Abstract 4141805: High Frequency of Ejection Fraction Decline in Patients with Heart Failure with Improved Ejection Fraction

Background: Heart failure with improved ejection fraction (HFimpEF) is defined by prior HF with reduced EF (HFrEF) and evidence of systolic improvement and is associated with improved outcomes. Despite this, HFimpEF patients remain at risk of future adverse events, including EF decline. However, little is known about factors associated with EF trajectory in this population. Question: Are baseline clinical characteristics associated with future EF decline in HFimpEF? Goals: To describe the EF trajectory in HFimpEF and to identify if clinical characteristics are predictive of eventual EF decline. Methods: This was a retrospective observational study of 115 patients in our HFimpEF registry. Inclusion criteria were a history of HFimpEF (prior HFrEF [EF ≤40%] with subsequent EF improvement ≥10% and resulting EF >40%) and at least one follow-up echocardiogram after improvement. The primary outcome was EF decline (EF drop ≥10% from peak improvement EF). Cox proportional hazard models were built using baseline factors at time of HFrEF diagnosis to identify predictors of EF decline. Results: The median time from initial HFrEF diagnosis to development of HFimpEF was 0.61 years (IQR 0.26-1.17). Most patients (77%) continued to have EF improvement after HFimpEF diagnosis, and the peak EF was 60% (IQR 54-65%). Over a mean follow-up of 4.7±3.2 years, 35 (30%) HFimpEF patients developed EF decline. Baseline characteristics were similar between those with sustained EF and EF decline ( Table 1 ), as was peak EF (60.0% vs 60.3%, p=0.571). Indexed end-systolic dimension (1.78 vs 1.93 cm/m 2 , p=0.014) was smaller at time of HFimpEF diagnosis in those with sustained EF. In multivariate analysis, current/former tobacco use was associated with EF decline (HR 2.60, 95% CI 1.02-6.63, p=0.045; Table 2 ). Conclusions: Many HFimpEF patients develop EF decline, highlighting the need for continual clinical follow up in this high-risk patient population.