Heart rate recovery after the 6 min walk test rather than distance ambulated is a powerful prognostic indicator in heart failure with reduced and preserved ejection fraction: A comparison with cardiopulmonary exercise testing

Department of Physical Therapy, Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA.
European Journal of Heart Failure (Impact Factor: 6.53). 02/2013; 15(5). DOI: 10.1093/eurjhf/hfs216
Source: PubMed


Heart rate recovery (HRR) appears to be a robust prognostic marker in heart failure (HF). When using the 6 min walk test (6MWT) in HF, distance ambulated is generally the reference prognostic variable. We hypothesized that HRR after the 6MWT would be a better prognostic measure than distance ambulated.

Methods and results:
A 6MWT and cardiopulmonary exercise testing (CPX) were randomly performed in 258 HF patients [216 HF with reduced EF (HFrEF) and 42 HF preserved EF (HFpEF)], after which HRR was measured. HRR was defined as the difference between heart rate at peak exercise and 1 min following test termination. Patients were assessed for major cardiac events during a mean follow-up period of 22.8 ± 22.1 months. There were 50 major cardiac events during the tracking period. Univariate Cox regression analysis results identified HRR after both the 6MWT and CPX as a significant (P < 0.001) predictor of adverse events. Multivariate Cox regression analysis revealed that dichotomized HRR after the 6MWT and CPX was the strongest predictor of survival (χ(2) 61.1 and 53.8, respectively; P < 0.001), with LVEF (residual χ(2) 6.1, P < 0.05) adding significant prognostic value to the 6MWT model and ventilatory efficiency (the VE/VCO2 slope) (residual χ(2) 6.6, P < 0 .05) adding significant prognostic value to the CPX model.

HRR after the 6MWT is a powerful prognosticator that performs similarly to HRR after maximal exercise. If confirmed in subsequent studies, 6MWT HRR should replace 6MWT distance as the reference criterion 6MWT measure to consider when grading cardiovascular risk in HF patients.

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Available from: Ross Arena, Nov 09, 2015
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    • "[16] Combinations of the above stated definitions ≥3 regular oscillatory fluctuations in VE, with minimal average amplitude of ≥5 l/min persisting for ≥60% of the entire exercise time. [65] [41] [71] N60% duration; amplitude of N30% of the mean VE. [34] [53] Oscillations ≥60% of entire exercise data at an amplitude N15%; amplitude of VE ≥5 l/min; a regular oscillation as defined by a SD of 3 consecutive cycle lengths within 20% of the average. [31] [43] [42] Cyclic fluctuation of VE at rest and during exercise with amplitude swings N30% of the mean VE, N15% for ≥60% of incremental exercise duration. "
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