Impact of the degree of LV dysfunction
AF is known to be associated with increased mortality only in patients with HF with a preserved EF (HFpEF), defined as the presence of signs and symptoms of HF with an EF of >50%.9In our report,10 a total of 106 consecutive HF patients, including 51 (48.1%) with a reduced left ventricular ejection fraction (LVEF) (HFrEF) and 55 (51.9%) with a preserved LVEF (HFpEF), underwent AF ablation. All patients underwent a successful PVAI, and substrate modification was added in 38 (35.8%). In the patients with HFrEF, normalization of the LVEF (LVEF ≧ 50%) was observed in 37 (72.5%) patients during the follow-up period. Multivariate logistic analyses revealed that a smaller left ventricular end-diastolic diameter (LVDd) was the sole parameter predicting an LVEF normalization post-procedure (odds ratio [OR] = 0.863; 95% confidence interval [CI] = 0.779–0.955, p = 0.005). For the association between the LVDd and LVEF normalization post-procedure, the area under curve (AUC) of 0.774 (95% CI = 0.618–0.930) was observed. The optimal cut-off point for the LVDd for predicting an LVEF normalization post-procedure was 53.5 mm (sensitivity 64.9%, specificity 78.6%). Interestingly, in the CASTLE-AF trial, there was a significant interaction between the left ventricular ejection fraction (LVEF) and primary endpoint (death from any cause or admission for worsening heart failure), which implies that patients with an LVEF of 25% or more are more likely to have a benefit from ablation of AF than those with an LVEF of less than 25%.5