Predictors and clinical impact of intraoperative coronary sinus triggers in patients with paroxysmal atrial fibrillation undergoing radiofrequency catheter ablation

Aim This study aims to investigate the incidence and clinical impact of intraoperative coronary sinus (CS) triggers in patients with paroxysmal atrial fibrillation (PAF) undergoing radiofrequency catheter ablation. Methods Patients with symptomatic drug-refractory PAF who underwent index catheter ablation were enrolled. Patients were assigned into either the CS trigger group or pulmonary vein (PV) trigger group based on the results of electrophysiological studies of induced AF trigger. Any documented atrial tachyarrhythmia lasting ≥30 s after a 3-month blanking period, without any anti-arrhythmic drugs during post-ablation follow-up was defined as recurrence. Results The incidence of CS triggers among patients undergoing index ablation for PAF was 5.3%. Patients in the CS trigger group were younger (53.0 ± 11.8 vs. 60.5 ± 9.0 years; P 0.01) and had a smaller left atrial diameter (LAD) (36.8 ± 4.0 vs. 38.7 ± 3.8 mm; P = 0.05) than those in the PV trigger group. Age odds ratio [OR 0.93, 95% confidence interval CI 0.89–0.98; P 0.01] and LAD (OR 0.88, 95% CI 0.77–1.00; P = 0.05) were identified as independent predictors of CS triggers. Over a mean follow-up period of 13.7 ± 8.3 months, there was no significant difference in freedom from atrial tachyarrhythmias between the CS trigger and the PV trigger groups (76.5% vs. 84.2%; log-rank P = 0.50). Conclusion CS triggers are most commonly observed in relatively younger patients with a smaller LAD. The presence of a CS trigger does not adversely affect post-ablation rhythm outcomes when CS trigger ablation is incorporated into PAF management.