Procedural Volume and Outcomes with Atrial Fibrillation Ablation: A Report from the NCDR AFib Ablation Registry

Background: Hospital and physician procedure volumes have been associated with outcomes for several cardiac procedures however this has not been well defined for atrial fibrillation (AF) ablation in the contemporary practice. Objective: To determine the association between hospital and physician procedural volume and success for AF ablation and the risk of major adverse events (MAE). Methods: Procedures reported to the NCDR AFib Ablation Registry between July 2019 and June 2022 were included. Physician and hospital procedural volumes were annualized and stratified into quartiles (Q) to compare success and MAE. Three level hierarchical (patient, hospital and physician) generalized linear models were used to assess the adjusted relationship between procedural volume and the likelihood of procedural outcomes. Results: A total of 70,296 first time AF ablation at 186 hospitals across the United States were included. The mean age was 66.1 ± 10.3 years, 36% were women, the mean CHA2DS2-VASc score was 2.7 ± 1.6, and 57.4% of patients had paroxysmal AF. The median annual procedural volume for hospitals and physicians were 230 (IQR:144.7-307.2) and 66 (IQR: 44.7-97.5), respectively. Overall, acute procedural success was 98.5 % and the MAE rate was 1.0%. With Q4 (highest) hospital volume as a reference, the adjusted likelihood of procedural success was significantly lower for Q1 (OR: 0.44, CI: 0.29-0.68), Q2 (OR: 0.50, CI: 0.33-0.75) and Q3 (OR: 0.60, CI: 0.40-0.89). Similarly, for physician, procedural success was less among Q1 (OR: 0.38, CI: 0.28-0.51), Q2 (OR: 0.51, CI: 0.38-0.69) and Q3 (OR: 0.55, CI: 0.42-0.72). With MAE, compared with Q4, there was an inverse relationship between procedural volume for hospitals in Q1 (OR: 1.78, CI: 1.26-2.51) but not Q2 (OR: 1.06, CI: 0.77-1.46) or Q3 (OR: 1.19, CI: 0.89-1.58) and for physicians in Q1 (OR: 1.93, CI: 1.44-2.58) and Q2 (OR: 1.49, CI: 1.13-1.97) but not in Q3 (OR: 1.22, CI: 0.94-1.58). An adjusted MAE ? 1% was predicted by an annual volume of approximately 190 for hospitals and 60 for physicians. Conclusion: In this national cohort, hospital and physician AF ablation procedural volumes were directly related to acute procedural success and inversely related to rates of MAE. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was funded by the American College of Cardiology (ACC) National Cardiovascular Data Registry (NCDR). ### 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: The study was approved by Yale IRB 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. 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 The data for the study were obtained from the NCDR AF registry. Data may be made available from NCDR AF registry upon request.