Arrhythmias after Fontan operation: comparison of lateral tunnel and extracardiac conduit

Arrhythmias are frequent causes of morbidity and mortality in patients with single ventricle physiology after Fontan operation. The aim of this study was to evaluate which type of Fontan procedure--lateral tunnel (LT) or extracardiac conduit (EC)--provides superior outcomes related to the problem of early postoperative and 1-year follow-up arrhythmias.

We retrospectively analyzed the incidence, types, and duration of rhythm disorders in 101 consecutive patients who received either LT (n = 60) or EC (n = 41) between April 1997 and March 2006 in Slovak Children's Cardiac Center, Bratislava (Slovakia). Weight, age, sex, and the type of heart morphology did not differ significantly between the 2 groups. The rhythm was monitored and documented perioperatively and postoperatively with standard electrocardiogram (ECG) recording and continual ECG monitoring. Duration of extracorporeal circulation, duration of aortic crossclamp and hemodynamic variables were analyzed with respect to the development of early arrhythmias in both groups. Twenty-four-hour ECG Holter monitoring (DMS 300-7, Holterreader, Producer DMS, Nevada, USA) was used to detect arrhythmias at the 1-year follow-up.

Early postoperative rhythm abnormalities were identified in 31 patients (52%) who underwent LT and in 22 patients (54%) who underwent EC. The most frequent type of rhythm disturbance was junctional rhythm in both groups. The bivariate analysis revealed that there was no significant difference in the incidence, type, or duration of early onset arrhythmias between the 2 groups. Although, there was no significant difference in the duration of arrhythmia since the admission form the operating room. The need of aortic crossclamp was significantly lower in EC group (P < .001). However, this did not correlate with lower incidence of early onset arrhythmias with EC modification. At the 1-year follow-up, the prevalence of arrhythmias was similar in both groups.

Extracardiac conduit as compared with LT does not provide superior outcomes related to the problem of early and 1-year onset arrhythmias. Other factors than the risk of early postoperative and early follow-up arrhythmias should be considered in surgical preference of modification strategy.