IMPROVED EARLY MORBIDITY AND MORTALITY AFTER FONTAN OPERATION - THE MAYO-CLINIC EXPERIENCE, 1987 TO 1992

Objectives. This study sought to evaluate changes in early morbidity a nd mortality as well as predictors of outcome in our most recent 339 p atients undergoing modified Fontan operations. Background. The Fontan operation is the preferred definitive palliation for patients with fun ctional single ventricles. Previously reported early mortality rates a fter Fontan operation have been substantial. Methods. Records of 339 c onsecutive patients who had a Fontan operation at the Mayo Clinic betw een 1987 and 1992 (recent cohort) were reviewed. This cohort was compa red with the previous 500 patients who had Fontan operations performed between 1973 and 1986 (early cohort). Results. Recently, overall earl y mortality after Fontan has decreased significantly compared with tha t for the early cohort (from 16% to 9%, p = 0.002). This decline occur red despite increased anatomic complexity of patients. Short-term post hospital survival has also improved significantly in recent patients. One-year survival improved to 88% from 79%, and 5-year survival to 81% from 73% (p = 0.006). Patients with common atrioventricular valves an d those who took daily preoperative diuretic medication or had either postoperative renal failure or elevated postbypass right atrial pressu re were at increased risk for early mortality. Young age was not found to be a risk factor for early mortality. Early mortality for patients with heterotaxia decreased dramatically: recent 30 day mortality was 15% compared with 41% in the early heterotaxy cohort. Conclusions. Man y factors may have contributed to decreased early mortality after Font an. Improved patient selection, younger age at time of operation, refi nements in surgical techniques and postoperative management may all ha ve had important roles. Proposed technical modifications of the Fontan operation must be evaluated in light of these improved results.