Surgical Ablation of Pre-Existing Atrial Fibrillation During Aortic Valve Replacement in Medicare Beneficiaries

Guidelines recommend surgical ablation (SA) during isolated aortic valve replacement (AVR) in patients with pre-existing atrial fibrillation (AF). Nevertheless, SA remains underutilized during AVR, and the impact of SA on long-term outcomes is poorly quantified. We examined the association of SA with survival and the incidence of stroke or transient ischaemic attack (TIA) in Medicare beneficiaries with AF undergoing AVR.

Medicare claims (2008-2019) were queried to identify patients with AF undergoing AVR; procedural characteristics were doubly adjudicated using hospital and surgeon billing codes. Kaplan-Meier survival estimates were generated for beneficiaries who did and did not receive concomitant SA. Ten-year restricted mean survival times (RMST) were compared; 95% confidence intervals are provided. Outcomes were re-analysed using surgeon frequency of SA as an instrumental variable. Overlap propensity score weighting was performed for risk-adjustment in all analyses.

Among 37 666 beneficiaries with AF undergoing AVR, only 8499 (22.6%) underwent SA. Surgeons were categorized by quartile of SA frequency during AVR: 1318 infrequently performed SA (<7.5% of cases; 9438 beneficiaries), whereas 786 frequently performed SA (≥34%; 9353 beneficiaries). Risk-adjusted RMSTs were 6.59 [6.49-6.69] vs 6.21 [6.11-6.31] years in beneficiaries with and without concomitant SA during AVR, a difference of 4.6 [1.8-7.4] months (P < 0.001). Risk-adjusted RMSTs were 6.14 [6.01-6.26] vs 5.94 [5.82-6.06] years for beneficiaries undergoing AVR by frequent and infrequent SA surgeons, a difference of 2.3 [0.2, 4.4] months (P = 0.03).

In Medicare beneficiaries with AF undergoing AVR, utilization of concomitant SA was associated with a clinically modest late survival advantage, as was undergoing surgery by a frequent SA surgeon.