Differential impact of atrial fibrillation ablation versus cardioversion on longitudinal biological age trajectories

Background Atrial fibrillation (AF) is associated with accelerated biological ageing. Artificial Intelligence-enabled ECG (AI-ECG) estimates biological age and the resulting absolute pre-ablation biological age gap (biological minus chronological age) predicts procedural success, as does the acute change in the age gap post AF-ablation. However, there is scant longitudinal data, including whether long-term trajectories of biological ageing are altered by procedures to restore sinus rhythm. Purpose To characterise and compare longitudinal biological age gaps in patients undergoing AF ablation versus direct current cardioversion (DCCV). We hypothesised that patients receiving AF ablation and DCCV would demonstrate divergent long-term ageing trajectories. Methods We analysed 1,879 patients undergoing DCCV or first AF ablation (paroxysmal or persistent) from 2010–2014, with at least one ECG available ≥30 days pre- and ≥90 days post-procedure at a single tertiary teaching hospital. Linear mixed models with cubic splines estimated the biological age gap trajectory from 1 year pre- to 3 years post-procedure. We adjusted for concurrent ECG rhythm to isolate substrate-driven progression from transient rhythm effects. Results The cohort (mean age 65±12 years, 30% female) included 86% DCCV, 7.0% paroxysmal, and 6.8% persistent AF ablation cases with a median 10 ECGs each available for analysis (IQR 5-22). Trajectories significantly differed by group (likelihood ratio test for group-by-time interaction P<0.001). The DCCV group showed transient pre-procedural ageing with early reversion post-procedure. Conversely, ablation groups had higher baseline age gaps (>4 years) with divergent trends. Persistent AF ablation demonstrated a distinct "U-shaped" trajectory: initial post-procedural age rejuvenation followed by a rebound ageing at ~18 months. Conclusion Cardiac rhythm interventions are associated with distinct, non-uniform effects on biological ageing trajectories. Unlike the transient stress pattern in cardioverted patients, persistent AF ablation shows a biphasic response with early improvement followed by late deterioration. These findings suggest AI-ECG biological age captures dynamic cardiovascular remodelling, offering a novel continuous metric for monitoring substrate-level procedural impact beyond AF recurrence.