Heart failure with improved ejection fraction: clinical characteristics, correlates of recovery, and survival

Background - Heart failure with recovered or improved ejection fraction (HFiEF) has been proposed as a new category of HF. Whether HFiEF is clinically distinct from HF with persistently reduced ejection fraction remains to be validated. Methods and Results - Of the 5010 subjects enrolled in the Valsartan Heart Failure Trial (Val-HeFT), 3519 had a baseline left ventricular EF of <35% and a follow-up echocardiographic assessment of EF at 12 months. Of these, 321 (9.1%) patients who had a 12-month EF of >40% constituted the subgroup with HFiEF. EF improved from 28.7±5.6% to 46.5±5.6% in the subgroup with HFiEF and remained reduced (25.2±6.2% and 27.5±7.1%) in the subgroup with HF with reduced ejection fraction. The group with HFiEF had a less severe hemodynamic, biomarker, and neurohormonal profile, and it was treated with a more intense HF medication regimen. Subjects who had higher blood pressure and those treated with a β-blocker or randomized to valsartan had greater odds of being in the HFiEF group, whereas those with an ischemic pathogenesis, a more dilated left ventricle, and a detectable hs-troponin had lower odds of an improvement in EF. Recovery of the EF to >40% was associated with a better survival compared with persistently reduced EF. Conclusions - Our data support HFiEF as a stratum of HF with reduced ejection fraction with a more favorable outcome, which occurs in a minority of patients with HF with reduced ejection fraction who have a lower prevalence of ischemic heart disease, a less severe hemodynamic, biomarker, and neurohormonal profile, and who are treated with a more intense HF medication regimen.