Abstract
Background: Left ventricular (LV) longitudinal myocardial function is associated with the outcomes of heart failure (HF) patients. HF with improved ejection fraction (EF), known as HFimpEF, which is defined as current LVEF >40% but any previously documented LVEF ≤40%, has favorable outcomes compared with HF with preserved EF (HFpEF). However, LV longitudinal myocardial function in patients with previously reduced LVEF (<50%) but improved LVEF to within the normal range (≥50%) (HFnorEF) and its association with cardiovascular events remain unclear. Methods and Results: We studied 70 patients with HFpEF and 65 with HFnorEF. LV longitudinal myocardial function was assessed as global longitudinal strain (GLS). The primary endpoint was defined as cardiovascular death or HF hospitalization during follow-up of 5.6±3.1 years. The GLS of HFpEF patients was significantly lower than that of HFnorEF patients (13.6±3.5% vs. 14.8±2.2%, P=0.02) even when the LVEF was similar. Multivariate Cox proportional hazards analysis showed that GLS was independently associated with cardiovascular events. Furthermore, of the entire study population, patients with GLS >15.0% had fewer cardiovascular events than those without (log-rank P=0.014) among all the patients. Conclusions: LV longitudinal myocardial dysfunction was more frequently observed in patients with HFpEF than in those with HFnorEF, even when LVEF was similar, and was independently associated with cardiovascular events for HF patients with current LVEF ≥50%.