RT-45
|
Transmural dispersion assessed
from Holter recording: a new approach to detect repolarization abnormalities in patients
with inducible ventricular tachycardia after myocardial infarction
|
|
|
A. Lubinski, M. Kempa, E.
Lewicka-Nowak, A.M. Baczynska, G. Swiatecka.
II Department of Cardiology, Medical University of Gdansk, Poland
|
|
Abstract
|
|
Objectives. Recent experimental
studies demonstrated that the time interval from the peak to the end of the T-wave is
related to the difference in action potential course between epicardial, midmyocardial
M-cells and endocardial "layers" and that it is thought to reflect the
transmural dispersion in repolarization. Since propensity to sustained ventricular
tachycardia is known to be associated with increased dispersion of repolarization we aimed
to evaluate the time interval from the peak to the end of the T-wave in patients with
inducible sustained ventricular tachycardia and remote myocardial infarction (VT group).
Patients and methods. The study group consisted of 10 patients in the
VT group and 13 healthy persons (control group). 24-hour ECG recordings were analized with
Oxford Medilog Excel 2 system. The peak and the end of the T-wave intervals (TpTo) were
automatically identified during every hour and the mean TpTo from 24-hours was calculated.
The univariate Anova statistical analysis was used to compare transmural dispersion
between the groups.
Results. TpTo was 86 ± 24 msec (64-139 msec) in the VT group and 64
± 9 msec (51-81 msec) in the control group (p < 0.01). TpTo interval expressed as the
percentage value of the QT interval (TpTo/QT x 100%) was 23 ± 5% and 19 ± 2% in the VT
and the control group, respectively (p = 0.02).
Conclusion. Inducibility of sustained VT in patients with remote
myocardial infarction is associated with significantly increased time interval from the
peak to the end of the T-wave when compared to healthy persons. The duration of the
terminal portion of the T-wave assessed from 24-hour ECG may be the important
electrocardiographic index.
|
Key Words
|
|
T-wave interval
ventricular tachycardia, Holter ECG, myocardial infarction, OA
|
