Single ventricle palliation: greater risk of complications with the Fontan procedure than with the bidirectional Glenn procedure alone

BACKGROUND: This study was performed to evaluate and compare the early, intermediate, and long-term outcomes of the bidirectional Glenn procedure and Fontan procedure in patients who live at moderately high altitude. METHODS: The outcome of each method of palliation for patients with a functionally single ventricle was retrospectively evaluated from a review of medical records. RESULTS: The bidirectional Glenn procedure was performed in 177 patients from October 1984 to June 2004. The Fontan procedure was performed in 149 patients from June 1978 to June 2004. Cardiovascular death or heart transplantation occurred in 8% of patients after the bidirectional Glenn procedure and 17% of patients after the Fontan procedure. Complications of systemic thromboembolic events, bleeding associated with anticoagulation therapy, protein losing enteropathy, and arrhythmias requiring implantation of a pacemaker, cardioversion, or radiofrequency ablation occurred in 7% of patients after the bidirectional Glenn procedure and 47% of patients after the Fontan procedure. Cardiovascular deaths and heart transplantation occurred less frequently when the Fontan procedure was performed in patients with a previous bidirectional Glenn procedure. However, the actuarial transplant-free survival and freedom from complications was not superior for a subgroup of patients who had a Fontan procedure after a bidirectional Glenn procedure in comparison to a subgroup of patients who had a bidirectional Glenn procedure alone. CONCLUSIONS: The bidirectional Glenn procedure can be used for long-term palliation of patients with a functionally single ventricle. Additional palliation with a Fontan procedure may increase the risk of stroke, protein losing enteropathy and arrhythmias without improving survival.