Functional outcome after cardiac rehabilitation and its association with survival in heart failure across the spectrum of ejection fraction.

Abstract

There is limited evidence regarding the effects of cardiac rehabilitation (CR) in patients with heart failure and preserved ejection fraction (HFpEF). We studied 1784 patients admitted to inpatient CR. The patients were grouped into HFpEF (EF≥0.50), HF with mildly reduced EF (HFmrEF; EF 41-49), and HF with reduced EF (HFrEF; EF≤0.40). A standardized 6-min walking test was performed at admission and discharge. Measures of functional outcome were: (1) absolute increase in 6-min walking distance (6MWD) from admission to discharge >50 m and (2) increase in 6MWD to ≥300 among the patients who walked <300 m at admission. After adjustment, the patients with HFpEF or HFmrEF were as likely as those with HFrEF to achieve an increase in 6MWD >50 m (odds ratio 0.95 [95%CI 0.71-1.24; p=0.648] and 1.04 [95%CI 0.77-1.41; p=0.769], respectively) or an increase in 6MWD to ≥300 m (odds ratio 0.79 [95%CI 0.51-1.23; p=0.299] and 0.65 [95%CI 0.38-1.12; p=0.118], respectively). The adjusted hazard ratio of 5-year mortality for patients who achieved an increase in 6MWD >50 m was 0.60 (95%CI 0.51-0.71; p<0.001) and that for patients who achieved an increase in 6MWD at discharge to ≥300 m 0.61 (95%CI 0.48-0.79; p<0.001). In each EF group, both outcomes remained independently associated with improved survival. Our data suggest that patients with HFpEF or HFmrEF are as likely as those with HFrEF to benefit from CR in terms of functional improvement. Functional improvement was independently associated with improved long-term survival, regardless of EF.