Background: Radiofrequency (RF) lesion formation depends on RF power and ablation duration as well as contact force (CF). Although increased RF power can create more continuous and transmural lesion, most of centers still use power of 25-30 W for durations of 30-40 seconds at each ablation point because of safety concern about using higher power (HP)
Objective: We evaluated the clinical efficacy and safety of HP application with short duration (HPSD) for atrial fibrillation (AF) ablation
Methods: One hundred fifty patients (58.2±10.0 years, 48% in paroxysmal AF [PAF]) scheduled for index AF ablation using a CF-sensing catheter were randomly assigned to 3 groups (30W/40sec, 40W/20sec, and 50W/10sec at ablation sites of left atrial [LA] anterior wall and roof line)
. 25-30 W for ≤20sec was applied at posterior wall ablation site in all subjects
Results: Compared with 30W/40sec and 40W/20sec groups, 50W/10sec group had shorter procedure time (p<0.001), ablation time (p<0.001), and fluoroscopy time (p=0.001). There were no significant differences in CF and ablation index (AI) among 3 groups. In each group, AI increased proportionally as CF increased. There were no significant differences in procedure-related complications. During a 12-month follow-up period, AF recurrence occurred in 24 (16%) patients and revealed no significant difference among 3 groups (p=0.769). In multivariate analysis, non-PAF (HR 2.912, 95% CI 1.045-8.119, p=0.041) and CF (HR 0.736, 95% CI 0.628-0.863, p<0.001) were independent risk factors for AF recurrence
Conclusion: RF ablation with HPSD limited to LA anterior wall and roof line is a safe and effective strategy with reduced procedure, ablation, and fluoroscopy times
Procedural data
| Overall (n=150) | 30W/40sec (n=50) | 40W/20sec (n=50) | 50W/10sec (n=50) | P-value |
| Procedure time, min | 135.4±37.5 | 161.9±37.9 | 135.6±29.5 | 108.7±23.1 | <0.001 |
| Ablation time, min | 75.2±26.8 | 93.1±30.5 | 72.3±21.5 | 60.2±14.7 | <0.001 |
| Fluoroscopy time, min | 11.1±3.8 | 12.5±3.6 | 11.0±3.0 | 9.7±4.1 | 0.001 |
| Contact force, g | 12.1.1±3.4 | 12.1±4.0 | 12.2±2.9 | 12.1±3.3 | 0.979 |
| Ablation duration/point, sec | 17.7±7.2 | 25.7±4.7 | 15.9±3.5 | 11.6±3.9 | <0.001 |
| Force time integral, gs | 222.3±120.6 | 318.2±129.0 | 200.5±74.5 | 148.1±81.0 | <0.001 |
| Force time power integral, gsw | 8252.9±3751.6 | 9495.9±3869.4 | 7949.9±2979.3 | 7312.9±4047.8 | 0.011 |
| Ablation index | 445.5±46.5 | 452.8±49.6 | 447.7±44.5 | 435.9±46.5 | 0.184 |
| Additional LA ablation | 31 (20.7) | 12 (24.0) | 11 (22.0) | 8 (16.0) | 0.589 |
