Journal Article

Nonlinear heart rate variability in CABG patients and the preconditioning effect

Zhong-Kai Wu, Saila Vikman, Jari Laurikka, Erkki Pehkonen, Tiina Iivainen, Heikki V. Huikuri and Matti R. Tarkka

in European Journal of Cardio-Thoracic Surgery

Published on behalf of European Association for Cardio-Thoracic Surgery

Volume 28, issue 1, pages 109-113
Published in print July 2005 | ISSN: 1010-7940
Published online July 2005 | e-ISSN: 1873-734X | DOI:
Nonlinear heart rate variability in CABG patients and the preconditioning effect

More Like This

Show all results sharing these subjects:

  • Clinical Pharmacology and Therapeutics
  • Cardiovascular Medicine


Show Summary Details


Objective: Heart rate variability (HRV) is the most frequently used noninvasive diagnostic method in the assessment of cardiac autonomic control. The clinical relevance of HRV, especially nonlinear HRV in CPB patients has not been well studied. Short brief myocardial ischemia has been reported to influence HRV. We therefore hypothesis that the protective mechanism of ischemic preconditioning (IP) may involve in cardiac autonomic regulation. Methods: Eighty-six CABG patients were randomized into a control and an IP group. The IP patients received two periods of 2-min ischemia followed by 3-min reperfusion by aortic cross-clamped. Holter data were collected in 86 CABG patients before and after surgery. Arrhythmias, linear and nonlinear HRV measures were analyzed. Results: All time and frequency domain HRV variables as well as nonlinear indexes of HRV, the short-term (4–11 beats) scaling exponent α1, were suppressed significantly after surgery in both study groups. The lower pre- and postoperative exponent α1 predict the higher incidence of postoperative AF and worse postoperative outcome. The suppressed exponent α1 was attenuated in the IP group as compared to controls (P=0.008). No other differences were observed in the changes in linear HRV measures between the groups. IP significantly reduced the incidence of postoperative arrhythmias and improved postoperative outcome. Conclusions: The present findings show that cardiac autonomic regulation is impaired after CABG. Nonlinear HRV exponent α1 is a more sensitive measure to predict the postoperative outcome in CABG patients. IP alleviates the extreme autonomic reactions after surgery, suggesting that cardiac autonomic regulation is involved in the IP protective mechanism.

Keywords: Autonomic nervous system; Preconditioning; Cardiopulmonary bypass; Ischemia/reperfusion; Myocardial injury

Journal Article.  2939 words.  Illustrated.

Subjects: Clinical Pharmacology and Therapeutics ; Cardiovascular Medicine

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content. subscribe or purchase to access all content.