Surgical treatment for isolated hypoplasia of the right ventricle

Four patients with isolated hypoplasia of the right ventricle who underwent intracardiac repair are described. An atrial septal defect (ASD) was successfully closed in 3 patients with mild hypoplasia of the right ventricle. The remaining patients underwent ASD closure and right atrium-to-pulmonary artery connection with a conduit with a bovine pericardial valve because of severe hypoplasia of the right ventricle and tricuspid valve. Postoperative angiocardiogram in the last patient demonstrated two-channel pathways from the right atrium to the pulmonary artery via both the right ventricle and external conduit. At long-term follow-up studies, 3 patients had developed arrhythmias and/or sinus node dysfunction, and one had died, probably because of arrhythmia, 13 years postoperatively. The right ventricular ejection fractions were below normal levels at 11 and 12 years postoperatively in 2 patients who underwent closure of ASD. It was concluded that the mild form of hypoplasia of the right ventricle should be surgically corrected by ASD closure, while right atrium-to-pulmonary artery connection or Fontan's operation should be chosen for cases of severe hypoplasia. Arrhythmias and hypofunction of the right ventricle are long-term problems after intracardiac repair of this anomaly.