Clinical outcome of patients 20 years after Fontan operation — effect of fenestration on late morbidity

Objective: The Fontan operation has been proposed as definitive palliation for an increasing variety of hearts with complex univentricular anatomy, but late morbidity after Fontan operation is still a matter of concern. This retrospective study evaluates the late outcome in patients with Fontan circulation. Methods: We included 121 consecutive patients that underwent Fontan operation between 1984 and 2004. Modifications of the Fontan operation included atriopulmonary anastomosis (APA; n = 28), total cavopulmonary connection (TCPC; n = 63), and fenestrated TCPC (f-TCPC; n = 30). Mean age was 5.8 ± 5.5 years. Post operative mortality, morbidity, hemodynamics, and somatic development were analyzed. Results: Actuarial survival was 87% at 20 years after Fontan operation. There were 10 early deaths, 5 late deaths, and 2 takedowns followed by successful conversion and heart transplantation. Among 108 early-survivors with Fontan circulation, 19 underwent reoperation, including 3 conversions of APA to TCPC. Freedom from reoperation was 76% at 20 years. Freedom from intervention was 34% at 20 years. Freedom from tachyarrhythmia or pacemaker implantation was 23% and 77%, respectively at 20 years. Heterotaxy and atrioventricular valve anomaly were risk factors for late failure and tachyarrhythmias. Patients with fenestrated TCPC had reduced incidence of late tachyarrhythmias, and patients with APA who developed collaterals showed low incidence of late tachyarrythmia. Postoperative sinus node dysfunction or tachyarrhythmias was associated with significantly lower cardiac index. Somatic development was gradually compensated after Fontan operation. Weight normalized completely 15 years postoperatively. Conclusions: Long-term survival after Fontan procedure is encouraging, but late morbidity remains suboptimal. During follow-up, emerging complications should be managed by surgical and interventional procedures. Fenestration in Fontan circulation provided better cardiac output and lower incidence of late tachyarrhythmias, suggesting a benefit of fenestration for late outcome.