Lower atrial fibrillation recurrence after ablation in general anesthesia - a danish nationwide registry study
Authors: Riis-Vestergaard L , Toennesen J , Pallisgard J , Rasmussen P , Ruwald M , Zoerner C , Middelfart C , Gislason G , Hansen M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public hospital(s). Main funding source(s): Copenhagen Cardiovascular Research Center, Department of Cardiology, Copenhagen University Hospital Herlev and Gentofte, Denmark

Introduction
Atrial fibrillation (AF) is the most frequent cardiac arrythmia worldwide with increasing incidence and prevalence. Treatment with catheter ablation (CA) as rhythm control is more frequently used. Studies comparing different ablation methods and strategies, have not found any significant difference in durability and effect on AF recurrence. Whether use of conscious sedation (CS) or general anesthesia (GA) has any impact on AF recurrence, has yet to be determined. There is currently no general recommendation on sedation strategy for CA.

Purpose
To examine AF recurrence by CS or GA in CA.

Method
This nationwide retrospective registry study was conducted using large real-life data from Danish mandatory registries. All patients above 18 years of age, that underwent first-time CA for AF from January 1st 2010 to December 31st 2018, were identified and included at the date of ablation. Exposure of interest was type of anesthesia, and patients were stratified into CS or GA. Primary endpoint was recurrent AF after a 3-months blanking period, defined by a composite endpoint of first-reached endpoint of either use of antiarrhythmic drugs (AAD), AF-admission, electrical cardioversions or AF re-ablation. 5-year risk of recurrent AF was examined by the Aalen-Johansen estimator, taking the competing risk of death into account. The relative rates of recurrent AF by anesthesia type were examined by Cox proportional models using GA as refence. The analysis was adjusted for clinically important baseline characteristics including age, sex, diagnosis-to-ablation time, procedural year, body mass index, size of left atrium, parixysmal/persistent AF, heart failure, ischemic heart disease, chronic obstructive pulmonary disease, chronic kidney disease, hypertension and diabetes.

Results
The study cohort consisted of 7,889 patients, of which 6,402 underwent ablation in CS and 1,487 underwent ablation in GA. A total of 4,167 patients reached the primary endpoint. Admissions for AF was the predominant endpoint (2172, 52,1%) followed by use of AAD (993, 23,8%) and electrical cardioversion (684, 16,4%). 5-year cumulative incidence of recurrent AF was higher in the CS group with 53,9%, compared to 43,2% in the GA group (Figure 1). Multivariate cox proportional-hazard model showed increased hazard ratio of 1.26 (95% CI: 1.15 – 1.39) for the CS group compared to the GA group (Figure 2).

Conclusion
Small marginals are chased in optimizing outcome after AF ablation. Ablation method and strategy has yet to find significantly improvements in large cohorts and in long-term follow up. In this large nationwide study we found, that the risk of AF recurrence was markedly reduced with CA performed in GA compared to CS. Knowledge from this study suggests, GA could be the most preferable sedation strategy for CA.