Abstract
AIMS: Guidelines for management of patients with heart failure with mid-range ejection fraction [HFmrEF; left ventricular EF (LVEF) 41-49%] do not exist. Disagreement exists whether HFmrEF should be considered a distinct group. The aim of this study is to examine characteristics of patients with HFmrEF with HF with reduced EF (HFrEF; LVEF ≤ 40%) or preserved EF (HFpEF; LVEF ≥ 50%). METHODS AND RESULTS: We examined data collected in the American College of Cardiology's National Cardiovascular Data Registry (NCDR) Practice Innovation and Clinical Excellence (PINNACLE) Registry® for first HF patient visits between 1 May 2008 and 30 June 2016. Analysis was performed using ANOVA F-tests (or Kruskal-Wallis tests for non-normally distributed variables) for continuous parameters and χ(2) tests for nominal covariates at the first diagnosed HF visit. Given the NCDR PINNACLE Registry® is a US-based registry, we opted to define HFmrEF as per the US guidelines, which define HFmrEF as LVEF 41-49% in contrast to European guidelines, which define HFmrEF as LVEF 40-49%. Among 1 103 386 patients with available data, 36.1% (N = 398 228) had HFrEF, 7.5% (N = 82 292) had HFmrEF, and 56.5% (N = 622 866) had HFpEF. Compared with patients with HFrEF or HFpEF, patients with HFmrEF had more prevalent coronary and peripheral artery disease and more history of myocardial infarction, percutaneous coronary intervention, or coronary artery bypass surgery (all P < 0.001). Patients with HFmrEF were also more likely to have atrial fibrillation/flutter, diabetes, and chronic kidney disease and to have a history of tobacco use (both P < 0.001). Among those with EF assessment prior to this analysis, only 4.8% (N = 1032) previously had HFrEF that improved to HFmrEF; 32.9% (N = 7072) had HFpEF previously and progressed to HFmrEF. Those patients who transitioned from HFpEF to HFmrEF had considerably more complex profiles and were less aggressively managed compared with those who remained with HFmrEF (all P < 0.001). CONCLUSIONS: In this large descriptive analysis, patients with HFmrEF had an atherothrombotic phenotype distinct from other forms of HF. Interventions aimed at treating coronary ischaemia and addressing prevalent risk factors may play a particularly important role in the management of patients with HFmrEF.