Heart failure with recovered ejection fraction: a distinct clinical entity.

BACKGROUND: A subset of patients with heart failure (HF) and preserved left ventricular ejection fraction (EF) previously had EF <40%. We postulated that such "recovered" EF patients would be prevalent in a referral HF population and clinically distinct from those with persistently preserved or reduced EF. METHODS AND
RESULTS: We identified all subjects with a clinical diagnosis of HF seen in the advanced heart disease practice at our center from March to October 2008. Patients were classified into 1 of 3 groups based on retrospective review of the medical record: EF persistently ≥40% (HF-PEF), EF recovered to ≥40% (HF-REF) and low EF, <40% (HF-LEF). Clinical and echocardiographic characteristics were compared across groups using standard chi-square and analysis of variance tests. A total of 358 heart failure patients were identified, including 56 with HF-PEF, 121 with HF-REF, and 181 with HF-LEF. Compared with HF-PEF, HF-REF patients were younger with less atrial fibrillation, hypertension, and diabetes. Also, they tended to have lower systolic blood pressure, better renal function, and larger left ventricular diameter at end diastole. HF-REF patients were more similar to HF-LEF, but were younger and had lower rates of coronary artery disease. Of the 3 groups, HF-REF patients had the mildest reported HF symptoms and fewest previous HF hospitalizations.
CONCLUSIONS: Patients with HF-REF comprise a substantial proportion of those with HF and EF ≥40% followed in an ambulatory referral practice. These patients appear to be clinically distinct from the residual HF population and should be specifically targeted for further research.