Abstract:

Introduction
Persistent, shock-resistant atrial fibrillation (AF) is a challenging entity with modest results from catheter ablation using conventional survival analysis. The aim of this study was to determine the effect of catheter ablation on atrial tachyarrhythmia (ATA) burden in persistent AF patients undergoing first-time ablation using an insertable cardiac monitor (ICM).

Methods
Patients with drug-resistant, ongoing persistent AF and at least one prior failed cardioversion were implanted with an ICM 2-months prior to procedure. All patients underwent pulmonary vein isolation ± additional substrate ablation depending on the presence of self-terminating AF on ICM and LA size. Median AF burden before and after ablation, off anti-arrhythmic medication, was determined from ICM recordings after review by two independent investigators.

Results
Sixty patients were recruited (66 ± 9 years, 70% male). LA diameter was 48±6 mm and median CHA2DS2VASc was 2. Ten (17%) patients unexpectedly demonstrated self-terminating AF pre-ablation. The median burden of ATA pre-ablation was 100% (P5-P95; 19.6-100%) reducing to 0% (P5-P95; 0-95.8%) post-ablation, throughout the post-blanking follow-up period (median reduction; 100%, P5-95; 4-100%, P<0.001). Twenty-seven (45%) patients experienced recurrent ATA during 12-month follow-up. In these patients, median burden pre-ablation was 100% (P5-P95; 26.9-100%) reducing to 11.4% (P5-P95;0.35-99.7%) post-ablation (P< 0.001). Quality of life improved significantly from baseline, driven by lack of recurrence.

Conclusion
Patient-tailored catheter ablation results in a significant reduction in ATA burden (off anti-arrhythmic medication) in shock-resistant, persistent AF patients, using ICMs implanted 2-months pre-procedure. These data suggest that conventional, arrhythmia-free survival analysis does not capture the true impact of catheter ablation in this challenging cohort.

Editor-in-Chief

Kalyanam Shivkumar, MD, PhD, FACC 

CME Editor
Kenneth A. Ellenbogen, MD, FACC

Author
Mahmoud Houmsse, MD, FACC 

Important Dates
Date of Release: October 23, 2023
Term of Approval/Date of CME/MOC Expiration: October 22, 2024