Between January 1977 and October 1991, 47 consecutive patients with atrioventricular discordance, ventriculoarterial discordance, and two ventricles underwent intracardiac repair at the Heart Institute of Japan. Their ages at operation ranged from 2 months to 21 years (average 9.2 years) and period of follow-up ranged from 1 month to 168 months (average 65.1 months). There were five basic anatomic types according to the associated anomalies, grouped into (1) situs solitus, ventriculoarterial (V-A) discordance or
double-outlet right ventricle (DORV),
ventricular septal defect (VSD) and pulmonary outflow tract obstruction (POTO) (31 patients); (2) situs solitus, V-A discordance and VSD (6 patients); (3) situs solitus, V-A discordance and
tricuspid regurgitation (
TR) (2 patients); (4)
situs inversus, V-A discordance or DORV, VSA and POTO (7 patients); (5)
situs inversus, V-A discordance and VSD (1 patient). TR was evident preoperatively in 13 patients (28% of 47 patients), one of whom had
Ebstein's anomaly. The conventional operation, which consisted of closure of VSD (34 patients), posterolateral pulmonary outflow enlargement (2 patients), tricuspid valvuloplasty (2 patients), and tricuspid replacement (1 patient) using the anatomical right ventricle as the systemic ventricle, was performed in 35 patients (RV group). The anatomic correction (so-called "
double switch operation"), the new alternative operation using the anatomical left ventricle as the systemic ventricle, was achieved in 12 patients (LV group). Anatomic correction consisted of Senning and RV-PA ECR in 3, Mustard and RV-PA ECR in 4, Senning and arterial switch in 2, and Mustard and arterial switch in 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS)