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 (VO ₂peak [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 VO ₂peak remained independently predictive of both HR _rec1 (P =.034) and HR _rec2 (P =.008) in the multivariable regression analyses. In controls, VO ₂peak (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.