BACKGROUND: The aim of this study was to test the hypothesis that acute myocardial ischaemia increases QT dispersion measured from the 12-lead electrocardiogram. METHODS: Incremental atrial pacing was used to induce myocardial ischaemia in 18 patients with coronary artery disease and QT dispersion was measured. Six patients with normal coronary arteries served as the control group. FINDINGS: All the patients with coronary artery disease developed angina and/or ST depression accompanied by marked increases in QT dispersion (mean increase 38 ms, 95% CI 30 to 45 ms, p < 0.001). In contrast, in the six patients with normal coronary arteries who remained without symptoms and without ST changes, there was no significant change in QT dispersion in response to pacing. Baseline QT dispersion did not distinguish those patients with coronary artery disease from those with normal coronary arteries (44 ms [95% Cl 39-49 ms] vs 40 ms [25-55 ms]), respectively. INTERPRETATION: These results demonstrate that myocardial ischaemia induced by incremental atrial pacing in patients with coronary artery disease causes an acute increase in QT dispersion. Such "inducible" QT dispersion may prove more useful than resting QT dispersion in assessing the individual risk of arrhythmic events in patients with coronary artery disease.
BACKGROUND: The aim of this study was to test the hypothesis that acute myocardial ischaemia increases QT dispersion measured from the 12-lead electrocardiogram. METHODS: Incremental atrial pacing was used to induce myocardial ischaemia in 18 patients with coronary artery disease and QT dispersion was measured. Six patients with normal coronary arteries served as the control group. FINDINGS: All the patients with coronary artery disease developed angina and/or ST depression accompanied by marked increases in QT dispersion (mean increase 38 ms, 95% CI 30 to 45 ms, p < 0.001). In contrast, in the six patients with normal coronary arteries who remained without symptoms and without ST changes, there was no significant change in QT dispersion in response to pacing. Baseline QT dispersion did not distinguish those patients with coronary artery disease from those with normal coronary arteries (44 ms [95% Cl 39-49 ms] vs 40 ms [25-55 ms]), respectively. INTERPRETATION: These results demonstrate that myocardial ischaemia induced by incremental atrial pacing in patients with coronary artery disease causes an acute increase in QT dispersion. Such "inducible" QT dispersion may prove more useful than resting QT dispersion in assessing the individual risk of arrhythmic events in patients with coronary artery disease.
Authors: Vassilios P Vassilikos; Labros A Karagounis; Apostolos Psichogios; Themistoclis Maounis; John Iakovou; Antonis S Manolis; Dennis V Cokkinos Journal: Ann Noninvasive Electrocardiol Date: 2002-01 Impact factor: 1.468
Authors: T G Lyras; V A Papapanagiotou; M G Foukarakis; F K Panou; N D Skampas; J A Lakoumentas; C V Priftis; A A Zacharoulis Journal: Clin Cardiol Date: 2003-04 Impact factor: 2.882
Authors: Vuy Hun Li; Sharmila Dorbala; Dhiraj Narula; Gordon DePuey; Jonathan S Steinberg Journal: Ann Noninvasive Electrocardiol Date: 2002-01 Impact factor: 1.468
Authors: Bülent B Altunkeser; Kurtuluş Ozdemir; Hüseyin Ozdil; Hasan Gök; Mustafa Aydin Journal: Ann Noninvasive Electrocardiol Date: 2002-07 Impact factor: 1.468
Authors: Ramazan Atak; Hasan Turhan; Alpay T Sezgin; Ozkan Yetkin; Kubilay Senen; Mehmet Ileri; Onur Sahin; Orhan Karabal; Ertan Yetkin; Emine Kutuk; Deniz Demirkan Journal: Ann Noninvasive Electrocardiol Date: 2003-04 Impact factor: 1.468
Authors: Mustafa Hassan; April Mela; Qin Li; Babette Brumback; Roger B Fillingim; Jamie B Conti; David S Sheps Journal: Pacing Clin Electrophysiol Date: 2009-09 Impact factor: 1.976