[Late complications of Fontan operation].

Complex univentricular heart defects are treated with the Fontan operation that consists in the diversion of the systemic venous return to the pulmonary arteries. Currently, the operation is achieved through a staged approach and with the use of prosthetic extracardiac conduits to connect the inferior vena cava to the pulmonary arteries. The improvement of early and late survival allowed these patients to reach adulthood, although long-term complications remain a relevant problem. Most of the complications are caused by chronic systemic venous hypertension due to the lack of a pumping sub-pulmonary ventricle. The most frequent complications are arrhythmias, thromboembolism, protein-losing enteropathy, heart failure and plastic bronchitis. The pathogenetic mechanisms are not completely understood but they are all connected to chronic systemic venous hypertension. Quality of life and life expectancy are deeply impaired by the onset of such complications and then a strict follow-up is required to recognize early sings of complications and to start early treatment. The creation of a highly specialized referral center network for the treatment of such complications and delicate patients is needed to improve the efficacy and the outcomes for the Fontan patients.