Fontan Operation After 3 Decades: What We Have Learned

W. M. Gersony
2008 Circulation  
T he Fontan operation was designed to provide blood flow in series to the pulmonary and systemic circulation without the requirement for a right ventricular pumping chamber. The operation allows systemic venous blood to flow directly into the pulmonary circulation on the basis of a single ventricular impetus through the arteries, capillaries, and systemic venous system. This arrangement has improved life expectancy for patients with single-ventricle and pulmonaryoutflow obstruction compared
more » ... previous arterial shunts. The long-term effects of marked single-ventricle preload and inefficient oxygenation via an arterial shunt rarely allowed survival beyond the second or third decade of life. Remarkably, the Fontan operation has become the most common procedure performed for congenital heart disease after the age of 2 years. Over the past 3 decades, the early and intermediate prognoses for patients who have undergone this operation have been improving as a result of useful refinements in the surgical procedure that have been introduced since Fontan's original direct right atrium-to-pulmonary artery (RA-PA) connection. Furthermore, the indications for the operation have broadened considerably compared with the relatively few patients thought to be eligible in the late 1970s and 1980s. Article p 85 The ultimate test of any surgical procedure is the long-term status of the postoperative patients. The article by Khairy and associates 1 in this issue of Circulation provides insight into the survival of the earliest generation of Fontan patients and allows assessment of the impact of management and surgical variations that have evolved over the past 3 decades on mortality. However, the young adults reported in this study represent the survivors of the early operations and may not reflect the eventual status of today's infants and children who undergo the modern procedure. Beyond mortality, it is important to evaluate potential risk factors as they relate to the functional status and quality of life of patients with a Fontan circulation. A recent survey of young children and adolescents who have undergone the Fontan operation attempts to address this issue. 2,3 If the factors that lead to a failed Fontan in terms of mortality, current medical status, and quality of life can be understood, it is hoped that the next decade will allow further improvements in the management of patients with a single ventricle. Mortality Perioperative and early mortality after the Fontan operation have decreased markedly over the past 3 decades. Among early survivors, late mortality and modes of death can be assessed with the notion that predictors of intermediate or late mortality can be uncovered. In the report by Khairy et al, 1 82.6% of the early survivors were alive and had not had a cardiac transplant 15 to 20 years later. It is of interest that this study found no significant difference in life expectancy beyond the postoperative period between the more obsolete, less efficient RA-PA connections and the direct caval-pulmonary artery connections. Among long-term survivors, the data from this series indicated that the 3 most common causes of late death were thromboembolism, heart failure, and sudden death. Thromboembolic late death was found to be more common than previously documented. 4 The predictors of thromboembolic death by multivariate analysis were lack of aspirin/ warfarin therapy and intracardiac thrombus. Five of the 6 deaths were in patients who had direct RA-PA connections, which perhaps indicates the modern total cavopulmonary connections are less likely to be associated with thromboembolism; however, less follow-up time is available for the latter group of patients. The higher risk for heart failure related to the presence of a single morphological right as opposed to left ventricle is consistent with other studies that indicate the same trend. 2, 3, 5, 6 This result is to be expected given that the right ventricle is not geometrically suited to be a systemic ventricle. The differences at intermediate follow-up, although significant, are not great between the 2 types of morphological single ventricle, but over the next 15 or 20 years, they are likely to become more prominent. High right atrial pressures and protein-losing enteropathy are well-established risk factors for heart failure. Sudden deaths were more common earlier after Fontan surgery. Almost all occurred within the first 5 years, were presumed to be related to cardiac arrhythmias, and were not associated with any potential risk factor. Khairy et al 1 have provided excellent data on mortality in the early Fontan patients after 15 to 20 years. The question remains as to the fate of the more modern single-ventricle patients who have undergone the Fontan operation. The majority of present-day patients have hypoplastic left heart syndrome, which indicates that they will be at higher risk
doi:10.1161/circulationaha.107.748566 pmid:18172049 fatcat:t6xklf25zzgqveufksnljdj6ru