The Fontan procedure: evolution in technique; attendant imperfections and transplantation for "failure".

Application of the Fontan procedure has allowed the survival of many patients with univentricular cardiac lesions into mid adulthood. Despite its ingenious design, implementation, and thoughtful modifications, its attendant hemodynamic perturbations persist; central venous hypertension and reduced cardiac output. These aberrations in physiology have led to pernicious changes in organ function. A more thorough understanding of these derangements and attempts at Fontan revision have temporized, yet the morbidity and patient attrition persists. Mechanical assistance to normalize the circulation is being investigated and holds some promise. At present, cardiac transplantation remains the last stage of palliation for many.