The approach to muscular ventricular septal defect has been controversial. Traditional approaches have included pulmonary artery banding or right ventriculotomy. Left ventriculotomy has been employed in older children because of the ease of exposure in the absence of trabeculations, but concern has been raised regarding potential loss of left ventricular function. Four infants less than 4 months of age underwent repair of a large muscular ventricular septal defect by left ventriculotomy. One infant had no associated defects; 2 had undergone previous coarctation repair (1 with pulmonary artery banding); and 1 had a large secundum atrial septal defect. All had congestive heart failure refractory to maximal medical management. All patients survived, and there was no myocardial dysfunction. Echocardiographic indices of ventricular function 3 to 24 months postoperatively were normal (mean shortening fraction, 32.5%). Left ventriculotomy with patch closure of the ventricular septal defect provides a simple approach to a large muscular ventricular septal defect in infants with heart failure.