We report the use of a recently developed stentless porcine valve in a 2-year-old child with truncus arteriosus communis (type I). The child had received no previous surgical palliation. Despite a markedly increased pulmonary arteriolar resistance the right ventricle was connected to the pulmonary artery with a homograft. The postoperative course was complicated at first by right ventricular failure due to pulmonary hypertension and secondarily by left ventricular failure caused by rapidly increasing truncal valve incompetence. Because we did not have a suitable homograft at hand we replaced the truncal valve with a stentless porcine xenograft valve.