Between May 1974 and December 1993, 37 patients (0.75%) with a double-chambered right ventricle underwent surgical repair. The patients ranged in age from 11 months to 12 years (mean 4 +/- 1.1 years). Cardiac catheterization was performed in 36 patients. The proximal right chamber pressure was 118 +/- 10 mmHg and the mean ventricular gradient pressure was 75 +/- 10 mmHg. A ventricular septal defect was present in 36 cases and fixed subaortic stenosis in eight. Longitudinal right ventriculotomy, group I, was performed in 19 patients (51.3%): 11 had a perimembranous ventricular septal defect and eight an infundibular ventricular septal defect. Combined pulmonary arteriotomy and right atriotomy, group II, was performed in 18 patients (48.7%): 17 patients had a perimembranous ventricular septal defect. The ventricular septal defect was closed using a double velour patch in 26 patients, continuous suture in four and a Gore-Tex patch in six. In the ventriculotomy group one patient died shortly after the operation (following pulmonary complication), and ten patients required inotropic support. Two patients developed patch dehiscence and underwent reoperation. There were no complications in group II patients who underwent right atriotomy. Associated cardiac anomalies were corrected in all patients. Follow-up of 6.5 +/- 3.1 years after operation showed that 36 patients were alive and asymptomatic. CONCLUSIONS the transatrial approach with pulmonary arteriotomy is an appropriate and effective double-chambered right ventricle correction even if it is associated with a perimembranous ventricular septal defect.