Purpose of review: As perioperative survival following the Fontan procedure has improved and more patients are reaping the benefits of physiologic palliation, the costs of longstanding systemic venous hypertension and the functional limitations of a single ventricle are becoming clearer. Arrhythmias, heart failure, protein-losing enteropathy, hepatic cirrhosis, pulmonary hypertension, and ventricular dysfunction are common in late survivors and result in significant morbidity and mortality. Current research is focused on characterizing late morbidities and developing risk-prediction models for worse outcomes in long-term survivors.
Recent findings: Ten-year survival following the Fontan procedure is now 94-98%; however, estimated conditional survival in survivors aged above 18 years is 60% at 40 years of age. Atrial arrhythmias and heart failure are the leading causes of morbidity and mortality. Hypoplastic left heart syndrome, hepatic dysfunction, decreased exercise tolerance, lower quality of life, and markers of neurohormonal activation have been associated with worse outcome. Improvements in exercise tolerance are seen with selective pulmonary vasodilator therapy and exercise training. Heart transplant continues to be an effective therapy for end-stage Fontan failure, and reports of the use of traditional mechanical assist devices and the development of right heart assist devices in the setting of passive venous flow are ongoing.
Summary: Over a generation has passed since the Fontan procedure revolutionized the care of patients with a single ventricle. Data generated from retrospective and prospective observational studies in long-term survivors are identifying patients at risk.