High-Power Short-Duration vs Low-Power Long-Duration Ablation for Pulmonary Vein Isolation: A Substudy of the AWARE Randomized Controlled Trial

Background Pulmonary vein isolations (PVI) are being performed using a high-power, short duration (HPSD) strategy. The purpose of this study was to compare the clinical efficacy and safety outcomes of a HPSD vs low-power long duration (LPLD) approach to PVI in patients with paroxysmal atrial fibrillation (AF). Methods Patients were grouped according to a HPSD (≥40 W) or LPLD (≤ 35 W) strategy. The primary endpoint was the one-year recurrence of any atrial arrhythmia lasting ≥ 30 seconds, detected using three 14-day ambulatory continuous ECG monitoring. Procedural and safety endpoints were also evaluated. The primary analysis were regression models incorporating propensity scores yielding adjusted relative risk (RRa) and mean difference (MDa) estimates. Results Of the 398 patients included in the AWARE Trial, 173 (43%) underwent HPSD and 225 (57%) LPLD ablation. The distribution of power was 50 W in 75%, 45 W in 20% and 40 W in 5% in the HPSD group, and 35W with 25W on the posterior wall in the LPLD group. The primary outcome was not statistically significant at 30.1% vs 22.2% in HPSD and LPLD group with RRa 0.77 (95% confidence interval [CI]) 0.55-1.10; p=0.165). The secondary outcome of repeat catheter ablation was not statistically significant at 6.9% and 9.8% (RRa 1.59 [95% CI 0.77-3.30]; p=0.208) respectively. The incidence of any ECG documented AF during the blanking period was numerically lower in the HPSD group: 1.7% vs 8.0% (RRa 3.95 [95% CI 1.00-15.61; p=0.049). The total procedure time was significantly shorter in the HPSD group (MDa 97.5 minutes [95% CI 84.8-110.4)]; p<0.0001) with no difference in adjudicated serious adverse events. Conclusions A HPSD strategy was associated with significantly shorter procedural times with similar efficacy in terms of clinical arrhythmia recurrence. Importantly, there was no signal for increased harm with a HPSD strategy. ![Figure][1] Non-standard Abbreviations and Acronyms HPSD: High-Power Short Duration; LPLD: Low-Power Long Duration; QOL: Quality of Life; WACA: wide area circumferential ablation; PVI: Pulmonary Vein Isolation; AF: Atrial Fibrillation What is known -The optimal power and duration of ablation lesions to produce durable pulmonary vein isolation remain unclear. -Nonrandomized studies have suggested clinical efficacy with high-power short duration radiofrequency ablation vs low-power long duration. What this study adds -In this large substudy of the AWARE Trial, a high-power short duration radiofrequency ablation strategy was found to be similarly effective as a low-power long duration strategy with no difference in time to first recurrence of any AF lasting ≥ 30 seconds. -Procedural were substantially reduced with high-power short duration ablation with no significant difference in overall complication rates. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial NCT02150902 ### Funding Statement The AWARE RCT was funded by grants from the Canadian Institutes of Health Research, the University of Ottawa Heart Institute, Division of Cardiology and Academic Medical Organization, and by an unrestricted research grant from Biosense Webster (IIS-381) ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics Approval was obtained from the Ottawa Heart Research Institute and each separate hospital local ethics board. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as [ClinicalTrials.gov][2]. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data is available upon request [1]: pending:yes [2]: http://ClinicalTrials.gov