Survival After Surgical Ablation of Atrial Fibrillation During Coronary Artery Bypass in Medicare Beneficiaries

Justin M Schaffer; Austin Kluis; John J Squiers; Timothy J George; Emily Shih; Jasjit K Banwait; Michael J Mack; J Michael DiMaio

doi:10.1016/j.athoracsur.2025.03.044

Survival After Surgical Ablation of Atrial Fibrillation During Coronary Artery Bypass in Medicare Beneficiaries

Ann Thorac Surg. 2025 Jun 2:S0003-4975(25)00339-X. doi: 10.1016/j.athoracsur.2025.03.044. Online ahead of print.

Authors

Justin M Schaffer¹, Austin Kluis², John J Squiers², Timothy J George², Emily Shih², Jasjit K Banwait³, Michael J Mack⁴, J Michael DiMaio⁴

Affiliations

¹ Department of Cardiothoracic Surgery, Baylor Scott & White, The Heart Hospital, Plano, Texas. Electronic address: justin.schaffer@bswhealth.org.
² Department of Cardiothoracic Surgery, Baylor Scott & White, The Heart Hospital, Plano, Texas.
³ Baylor Scott & White Research Institute, Plano, Texas.
⁴ Department of Cardiothoracic Surgery, Baylor Scott & White, The Heart Hospital, Plano, Texas; Baylor Scott & White Research Institute, Plano, Texas.

PMID: 40459477
DOI: 10.1016/j.athoracsur.2025.03.044

Abstract

Background: Despite guideline recommendations, use of concomitant surgical ablation during isolated coronary artery bypass grafting (CABG) in patients with preexisting atrial fibrillation is low, with a poorly quantified impact on stroke and survival.

Methods: A retrospective review of Medicare data identified 87,699 beneficiaries with preexisting atrial fibrillation undergoing CABG, with or without concomitant surgical ablation, from 2008 to 2019. All-cause mortality and the incidence of stroke were evaluated as separate end points. Overlap propensity score weighting adjusted for measured confounding variables. Analyses were repeated using surgeon frequency of ablation as an instrumental variable to adjust for unmeasured confounding variables.

Results: Of 87,699 beneficiaries with atrial fibrillation undergoing CABG, 19,384 (22.2%) underwent concomitant surgical ablation. During CABG, 1193 surgeons infrequently performed ablation (<5%; 16,242 beneficiaries), 1834 occasionally performed ablation (≥5% but <40%; 55,820 beneficiaries), and 652 frequently performed ablation (≥40%; 15,637 beneficiaries). Beneficiaries undergoing surgical ablation (as-treated analysis) had a risk-adjusted median survival advantage of 4.40 months (95% CI, 2.40-6.36 months; 7.82 years [95% CI, 7.65-7.98 years] vs 7.46 years [95% CI, 7.38-7.57 years]; P < .001 for risk-adjusted survival comparison) compared with those without. Beneficiaries undergoing CABG by surgeons who frequently ablate (provider-preference analysis) had a risk-adjusted median survival advantage of 4.96 months (95% CI, 2.10-7.82 months; 7.03 years [95% CI, 6.90-7.20 years] vs 6.62 years [95% CI, 6.46-6.79 years], P < .001 for risk-adjusted survival comparison) compared with surgeons who infrequently ablate.

Conclusions: In Medicare beneficiaries with preexisting atrial fibrillation, concomitant surgical ablation during CABG is associated with improved survival, as is undergoing CABG by a surgeon who frequently ablates. Our findings support current guidelines recommending surgical ablation during CABG in patients with atrial fibrillation and highlight that ablation is currently underused in contemporary practice.