Clinical outcomes and structural remodelling after ablation of atrial fibrillation in heart failure with mildly reduced or mid-range ejection fraction

Aims The efficacy of catheter ablation (CA) on clinical outcomes and cardiac structural remodelling in atrial fibrillation (AF) patients with HF with mildly reduced or mid-range ejection fraction (HFmrEF) remains unclear. We aimed to compare the efficacy of CA with medical therapy (MT) in AF patients with HFmrEF. Methods and results We retrospectively screened a total of 36 879 patients with AF between 2005 and 2020. Patients who were initially diagnosed with echocardiography-proved HFmrEF and had follow-up echocardiography were enrolled. After applying propensity score matching in a 1:1 ratio, 72 patients treated by CA (Group 1) and 72 patients receiving MT (Group 2) were taken into further analysis. The co-morbidities were similar between the two groups, except for hyperlipidaemia. After a mean follow-up duration of 58.9 +/- 42.6 months, Group 1 had a lower HF hospitalization and all-cause mortality compared with Group 2 (hazard ratio (HR), 0.089 [95% confidence interval (CI), 0.011-0.747]; P = 0.026 and HR, 0.121 [95% CI, 0.016-0.894]; P = 0.038, respectively). As for cardiac structural remodelling, the Group 1 had a better improvement in left ventricular ejection fraction (LVEF) and a more decreased left atrium (LA) diameter than Group 2 (+25.0% +/- 18.0% vs. +6.2% +/- 21.6%, P = <0.0001 and -1.6 +/- 4.7 mm vs. +1.5 +/- 8.2 mm, P = 0.008, respectively). Conclusions In patients with HFmrEF and AF, CA of AF could reduce both HF hospitalization and all-cause mortality as compared with those with MT. A significant improvement in LVEF and decrease in LA diameter were also observed in the CA group. Early rhythm control with CA should be taken into consideration in patients with HFmrEF and AF.