Extracardiac Versus Lateral Tunnel Fontan: A Meta-Analysis of Long-Term Results

Abstract

There is growing awareness of the long-term impact of a Fontan circulation on the associated morbidity and mortality. Comparative data on the incidence of supraventricular arrhythmia and sinus node dysfunction following extracardiac conduit (EC) and lateral tunnel (LT) Fontans are controversial. We performed a meta-analysis pooling all available long-term results comparing the EC and LT Fontan, with a special focus on arrhythmia. We performed a systematic search of PubMed, Embase, and the Cochrane Library for articles reporting long-term results of Fontan comparing the EC and the LT Fontan. Twelve studies were selected with 3,330 patients (1,729 EC, 1,601 LT). Freedom from tachyarrhythmia was significantly higher in the EC group (92% versus 83% at 15 years; p < 0.0001), while there was no difference in term of bradyarrhythmias (p= 0.7). The survival was 93% and 89% at 20 years in the EC and LT groups, respectively (p= 0.007). The risk of thromboembolic events was 2.87% patient-years in the EC group versus 0.9% in the LT group (odds ratio, 2.15; 95% confidence interval, 0.95 to 4.85; p= 0.07). The EC Fontan confers long-term survival advantage over the LT Fontan without a higher rate of reoperations. The EC Fontan preserves the sinus node function and reduces significantly the incidence of long-term postoperative arrhythmia.