Recent data demonstrates promising effects on left ventricular (LV) dysfunction and LV ejection fraction (EF) improvement following ablation for atrial fibrillation (AF) in patients with heart failure (HF). We sought to study the relationship between LVEF, NYHA class on presentation and the endpoints of mortality and HF admissions in the CASTLE-AF study population. Furthermore, predictors for LVEF improvement were examined.
The CASTLE-AF patients with coexisting HF and AF (n=363) were randomized in a multicenter prospective controlled fashion to ablation (n=179) vs pharmacological therapy (n=184). LV function and NYHA class were assessed at baseline (after randomization) and at each follow-up visit.
In the ablation arm, a significantly higher number of patients experienced an improvement in their LVEF to >35% at the end of the study (OR=2.17; p<0.001). Compared to the pharmacological therapy arm, both ablation patient groups with severe (<20%) or moderate/severe (≥20% and <35%)) baseline LVEF had a significantly lower number of composite endpoints (hazard ratio (HR) =0.60; p=0.006), all-cause mortality (HR=0.54; p=0.019) and cardiovascular (CV) hospitalizations (HR=0.66; p=0.017). In the ablation group, NYHA I/II patients at the time of treatment had the strongest improvement in clinical outcomes (primary endpoint: HR=0.43; p<0.001; mortality: HR=0.30; p=0.001).
Compared to pharmacological treatment, AF ablation was associated with a significant improvement in LVEF, independent from the severity of LV dysfunction. AF ablation should be performed at early stages of the patient's HF symptoms.