Catheter ablation of atrio-ventricular accessory pathways in the era of ablation therapy of complex arrhythmias: a changing perspective for oncoming generation of electrophysiologists

Overview

Introduction:
Catheter ablation of atrio-ventricular accessory pathways has become a routine treatment method. However, its perspective has been changing in the era of ablation of complex arrhythmias. This study was aimed at evaluating accessory pathways ablation efficacy within the last nine years at one center.

Methods:
From February 2002 to June 2011, catheter ablation of accessory pathways was performed in 247 patients (100 females, 42 ± 16 years). Elimination of accessory pathways conduction in both directions was the procedure endpoint.

Results:
Immediate accessory pathways conduction elimination at the first ablation was achieved in 228 (92%) patients. Ablation failed to eliminate accessory pathways conduction in 19 (8%) patients, or accessory pathways conduction subsequently recurred in another 7 (3%) patients. Repeat ablation was completed in 20 (8%) patients, 2 patients underwent a third ablation procedure. In total, accessory pathway was permanently eliminated in 238 (96%) patients. Ablation failure was connected with a risky position in the vicinity of atrio-ventricular conduction system in 6 (67 %) out of 9 patients. By the individual A, B, C, D operators’ experience, efficacy of the first procedure/total efficacy, was 97%/99%, 90%/96%, 87%/87%, and 91%/91%, respectively (comparison of inter-operator efficacy of the first and repeat ablation by Kruskal-Wallis ANOVA test: p = 0,19 and 0,05, respectively).

Conclusion:
Accessory pathways ablation efficacy exceeds 95%, and ablation failure is dominantly related to the accessory pathways location close to the atrio-ventricular conduction system. Individual operator’s experience was associated with a certain disparity between high and nearly absolute accessory pathways ablation efficacy.

Key words:
catheter ablation – accessory pathways – outcomes