Intermediate procedures after first-stage Norwood operation facilitate subsequent repair.

Actuarial analysis of survival after first-stage palliative reconstructive operation for hypoplastic left heart syndrome has revealed a high out-of-hospital attrition rate over the first 18 months to 2 years postoperatively. Some of this mortality is related to development of anatomical problems such as restrictive atrial septal defect, neoaortic arch obstruction, and pulmonary artery distortion. The bidirectional Glenn shunt has proved to be an ideal adjunctive procedure for high-risk patients at the time of operation to correct such intermediate-term problems. The fenestrated Fontan procedure, which involves fenestration of the interatrial baffle placed as part of our current standard Fontan procedure, is applied for patients considered to be at moderate risk for a Fontan procedure. The decision regarding closure of the fenestration is made by hemodynamic study including temporary balloon occlusion of the fenestration. The fenestration is closed with the double-clamshell device, which is placed percutaneously in the catheterization laboratory and which is currently used for secundum atrial septal defect closure. Appropriate selection of patients for the bidirectional Glenn shunt or fenestrated Fontan procedure with or without fenestration closure has resulted in a dramatic decrease in mortality and morbidity for patients with all forms of single ventricle and for patients with hypoplastic left heart syndrome.