects were treated by banding (mortality 8.3%) and subsequently debanding and multiple ventricular septal defect closure (mortality 27%). Where operation for multiple ventricular septal defects was delayed beyond the age of 1 yr, primary total correction was performed, with a mortality of 18%.