Association of a mild or an important decline in left ventricular ejection fraction with ventricular tachyarrhythmias, sudden cardiac death, and all-cause death in heart failure with preserved ejection fraction: a report from the CHART-2 Study

Aims A decline in left ventricular ejection fraction (LVEF) is often observed in patients with heart failure with preserved ejection fraction (HFpEF) and is associated with adverse outcomes. Although baseline LVEF is crucial for assessing the risk of sudden cardiac death in patients with HF, little is known about the relationship between the decline in LVEF and lethal arrhythmic events among patients with HFpEF. Methods and results We retrospectively analysed data from the CHART-2 Study. A total of 1453 patients with HF and LVEF ≥ 50% at registration (73 years, 39% female) were included and categorized into three groups based on their LVEF at the prespecified 1-year follow-up; 1316 with LVEF ≥ 50%, 120 with LVEF 36–50%, and 17 with LVEF ≤ 35%. The primary endpoint was a composite of ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. All-cause death was also evaluated. During a median follow-up of 7.9 years, 79 (5.4%) patients experienced a composite event. Patients with LVEF < 50% at 1 year had a significantly higher incidence of the composite event (11.7 vs. 4.8%, P < 0.001), and all-cause death (62.8% vs. 51.8%, P = 0.006), compared to those with LVEF ≥ 50%. Importantly, a decline in LVEF to <50% was independently associated with an increased risk of the composite event (adjusted hazard ratio 1.99, 95% CI 1.04–3.79, P = 0.04). Conclusion In patients with HFpEF, even a mild decline in LVEF was associated with a higher risk of ventricular tachyarrhythmia, sudden cardiac death, and all-cause death. Continuous clinical assessment and re-evaluation of LVEF is crucial for the management of patients with HFpEF.