Preliminary analysis of arrhythmias after the Fontan operation with extracardiac conduit compared with intra-atrial lateral tunnel

Background: It is to be expected that avoidance of the atrial suture line during extracardiac Fontan operation (ECFO) decreases the risk of postoperative arrhythmias. Methods: Two groups of consecutive patients (23 with lateral tunnel (LTFO) and 24 with extracardiac conduit) who underwent successful Fontan operations between 5/93 and 10/98 were comparatively analyzed. All patients had postoperatively standard ECG and 24-hour monitoring. During follow-up, all patients had 2 - 8 (mean 3) standard ECG recordings per year and 76% of the patients a 24-hour Holter ECG once a year. Results: Median follow-up after ECFO and LTFO was 2.4 years and 4.5 years, respectively. The incidence of supraventricular tachyarrhythmias and bradyarrhythmias after ECFO versus LTFO was lower early after operation and during follow-up (p < 0.05). in follow-up, 20 ECFO patients (91%) versus 11 patients after LTFO (52%) remained in sinus rhythm (p<0.01). Pacemaker insertion was required in 7 (33%) LTFO patients but none of the ECFO patients (p < 0.01). Conclusions: The extracardiac Fontan operation decreases the incidence of early and medium-term postoperative arrhythmias. Comparative long-term results are not yet available.