Procedural and Clinical Outcomes of Very High-Power Short-Duration versus Ablation Index-Guided Pulmonary Vein Isolation: The Q-POWER Study

Background Very high-power short-duration (vHPSD) ablation with close interlesion distance (ILD) strategy may improve procedural efficiency of pulmonary vein isolation (PVI) compared with ablation-index (AI)-guided ablation. Objective To compare procedural efficiency and one-year outcomes of vHPSD versus AI-guided radiofrequency (RF) PVI in patients with atrial fibrillation (AF). Methods AF patients undergoing first-time RF PVI using vHPSD (n=40, 65% paroxysmal AF, 90W/4s, ILD<4 mm) were compared with an AI-guided cohort (n=43, 74% paroxysmal AF, 30-40W, AI targets of 380-500, ILD<6 mm). In the absence of first-pass isolation (FPI), touch-up ablation (<50W) was mandatory. Following a 30-minute waiting period, bidirectional block was confirmed and acute reconnections were re-ablated. Atrial tachyarrhythmia recurrence (≥30s) was assessed over 12 months using ECG, mobile one-lead ECG monitoring, and Holter recordings. Results Patients undergoing vHPSD had smaller 3D LA volumes than those treated with AI-guided PVI (48.5±13.5mL/m 2 vs. 60.3±19.9mL/m 2 , p=0.003). Procedure and RF times were significantly shorter with vHPSD (58.0±29.7min vs. 72.4±26.0min, p=0.02; 8.3±3.0min vs. 36.9±7.6min, p<0.001, respectively). Although FPI rates were similar, acute PV reconnection tended to occurr more often with vHPSD, mainly at the carina and left PV ridge. Ablation line length correlated with LA volume and was greater in patients without FPI. One-year freedom from atrial tachyarrhythmia was similar between vHPSD and AI (60% vs. 55.8%, log-rank p=0.96). Conclusion : PVI using vHPSD with close ILD reduced procedure and RF times but resulted in more acute PV reconnections, predominantly at the carina and left PV ridge, requiring re-ablation. One-year atrial tachyarrhythmia recurrence was similar to AI-guided ablation.