Treatment strategy and endpoint of catheter ablation for bi‐atrial tachycardia after substrate modification ablation in a low voltage zone of the left atrial anterior wall: Long‐term results

Abstract

Abstract Background The termination of bi‐atrial tachycardia (BiAT) via the ablation of the Bachmann's bundle (BB) and mitral isthmus (MI) has been previously reported; however, the strategy and long‐term results of catheter ablation for BiAT remain unclear. Methods The data of nine patients with BiAT who underwent low voltage zone (LVZ) ablation of the left atrial anterior wall (LAAW) after pulmonary vein isolation were reviewed. Patients with a P wave duration 100 ms underwent BB ablation. Results MI ablation was performed in three patients and six patients underwent BB ablation. The difference in the P wave duration before and after ablation was significantly different between the ablation sites (MI group: 5.0 ms difference; BB group; 38.5 ms difference; P = .024). The P wave duration was prolonged by >20 ms and was 120 ms or more after ablation in 5/6 patients who underwent BB ablation. The total recurrence rate was 11.0% (mean: 26.9 months). Conclusion The recurrence of BiAT after MI or BB ablation is low. When BB ablation was performed, the P wave duration was prolonged by >20 ms and was at least 120 ms after the ablation, which may be an endpoint that can be used to measure the success of the ablation.

Keywords

• Bachmann's bundle
• bi‐atrial tachycardia
• catheter ablation
• mitral isthmus
• tachyarrhythmia