Long-Term Outcomes After Fontan Conversion Operation: A Comparative Analysis Based on Type of Fontan Connection

BACKGROUND: Fontan conversion (FC) is associated with a lower risk of atrial arrhythmias and thromboembolism, but it is unknown whether FC improves long-term survival. The purpose of this study was to assess the impact of FC on transplant-free survival. METHOD: Adults with Fontan palliation were divided into 3 groups: (1) atriopulmonary Fontan connection; (2) atriopulmonary Fontan and subsequent FC to total cavopulmonary connection (TCPC); (3) TCPC at initial Fontan operation. The risk of death/transplant was compared between the 3 groups using Cox regression analysis. RESULTS: We studied 534 patients (age 27±9 years; males N=298; 56%). Patients were divided into atriopulmonary Fontan group (N=199, 37%); FC-TCPC (N=138, 26%); and TCPC (N=197, 37%). The FC-TCPC and TCPC groups have similar 15-year incidence of death/transplant (42% versus 47%; P =0.8), even after excluding the 8% operative mortality in the FC-TCPC group (38% versus 47%; P =0.3). On multivariable analyses, neither FC nor the type of Fontan connection was associated with death/transplant. Rather, the risk factors for death/transplant were older age, hepatorenal dysfunction, heart failure, and higher Fontan pressures. The prevalence and severity of these comorbidities increased with age, suggesting that these factors reflect the duration of Fontan physiology, rather than the type of Fontan connection. CONCLUSIONS: These findings, in addition to the high operative mortality associated with FC, suggest that this may not be the optimal treatment option for most adults with atriopulmonary Fontan presenting with Fontan failure. Duration of Fontan physiology rather than the type of Fontan connection may be the main determinant of outcomes.