Heart failure with normal ejection fraction is uncommon in acute myocardial infarction settings but associated with poor outcomes: a study of 91,360 patients admitted with index myocardial infarction between 1998 and 2010

Abstract

Aim: Data are scant on the incidence and prognosis of heart failure (HF) with normal ejection fraction (HFNEF, EF >49%) in an acute myocardial infarction (AMI) setting. The aim of this study was to examine incidence and predictors of HFNEF during an index acute myocardial infarction (AMI) and its subsequent associations with patient outcomes.

Methods and results: This study analysed 91 360 patients with LVEF data from the SWEDEHEART registry on consecutive AMI patients between 1998 and 2010. Echocardiography or LV angiography was used to assess LVEF. In-hospital HF diagnoses required presence of crackles, and use of i.v. diuretics or inotropic drugs during admission. Among HF patients, the proportion of HFNEF patients increased (from 18% to 31%) during the period. Incidence of HFNEF in the AMI population remained fairly unchanged (from 7.7% to 8.1%). In contrast, the proportion of HF patients with reduced EF (HFREF, EF ≤49%) declined (from 47% to 26%), as did the proportion of REF patients without HF (from 20% to 16%). AMI patients with NEF without HF increased (from 25% to 50%). HFREF and HFNEF patients showed considerably higher long-term mortality compared with patients with no HF, irrespective of EF [the HFREF and HFNEF hazard ratio, compared with NEF, was 4.5 (4.4-4-6) and 3.3 (3.1-3.4), respectively, and 1.6 (1.5-1.65) for REF]. The adjusted HFNEF hazard ratio, compared with NEF, was 1.9 (1.8-2.0). Age, female gender, diabetes mellitus, hypertension, AF, and chronic kidney disease were strong predictors of HFNEF (P < 0.001).

Conclusion: The proportion of AMI patients with HFNEF is constant over time. HFNEF patients have a considerably worse long-term prognosis compared with patients without clinical HF, irrespective of EF.

Keywords: Heart failure; Myocardial infarction; Normal EF; Predictors; Prognosis.