Prognostic value of heart rate recovery in patients with heart failure

Arena, Ross PhD, PT
Guazzi, Marco MD, PhD
Myers, Jonathan PhD
Peberdy, Mary Ann MD

^aDepartment of Physical Therapy, Virginia Commonwealth University, Health Sciences Campus, Richmond, VA
^bCardiopulmonary Laboratory, Cardiology Division, University of Milano, San Paolo Hospital, Milano, Italy
^cCardiology Division, VA Palo Alto Health Care System, Stanford University, Palo Alto, CA
^dDepartment of Internal Medicine, Virginia Commonwealth University, Health Sciences Campus, Richmond, VA

Reprint requests: Ross Arena, PhD, PT, Department of Physical Therapy, Box 980224, Virginia Commonwealth University, Health Sciences Campus, Richmond, VA 23298-0224. E-mail: [email protected]

Received for publication April 29, 2005; accepted September 14, 2005

American Heart Journal 151(4):p 851e7-851e13, April 2006.

Background

The rate in which heart rate recovers from exercise has recently been shown to be a strong predictor of mortality in patients suspected of having coronary disease, but its prognostic value in patients with heart failure (HF) has not been explored. We sought to assess the prognostic utility of heart rate recovery (HRR) in patients with HF.

Methods

Eighty-seven subjects diagnosed with compensated HF underwent cardiopulmonary exercise testing (CPX). Mean age and ejection fraction were 50.0 (±13.9) years and 28.1% (±13.6%), respectively. Heart rate at 1-minute post-CPX was subtracted from maximal heart rate during the exercise test to produce a measure of HRR₁ in beats per minute. Subjects were followed for a combined death/hospitalization end point for 1-year after CPX.

Results

The mean peak respiratory exchange ratio, peak oxygen consumption (VO₂), minute ventilation/carbon dioxide production (VE/VCO₂) slope, and HRR₁ were 1.06 (±0.11), 14.8 (±4.7) mL · kg⁻¹ · min⁻¹, 36.6 (±8.6), and 11.0 (±10.4) beat/min, respectively. Although all three variables were significant univariate predictors of the composite end point (P < .001), multivariate Cox regression analysis only retained the VE/VCO₂ slope (χ² = 33.5, P < .001) and HRR₁ (residual χ² = 15.0, P < .001) in the equation. The hazard ratio for subjects having both an abnormal VE/VCO₂ slope (>34.4) and HRR₁ (<6.5 beat/min) value was 9.2 (95% CI 4.5–18.5, P < .0001).

Conclusions

These results indicate that HRR provides additional prognostic information in patients with HF undergoing CPX. Moreover, given the independent prognostic value of HRR, this variable alone may provide valuable clinical information when ventilatory expired gas analysis is not available.