Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007 Jul;12(3):185-96.
doi: 10.1111/j.1542-474X.2007.00160.x.

Circadian variation in QT dispersion determined from a 12-lead Holter recording: a methodological study of an age- and sex-stratified group of healthy subjects

Stig Hansen  1 , Verner Rasmussen, Klaus Larsen, Christian Torp-Pedersen, Gorm Boje Jensen
Affiliations

Circadian variation in QT dispersion determined from a 12-lead Holter recording: a methodological study of an age- and sex-stratified group of healthy subjects

Stig Hansen et al. Ann Noninvasive Electrocardiol. 2007 Jul.

Abstract

Background: QT dispersion is considered to reflect inhomogeneity of myocardial repolarization.

Method: The circadian variation of QT interval dispersion was examined in 95 healthy subjects using 24-hour Holter monitoring. Three different methods of lead selection were applied: all 12 leads (QTdisp 12), only precordial leads (QTdisp 6), and the pair of leads selected at 3 a.m. in which the longest and shortest QT intervals were found in each individual subject (QTdisp 2).

Results: A preliminary methodological study including measurements from every minute in 10 subjects revealed no significant circadian variation using mean values of QTdisp 12, QTdisp 6, or QTdisp 2 obtained every hour, every 2, or every 4 hours, except in QTdisp 6, which demonstrated a significant circadian variation (P < 0.01) in 1-hour measurements. Analysis of all 95 subjects using measurements obtained every 4 hours revealed a significant circadian variation in QTdisp 12 and QTdisp 6 (P < 0.0001), whereas no circadian variation was seen in QTdisp 2. A subdivision into 10-year age groups revealed that subjects at age >50 years had a significant circadian variation in QTdisp 12 and QTdisp 6, but not in QTdisp 2. Only in males a significant circadian variation was seen in QTdisp 12 (P < 0.0001), whereas QTdisp 6 demonstrated a circadian variation both in females (P < 0.001) and in males (P < 0.0001).

Conclusions: Selection of leads is of crucial importance for repetitive measurements of QT dispersion. Circadian variation was detected in subjects over 50 years of age, when all 12 or only the 6 precordial leads were taken into account.

PubMed Disclaimer

Figures

Figure 1
Figure 1
The circadian profile in each of the three modes of lead selection (QTdisp 12, QTdisp 6, and QTdisp 2) for each 10‐year age group is presented. P values of a MIXED models analysis of circadian variation are specified for each of the three modes of lead selection in each 10‐year age group.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Day CP, McComb JM, Campbell RW. QT dispersion: An indication of arrhythmia risk in patients with long QT interval. Br Heart J 1990;63:342–344. - PMC - PubMed
    1. Perkiömäki J, Koistinen M, Yli‐Mäyry S, et al Dispersion of QT Interval in patients with and without susceptibility to ventricular tachyarrhythmias after previous myocardial infarction. J Am Coll Cardiol 1995;26:174–179. - PubMed
    1. Muller JE, Stone PH, Turi ZG, et al Circadian variation in the frequency of onset of acute myocardial infarction. N Engl J Med 1985;313:1315–1322. - PubMed
    1. Rocco MB, Barry J, Campbell S, et al Circadian variation of transient myocardial ischemia in patients with coronary artery disease. Circulation 1987;75:395–400. - PubMed
    1. Willich SN, Levy D, Rocco MB, et al Circadian variation in the frequency of sudden cardiac death in the Framingham Heart Study population. Am J Cardiol 1987;60:801–806. - PubMed