Association of Holter-Derived Heart Rate Variability Parameters With the Development of Congestive Heart Failure in the Cardiovascular Health Study

Abstract

Objectives: This study sought to determine whether Holter-based parameters of heart rate variability (HRV) are independently associated with incident heart failure among older adults in the CHS (Cardiovascular Health Study) as evidenced by an improvement in the predictive power of the Health Aging and Body Composition Heart Failure (Health ABC) score.

Background: Abnormal HRV, a marker of autonomic dysfunction, has been associated with multiple adverse cardiovascular outcomes but not the development of congestive heart failure (CHF).

Methods: Asymptomatic CHS participants with interpretable 24-h baseline Holter recordings were included (n = 1,401). HRV measures and premature ventricular contraction (PVC) counts were compared between participants with (n = 260) and without (n = 1,141) incident CHF on follow-up. Significantly different parameters between groups were added to the components of the Health ABC score, a validated CHF prediction tool, using stepwise Cox regression.

Results: The final model included components of the Health ABC score, In PVC counts (adjusted hazard ratio [aHR]: 1.12; 95% confidence interval [CI]: 1.07 to 1.19; p < 0.001) and the following HRV measures: abnormal heart rate turbulence onset (aHR: 1.52; 95% CI: 1.11 to 2.08; p = 0.009), short-term fractal scaling exponent (aHR: 0.27; 95% CI: 0.14 to 0.53; p < 0.001), in very low frequency power (aHR: 1.28; 95% CI: 1.02 to 1.60; p = 0.037), and coefficient of variance of N-N intervals (aHR: 0.94; 95% CI: 0.90 to 0.99; p = 0.009). The C-statistic for the final model was significantly improved over the Health ABC model alone (0.77 vs. 0.73; p = 0.0002).

Conclusions: Abnormal HRV parameters were significantly and independently associated with incident CHF in asymptomatic, older adults. When combined with increased PVCs, HRV improved the predictive power of the Health ABC score.

Keywords: heart failure; heart rate variability; risk prediction.

Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Figures

FIGURE 1. The Health ABC Heart Failure Risk Score

Individual components of the score with their corresponding point values as outline by the original Health ABC Heart Failure study. Reprinted with permission from Butler et al. (2). BP = blood pressure; bpm = beats/min; HF = heart failure; LV = left ventricular.

FIGURE 2. Forest Plot of Adjusted Model Hazard Ratios and 95% Confidence Intervals

Components of the final model, as defined in Tables 1 and 2, are shown in graphical form with corresponding hazard ratios. Very low-frequency power indicates variance in heart rate variability at underlying frequencies of every 25 s to every 5 min calculated for every 15-min segment and averaged. CAD = coronary artery disease; CI = confidence interval; CV (%) = average coefficient of variance of N–N intervals for 5-min segments for 24 h; DFA1 = short-term fractal scaling exponent calculated over 3 to 11 beats and averaged over 1,000 beats for 24 h; HRT = heart rate turbulence; ln (PVC + 1) = natural log transformation of the number of premature ventricular contractions + 1; ln (VLF24) = natural log transformation of very low frequency power which indicates variance in heart rate variability at underlying frequencies of every 25 s to every 5 min, calculated for every 15-min segment and averaged. LVH = left ventricular hypertrophy; PVC = premature ventricular contraction.