Eighty-five patients operated on before January 1976 have survived at least 30 days after insertion of a valved external conduit by the venous ventricle (usually the right) and the pulmonary arteries as a part of the repair of their congenital heart disease. Follow-up information is available on 83 patients, and mean follow-up time has been 27.7 months. Seven patients have required reoperation because of obstructive complications. Actuarial analysis indicates that the proportion of patients requiring reoperation is 4.0 +/- 2.8% at 2 years, 12.9 +/- 5.5% at 3 1/2 years, and 30.4 +/- 12.1% at 5 years. In five patients compression of the conduit between the sternum and heart was the primary cause of the obstruction. The proportion requiring reoperation for conduit compression is 2.0 +/- 2.0% at 2 years, 8.6 +/- 4.9% at 3 1/2 years, and 27 +/- 12.4% at 5 years. Age at operation is not related to the proportion of patients requiring reoperation, nor is the type of conduit. No patients have yet required reoperation for conduit compression whose operation has been done since we began systematically to position the conduit well away from the sternum. By actuarial analysis the proportion of patients surviving 5 years is 76.7%. Of those alive at follow-up examination, 78% were without limitation of activity.