Ablation index-guided 50 W ablation for pulmonary vein isolation in patients with atrial fibrillation: Procedural data, lesion analysis, and initial results from the FAFA AI High Power Study

Background Radiofrequency high-power ablation appears to be a novel concept for atrial fibrillation (AF). The ablation index (AI) value has been associated with durability of pulmonary vein isolation (PVI). Objectives This study aimed to report the procedural data and initial results of a combined ablation technique using AI-guided high-power (AI-HP; 50 W) ablation for PVI. Methods Symptomatic AF patients were consecutively enrolled and underwent wide-area contiguous circumferential PVI. Contact-force catheters were used, ablation power was set to 50 W targeting AI values (550 anterior and 400 posterior). Esophageal temperature was monitored during procedure, all patients underwent postablation esophageal endoscopy. Results PVI was achieved in all (n = 50, mean age: 68 +/- 9 years, female: 60%) patients, rate of first-round PVI was 92%. A total of N = 2105 AI-guided ablation lesions were analyzed. Comparing left anterior wall vs left posterior wall and right anterior wall vs right posterior wall, mean ablation time (s) per lesion was 20.5 +/- 8 vs 8.6 +/- 3 and 12.2 +/- 4 vs 9.3 +/- 3; mean contact force (g): 17.1 +/- 12 vs 25.4 +/- 14 and 33.7 +/- 13 vs 21.0 +/- 11; mean AI: 547 +/- 48 vs 445 +/- 55 and 555 +/- 56 vs 440 +/- 47 (all P < .0001). Procedure and fluoroscopy time (minute) were 55.6 +/- 6.6 and 6 +/- 1.7, respectively. Only one (2%) patient had a minimal esophageal lesion. During In-hospital and 1-month follow-up no major complications such as death, stroke, tamponade, or atriaesophageal fistula (AE) occurred. Preliminary 6-month follow-up showed 48 of 50 (96%) patients were free from clinical AF/atrial tachycardia recurrence. Conclusion AI-HP (50 W) ablation appears to be a feasible, safe, fast, and effective ablation technique for PVI.