Abstract 13978: Response to Isoproterenol Infusion may Predict Procedural Success Following Ablation for Atrial Fibrillation

Introduction: Atrial fibrillation (AF) trigger elimination, such as pulmonary vein (PV) isolation, is one of the major procedural endpoints in AF ablation. We have previously found that the ectopies with short coupling interval (CI) more likely initiate AF, and found that %CI Hypothesis: We hypothesized that patients who have AF-trigger ectopies have better procedural outcome than those without AF-trigger ectopies. Methods: We studied 120 consecutive patients with AF who underwent an initial ablation. Prior to ablation, AF induction was performed using isoproterenol infusion. PV isolation was performed, and non-PV trigger elimination was added if necessary. AF recurrence-free survival rates were compared between patients with the ectopies that triggered AF or had %CI Results: Identified trigger group comprised 39 (33%) patients. Patient characteristics were similar between the groups including age (67±10 vs. 67±8 years, p=0.83), persistent AF (42% vs. 44%, p=0.50) and left atrial diameter (38±9 vs. 39±6 mm, p=0.30). Of 276 ectopies provoked, 77(28%) triggered AF and 92(33%) demonstrated short CI without AF initiation. All of them were originated from PVs (92%) or superior vena cava (8%). At 11±2 months, 23 (20%) patients developed AF recurrence. Identified trigger group showed a significantly better AF recurrence-free survival rate than unknown trigger group (92% vs. 70%, p=0.033). In multivariate analysis, identified trigger was an independent predictor of AF recurrence-free survival (Adjusted Hazard ratio [95% CI] = 0.21 [0.05, 0.90] (p=0.036)). Conclusions: AF-trigger identification by isoproterenol infusion may be a useful predictor of procedural success in patients undergoing AF ablation.