Multivariable analysis of heart rate recovery after cycle ergometry in heart failure: exercise in heart failure

Purpose

The purpose of this study was to investigate the association between impairment in heart rate recovery (HR_rec) after cycle ergometry and prognostic markers in patients with heart failure (HF) compared with healthy controls.

Methods

Fifty patients with chronic HF (systolic HF, N = 30; diastolic HF, N = 20; mean age = 62 ± 12 years) and 50 healthy controls (N = 50; mean age = 66 ± 13 years) underwent 2-dimensional and M-mode echocardiography followed by cardiopulmonary exercise testing. Independent predictors of HR_rec at 1 and 2 minutes after exercise were analyzed by univariable and multivariable regression analyses, and receiver operating characteristics were performed to obtain area under the curve.

Results

In HF, left ventricular end-diastolic diameter (millimeters), left ventricular ejection fraction (%), N-terminal pro-brain natriuretic peptide (picograms/milliliter), peak oxygen uptake (VO₂peak [milliliters/kilogram/min]), and peak heart rate (HR_peak) showed a significant association with HR_rec (beats/min) in univariate regression analyses (P < .001), but only VO₂peak remained independently predictive of both HR_rec1 (P = .034) and HR_rec2 (P = .008) in the multivariable regression analyses. In controls, VO₂peak (P = .035) and HR_peak (P = .032) were significantly associated with HR_rec2 in univariate analyses only. Optimal cutoff values for discriminating HF versus non-HF based on HR_rec were 17.5 beats/min (sensitivity 92%; specificity 74%) for HR_rec1 and 31.5 beats/min (sensitivity 94%; specificity 86%) for HR_rec2. Optimal cutoff values for discriminating systolic HF versus diastolic HF were 12.5 beats/min (sensitivity 78%; specificity 80%) for HR_rec1 and 24.5 beats/min (sensitivity 82%; specificity 90%) for HR_rec2.

Conclusion

Impairment in after exercise HR_rec is significantly and independently associated with VO2peak in HF and thus might constitute a useful tool for assessing the degree of functional status during exercise rehabilitation.