Stroke and Myocardial Infarction Risk among Newly Diagnosed Heart Failure Patients with Reduced, Borderline, and Preserved Left Ventricle Ejection Fraction

      Introduction: There is limited data on contemporary cardiovascular (CV) event rates among heart failure (HF) patients with preserved or reduced ejection fraction (EF) in community practice. Our goal was to determine the association between EF and CV events in the HF population. Hypothesis: Among HF patients, those with reduced EF [<40%] will have higher CV event rates than those with borderline [40%-50%], or preserved [≥50%] EF (2013 ACC/AHA/HFSA guidelines). Methods: Using Integrated Claims/EHR data from Optum, we analyzed a cohort of adult patients newly diagnosed with a HF hospitalization or an emergency room visit between 07/2009 and 09/2016. Patients with a measurement of EF within a window of ±90 days around the index date were stratified by EF. Subsequent adverse CV events after index HF discharge were identified by a primary diagnosis documented during a hospitalization. Kaplan-Meier rates for stroke and acute myocardial infarction (MI) were evaluated over a 1-year period and differences were assessed using Cox proportional hazard models adjusting for baseline characteristics. Results: A total of 7,005 HF patients were included in the study of which 1,622, 1,095, and 4,288 formed the reduced, borderline and preserved EF cohorts, respectively. Patients in the preserved EF (pEF) cohort were older (74 vs. 72–73 years) and were mostly female (55% vs. 36–38%) compared with both reduced and borderline EF (rEF and bEF) cohorts. Compared with those with bEF and pEF, those with rEF had higher observed rates and adjusted risk for stroke at 1 year (5.4% vs 3.7% [bEF] and 3.9% [pEF], adjusted HR [95% CI]: 1.47 [0.94 - 2.32]; P = .093, and 1.40 [1.01 - 1.94]; P = .043, Fig. 1) despite a significantly lower prevalence of atrial fibrillation in the rEF patients. Similarly, patients with rEF had higher risk of MI at 1 year compared with bEF and pEF patients (7.5% vs 5.9% and 3.2%; adjusted HR [95% CI]: 1.28 [0.89 - 1.84] P = .179, and 2.53 [1.87 - 3.43]; P < .001). Conclusions: Among patients newly diagnosed with HF, those with rEF had significantly higher risks of ischemic stroke and MI compared with pEF patients and tended to have increased MI risk compared with bEF patients. Cardiovascular prevention in this high-risk population may attenuate some of this excess risk.
      Fig. 1
      Fig. 1Kaplan-Meier rates of Ischemic stroke* - excluding patients with stroke at baseline.