Abstract 11683: Recurrence of Atrial Arrhythmias Following Ablation in Adults With Congenital Heart Disease: New Substrate Formation or Late Procedural Failure?
Introduction: Using current mapping and ablation tools, high acute success rates can be achieved in repaired adult congenital heart disease (CHD) patients with atrial arrhythmias, but recurrences are common. We examined the nature of recurrence in a cohort of repaired adult CHD patients.
Hypothesis: We tested the hypothesis that recurrences after ablation in repaired CHD patients represent the development of new substrates.
Methods: A retrospective chart review was performed on all repaired adult CHD patients undergoing ablation for atrial arrhythmias, excluding atrial fibrillation (AF), at our institution from Jan. 2003-Nov. 2013. CHD lesions were grouped as tetralogy-type, atrial switch, single ventricle, and other. Latest follow-up data were obtained on all patients. Acute procedural success was defined as ablation of all targeted circuits. All recurrences warranting clinical intervention were noted.
Results: A total of 118 patients underwent 157 ablation procedures, and 253 tachycardias were targeted. Of these, 99 utilized the cavo-tricuspid isthmus (CTI), 88 were non-isthmus-dependent scar-related macro-reentry, 55 were focal tachycardias, and 13 were atrioventricular reciprocating tachycardias. Acute procedural success was obtained in 147/157 (94%) procedures and 237/253 (94%) targeted arrhythmias. Recurrence was observed after 78 (50%) procedures after a median time of 6 months. Of those undergoing repeat ablations, new substrates were found to be the cause of recurrence in 18 (23%), while recurrence of the original substrate was documented in 20 (26%). AF accounted for 9 (12%) of the recurrences. By lesion type, recurrence was most common among single ventricle patients (81% vs. all others 42%, p <0.001).By substrate, recurrence was lowest with CTI-dependent circuits (35% vs. all others 56%, p=0.016).
Conclusions: Despite high acute procedural success rates, patients with repaired CHD had frequent recurrence of atrial arrhythmias. These represented both new substrates, including the development of AF, and recurrence of previously-ablated substrates with a similar frequency. Repeat ablation may be warranted in those with recurrences as a new target for ablation may be identified.
Author Disclosures: J. Shuplock: None. G. Barker: None. A. Radbill: None. P. Kannankeril: None. F.A. Fish: Consultant/Advisory Board; Modest; Biosense Webster, Inc..
- © 2014 by American Heart Association, Inc.