Back to Journals » Vascular Health and Risk Management » Volume 10

Heart rate variability measured early in patients with evolving acute coronary syndrome and 1-year outcomes of rehospitalization and mortality

Authors Harris P, Stein P, Fung G, Drew B

Received 13 November 2013

Accepted for publication 9 January 2014

Published 5 August 2014 Volume 2014:10 Pages 451—464


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 2

Patricia R E Harris,1 Phyllis K Stein,2 Gordon L Fung,3 Barbara J Drew4

1Electrocardiographic Monitoring Research Laboratory, School of Nursing, Department of Physiological Nursing, University of California, San Francisco, CA, USA; 2Heart Rate Variability Laboratory, School of Medicine, Division of Cardiology, Washington University, St Louis, MO, USA; 3Cardiology Services, Mount Zion, Department of Medicine, Division of Cardiology, University of California, San Francisco, CA, USA; 4School of Nursing, Department of Physiological Nursing, Division of Cardiology, University of California, San Francisco, CA, USA

Objective: This study sought to examine the prognostic value of heart rate variability (HRV) measurement initiated immediately after emergency department presentation for patients with acute coronary syndrome (ACS).
Background: Altered HRV has been associated with adverse outcomes in heart disease, but the value of HRV measured during the earliest phases of ACS related to risk of 1-year rehospitalization and death has not been established.
Methods: Twenty-four-hour Holter recordings of 279 patients with ACS were initiated within 45 minutes of emergency department arrival; recordings with ≥18 hours of sinus rhythm were selected for HRV analysis (number [N] =193). Time domain, frequency domain, and nonlinear HRV were examined. Survival analysis was performed.
Results: During the 1-year follow-up, 94 patients were event-free, 82 were readmitted, and 17 died. HRV was altered in relation to outcomes. Predictors of rehospitalization included increased normalized high frequency power, decreased normalized low frequency power, and decreased low/high frequency ratio. Normalized high frequency >42 ms2 predicted rehospitalization while controlling for clinical variables (hazard ratio [HR] =2.3; 95% confidence interval [CI] =1.4–3.8, P=0.001). Variables significantly associated with death included natural logs of total power and ultra low frequency power. A model with ultra low frequency power <8 ms2 (HR =3.8; 95% CI =1.5–10.1; P=0.007) and troponin >0.3 ng/mL (HR =4.0; 95% CI =1.3–12.1; P=0.016) revealed that each contributed independently in predicting mortality. Nonlinear HRV variables were significant predictors of both outcomes.
Conclusion: HRV measured close to the ACS onset may assist in risk stratification. HRV cut-points may provide additional, incremental prognostic information to established assessment guidelines, and may be worthy of additional study.

Keywords: autonomic cardiac function, coronary artery disease, outcomes research, risk assessment, hospital readmittance, mortality

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]