Long-Term Follow-Up of Radiofrequency Slow Pathway Ablation for Atrioventricular Nodal Re-Entrant Tachycardia: Late Outcomes.

INTRODUCTION

Slow pathway radiofrequency ablation is an effective treatment for atrioventricular nodal re-entrant tachycardia (AVNRT) but has been reported in some series to result in late atrioventricular block. We examined our local experience with a retrospective review.

METHODS

A retrospective review of all patients undergoing slow pathway ablation at our institution from 1993 through to 2021 was undertaken, with long-term outcomes reported till the end of 2022. Outcomes assessed included late atrioventricular block, and rhythm control.

RESULTS

We identified a total of 1290 procedures performed on 1256 patients over the 28-year period. Mean patient age at the time of the procedure was 48.5 years (range 13 to 93 years). A total of 1234 patients were followed up, whilst 22 were lost to follow-up. Mean follow up was 12.6 years (range 1 to 29 years). Of this cohort 9 patients subsequently developed atrioventricular block and proceeded to pacemaker implantation, for an incidence of 0.58 per 1000 patient years. Overall long-term rhythm controlled was achieved in 1221 (97%) patients.

CONCLUSIONS

We report what we believe to be the largest single centre experience, with the longest follow-up for slow pathway ablation, for AVNRT. We observed a low rate of late atrioventricular block that was not clearly higher than the spontaneous rate of heart block, yet still achieving good rhythm control. We believe our data supports radiofrequency slow pathway modification as effective and safe therapy for atrioventricular nodal re-entrant tachycardia.