Heart Failure With Mid-Range Or Improved Ejection Fraction Improves Cardiovascular Outcomes

Heart failure with improved ejection fraction (HFiEF) is a unique and developing clinical entity among the heart failure (HF) spectrum. Prior studies suggest the characteristics, therapy, and prognosis of HFiEF are distinctive from HF with reduced ejection fraction (HFrEF) or mid-range ejection fraction (HFmrEF). We hypothesized that patients diagnosed with acute HF who later progressed to HFiEF would have improved cardiovascular outcomes compared to HFrEF. Our retrospective study included 295 adult patients with no prior history of HF at The Ohio State University diagnosed with acute HF. We defined HFrEF as a persistent ejection fraction < 40%, HFmrEF as persistent ejection fraction 40-49%, and HFiEF as improvement from baseline ejection fraction by > 5%. Nearly 74% of patients were found to have HFiEF while 12% and 14% were classified as HFrEF and HFmrEF respectively. Using a log-rank test, the time to first cardiovascular rehospitalization was significantly longer in HFiEF compared to HFrEF or HFmrEF (p=0.0192, Figure 1). Multivariable analysis, controlled for age and gender, indicated HFiEF had a trend towards significance as an independent predictor for time to cardiovascular hospitalization (p=0.053). Notably amyloid HF, valvular HF, and ischemic HF were all significant independent predictors. Survival analysis demonstrated that HFmrEF had significantly longer survival on log-rank test compared to HFrEF (p=0.0367). Multivariable analysis shows significantly lower hazard of mortality for those with HFmrEF (HR 0.57, 95% CI [0.36-0.92], p=0.017). Our exciting data indicates the progression to HFiEF after the diagnosis of acute HF is associated with reduced cardiovascular rehospitalization, and HFmrEF is associated with increased survival. These data have implications in patient surveillance and risk stratification as well as defining the natural history of HFiEF and HFmrEF as unique entities.