Early Versus Late Catheter Ablation of Atrial Fibrillation and Risk of Permanent Pacemaker Implantation in Patients With Underlying Sinus Node Dysfunction.

Background Atrial fibrillation (AF) is associated with anatomical and electrical remodeling. Some patients with AF have concomitant sick sinus syndrome and may need permanent pacemaker (PPM) implantation. Association between catheter ablation of AF timing and need for PPM in sick sinus syndrome has not been assessed. Methods and Results We used pooled electronic health data to perform retrospective cross-sectional analysis of 66,  595 patients with AF and sick sinus syndrome to assess the need of PPM implantation temporally, with AF performed divided into earlier within 5 years (group 1), 5 to 10 years (group 2), or beyond 10 years (group 3) of diagnosis. PPM implantation was lowest among those who had catheter ablation within 5 years of sick sinus syndrome diagnosis: group 1 versus group 2 (18.15% versus 27.21%) and group 1 versus group 3 (18.15% versus 27.22%). Interestingly, there was no difference in risk of PPM between group 2 and group 3 (27.21% versus 27.22%; odds ratio [OR], 1.00 [95% CI, 0.85-1.20]). Conclusions Even after controlling known risk factors that increase the need for pacemaker implantation, timing of AF ablation was the strongest predictor for need for PPM. Patients adjusted OR of PPM was lower if patients had catheter ablation within 5 years of diagnosis compared with later than 5 years (adjusted OR, 0.64 [95% CI, 0.59-0.70]).