Noncontact mapping identified exit sites in all 11 arrhythmias across 6 Fontan patients, guiding ablation that achieved immediate success in 3 of 5 RF patients, with 2 recurrences at 6.4 months.
Observational (n=6)
BACKGROUND: Atrial tachyarrhythmias are a complication of Fontan surgery. Conventional electrophysiological mapping and ablation techniques are limited by the complex anatomic and surgical substrate and a high arrhythmia recurrence rate. This study investigates the use of noncontact mapping to identify arrhythmia circuits and guide ablation in Fontan patients. METHODS AND RESULTS: Eleven arrhythmias were recorded in 6 patients. Noncontact mapping improved recognition of the anatomic and surgical substrate and identified exit sites from zones of slow conduction in all clinical arrhythmias. Radiofrequency linear lesions were targeted across these critical zones in 5 patients. One patient underwent surgical cryotherapy. Although immediate success was achieved in 3 of 5 patients with radiofrequency ablation, 2 patients had a recurrence after a mean of 6.4 months of follow-up. The patient who underwent cryoablation remains free of arrhythmias. CONCLUSIONS: Noncontact mapping can identify arrhythmia circuits in the Fontan atrium and guide placement of ablation lesions. Arrhythmia recurrence is high, possibly because of inadequate lesion creation rather than inaccurate mapping and lesion targeting.
Betts et al. (Tue,) conducted a observational in Intra-atrial reentry tachycardia after Fontan surgery (n=6). Noncontact mapping and ablation was evaluated on Identification of exit sites from zones of slow conduction. Noncontact mapping identified exit sites in all 11 arrhythmias across 6 Fontan patients, guiding ablation that achieved immediate success in 3 of 5 RF patients, with 2 recurrences at 6.4 months.