Medical management of the failing Fontan.

The Fontan operation accomplishes complete separation of systemic venous blood from pulmonary venous circulation in patients with single ventricle anatomy. Operative survival since the first description of the Fontan operation is excellent in the current era through modifications in surgical techniques, identification of patient-specific risk factors, and advances in postoperative care. Improved early outcomes have also resulted in a decline in late mortality for patients who have undergone staged palliation with the Fontan operation. As the number of late survivors from the Fontan operation increases, caregivers will be evermore faced with the challenge of recognizing and managing the patient with failing Fontan physiology. Even after excellent early results, patients with single ventricle lesions remain at risk of progressive ventricular dysfunction, dysrhythmias, progressive hypoxemia, elevated pulmonary vascular resistance, and protein-losing enteropathy, which can result in morbidities including but not limited to, myocardial failure, thromboembolism, and stroke. Consequently, continued long-term survival of patients who undergo the Fontan operation is dependent upon preservation of single ventricle function, avoidance of late complications, and, in the patient with a failing Fontan, recognition and treatment of the underlying pathophysiologic process that has resulted in Fontan failure.