The prognostic value of the heart rate response during exercise and recovery in patients with heart failure: Influence of beta-blockade

Background: The heart rate increase during exercise (Delta HR) and heart rate recovery (HRR) have demonstrated prognostic value in several investigations, but its application in the heart failure (HF) population is limited, particularly in a beta-blocked (BB) cohort. Methods: Five-hundred and twenty subjects with HF underwent cardiopulmonary exercise testing to determine peak oxygen consumption (VO2), the minute ventilation/carbon dioxide production (VE/VCO2) slope, Delta HR and HRR at 1 min (HRR1). Results: There were 79 cardiac-related deaths during the tracking period. A HRR1 threshold of </>= 16 beats/min was a significant prognostic marker in the overall group (hazard ratio: 4.6, 95% CI: 2.8-7.5, p<0.001) as well as no-BB (hazard ratio: 9.1, 95% CI: 4.1-20.2, p<0.001) and BB (hazard ratio: 2.9, 95% CI: 1.6-5.4, p<0.001) subgroups. The Delta HR was a significant univariate predictor in the overall group and no-BB subgroup only. Multivariate Cox regression analysis revealed HRR1 was the strongest prognostic marker (chi-square: 39.9, p<0.001). The VE/VCO2 slope (residual chi-square: 21.8, p<0.001) and LVEF (residual chi-square: 9.6, p=0.002) were also retained in the regression. Conclusions: These results indicate that HRR maintains prognostic value in HF irrespective of BB use. The routine inclusion of HRR in the prognostic assessment of patients with HF may be warranted. (C) 2008 Elsevier Ireland Ltd. All rights reserved.