Fontan operation in five hundred consecutive patients: factors influencing early and late outcome.

The purpose of this study was to review a large, evolving, single-center experience with the Fontan operation and to determine risk factors influencing early and late outcome. The first 500 patients undergoing modifications of the Fontan operation at our institution were identified. Perioperative variables were recorded and a cross-sectional review of survivors was undertaken. The incidence of early failure decreased from 27.1% in the first quartile of the experience to 7.5% in the last quartile. In a multivariate model, the following variables were associated with an increased probability of early failure: a mean preoperative pulmonary artery pressure of 19 mm Hg or more (p < 0.001), younger age at operation (p = 0.001), heterotaxy syndrome (p = 0.03), a right-sided tricuspid valve as the only systemic atrioventricular valve (p = 0.001), pulmonary artery distortion (p = 0.04), an atriopulmonary connection originating at the right atrial body or appendage (p = 0.001), the absence of a baffle fenestration (p = 0.002), and longer cardiopulmonary bypass time (p = 0.001). An increased probability of late failure was associated with the presence of a pacemaker before the Fontan operation (p < 0.001). A morphologically left ventricle with normally related great arteries or a single right ventricle (excluding heterotaxy syndrome and hypoplastic left heart syndrome) were associated with a decreased probability of late failure (p = 0.003). These analyses indicate that early failure has declined over the study period and that this decline is related in part to procedural modifications. A continuing late hazard phase is associated with few patient-related variables and does not appear related to procedural variables.