gms | German Medical Science

33rd International Congress on Electrocardiology

International Society of Electrocardiology

The Circadian Index as new simple method for assessment of the circadian heart rate

Meeting Abstract

  • corresponding author presenting/speaker L. Makarov - Moscow Institute Pediatry and Children Surgery, Moscow, Russland
  • S. Chuprova - Moscow Institute Pediatry and Children Surgery, Moscow, Russland
  • V. Komoliatova - Moscow Institute Pediatry and Children Surgery, Moscow, Russland
  • E. Petukhova - National Medical Surgery Center after N.I.Pirogov, Moscow, Russland

33rd International Congress on Electrocardiology. Cologne, 28.06.-01.07.2006. Düsseldorf, Köln: German Medical Science; 2007. Doc06ice110

The electronic version of this article is the complete one and can be found online at:

Published: February 8, 2007

© 2007 Makarov et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Aim of this study was to assess of circadian profile of heart rate in pts with cardiac diseases.

Methods: 24 hr Holter monitoring (HM), Oxford, UK, was performed in 201 pts 3-45 years. Indications for HM recording were arrhythmias detected on 12 leads ECG and diseases with high risk of life-threatening arrhythmias: extrasystoles (EX) 87 pts; atrial flutter (AF) 7 pts; sick sinus syndrome (SSS) 24 pts; complete AV block (AVB) 35 pts; long QT syndrome (LQTS) 11pts, catecholaminergic ventricular tachycardia (CVT) 10 pts; primary pulmonary hypertension (PPH) 15 pts, ishemic heart deseases (IHD) 12 pts. The control group (C) consisted of 115 healthy persons 3- 45 years. Circadian Index (CI) was calculated as ratio of mean HR (bpm) during awake period to mean HR (bpm) during night-sleep time.

Results: CI in patients with arrhythmias is summarized in Table 1 [Tab. 1]. * P <0,05 with control group Also the CI was calculated by the literature data (from the data of 20 published works) in various groups on healthy subjects and pts aged 2-79 years. In healthy subjects CI was stable irrespective of sex and age - 1,33 ± 0, 05. The reduction of CI < 1,2 was in cardiovascular pts with deterioration of the prognosis and autonomic denervation (diabetes mellitus with autonomic neuropathy). In neurological pts free of autonomic heuropathy CI was normal. CI > 1,46 was seen in patients with a basic high sensitivity to catecholamines.

Conclusion: CI reflected a ‘strong’ component in architecture of circadian heart rate. Decreased of CI shows the reduced of autonomic influence on heart rate. Increased of CI reflected high heart rates sensibility to sympathetic influence.