Long-Term Outcomes of Continuous ECG Monitoring Following Catheter Ablation in Patients with Persistent Atrial Fibrillation and Left Ventricular Systolic Dysfunction

Background: Catheter ablation of atrial fibrillation (AFCA) has become a standard treatment for patients (pts) with heart failure (HF) and left ventricular systolic dysfunction (LVSD). However, the degree to which AF contributes to LVSD (AF-mediated cardiomyopathy) varies widely within the diverse HF population. Accurately identifying patients who are most likely to benefit from AFCA and refining treatment strategies remain important clinical challenges.

Purpose: To evaluate the effect of continuous ECG monitoring on long-term outcomes following AFCA in patients with persistent AF and LVSD, and to identify independent predictors of echocardiographic response to AFCA.

Methods: Consecutive pts with LVSD who underwent catheter ablation for persistent AF along with implantable loop recorder insertion for continuous ECG monitoring between January 2016 and February 2022 were included in the analysis if they met the following criteria: i) LVEF <50% in sinus rhythm at predischarge echocardiographic examination; and ii) a minimum echocardiographic follow-up (FU) period of 12 months. Pts were monitored for AF recurrence (defined as any >30-second episode occurring after a 90-day blanking period), AF burden, and change in LVEF at 12 months. Response to AFCA was defined as an increase in LVEF by ≥10% or full recovery of LVEF during FU.

Results: A total of 160 pts (65±11 years; 21% female) were included and followed for a median of 36.2 (IQR 18.6–49.6) months. The mean baseline LVEF was 36±8%, with 98% of pts having persistent AF, and 17% requiring repeat AFCA. At the 12-month FU, LVEF improved to 46±10% (p<0.001), with 102 pts (64%) responding to AFCA. LVEF improvement ≥10% was observed in 90 pts (56%), and LVEF normalization in 76 pts (48%). The median absolute change in LVEF from baseline was +9.9% (IQR 1.8 to 17.0%) overall, +15.9% (IQR 10.0 to 20.0%) in responders vs. -1.1% (IQR -4.8 to 3.8%) in non-responders (p=0.027). The overall AF recurrence rate at 12-month post-AFCA was 29.4%, with a median AF burden of 6.6% (IQR 3.7 to 9.5%). Compared to non-responders, responders had a significantly lower AF recurrence rate (23.5 vs. 39.7%; p=0.025) and AF burden (3.8 vs. 12.0%; p=0.030). Responders were also significantly younger (63 vs. 68 years; p=0.005), had less frequent structural heart disease (37% vs. 64%; p=0.001), and a shorter HF history (1.5 vs. 2.9 years; p=0.050). Absence of prior HF hospitalization (OR 0.652; 95% CI 0.411 - 0.923; p=0.014) and median AF burden (OR 0.971; 95% CI 0.960–0.994; p=0.021) were predictive of echocardiographic response to AFCA.

Conclusions: Persistent AF is a common cause or contributor to LVSD. Achieving rhythm control through AFCA leads to significant improvements in LV systolic function, especially in younger pts without underlying structural heart disease. In our study cohort, long-term continuous ECG monitoring was essential for assessing AF burden, which emerged as an independent predictor of echocardiographic response to AFCA.