P6603Impact of paroxysmal atrial fibrillation ablation on cardiac sympathetic nervous system: a prospective randomized comparative study with cryoballoon catheter or radiofrequency ablation catheter

Abstract

Background: Catheter ablation of atrial fibrillation (AF) might influence the cardiac sympathetic nervous system (CSNS). We soughtto prospectively investigate the impact of AF ablation with 2nd generation cryoballoon catheter (CB) and contact force sensing radiofrequency ablation catheter (RF) on CSNS and the association of this effect with AF recurrence in patients without chronic heart failure (CHF), using cardiac iodine‐123‐metaiodobenzylguanidine (MIBG) scintigraphy. Methods and results: Seventy consecutive patients (median age 72 (66‐76) years; male, 57%) with paroxysmal AF and without CHF who were scheduled for ablation were enrolled. All patients were randomized to CB or RF (CB group; n=35, RF group; n=35). Cardiac MIBG scintigraphy was performed at baseline and 3 months post‐ablation. The heart‐to‐mediastinum ratio of 123I‐MIBG up‐take at 20 min (H/M(e)) and 200 min (H/M(d)), as well as the washout rate (WR) were measured. There were no significant differences in baseline clinical char‐acteristics such as age, gender, left atrial diameter, left ventricular ejection frac‐tion, or MIBG parameters between CB and RF groups. Although there were no significant changes in H/M(e) between CB and RF groups, H/M(d) significantly more decreased in CB group (2.15±0.37 to 2.06±0.37, p=0.042) but not in RF group (2.00±0.33 to 2.05±0.32, p=0.35). WR significantly more increased in CB group (23.0±13.1% to 27.2±13.2%, p=0.018) but not in RF group (23.5±14.0 to 24.2±14.8, p=0.75). In the blanking period of 3 months after ablation, early AF recurrence (EAR) was observed in 17 (24%) patients with no antiarrhythmic drugs (CB group vs RF group; 26% vs 23%, p=0.78). WR change from the baseline to 3 months after (dWR) was significantly greater in patients with than without EAR (12.6±11.1% vs 1.2±7.6%, p=0.0034) in CB group but not in RF group, while there was no significant difference in the H/M(d) change between them. Higher dWR (>7.7% (AUC 0.833) by ROC curve analysis) was independently associated with EAR (adjusted odds ratio =54.9, 95% CI (2.45‐1233), p=0.012) in CB group. [Figure Presented] Conclusions: Cryoballoon ablation might induce more excessive adrenergictone than radiofrequency ablation, which might be associated with early AF recurrence. Funding Acknowledgements: Osaka Heart Club.