| Effects of acute myocardial ischemia on QT dispersion by dipyridamole stress echocardiography. | |
| | |
MedLine Citation:
|
PMID: 12586249 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Increased dispersion of the QT interval has been observed during pacing or exercise stress testing in patients with coronary artery disease (CAD). It has not been established whether this phenomenon is a consequence of ischemia. Therefore, we sought to evaluate whether dipyridamole-induced myocardial ischemia, as directly detected by echocardiographic monitoring of regional contractile function, would affect QT dispersion. Twenty-four patients with nonsignificant and 34 patients with significant CAD but no previous myocardial infarction underwent dipyridamole stress echocardiography while not taking medications. QT dispersion was measured on a 12-lead electrocardiogram at baseline and at various times after dipyridamole infusion. Dipyridamole infusion did not influence QT dispersion in patients without CAD. QT dispersion was similarly unaffected in patients with CAD in whom dipyridamole did not induce wall motion abnormalities. In contrast, in patients with positive dipyridamole stress test findings, QT dispersion increased from 60 +/- 17 ms at baseline to 94 +/- 25 ms during peak infusion (p <0.0001), with a time course mirroring that of development of contractile abnormalities. QT dispersion returned to 63 +/- 25 ms upon relief of ischemia by administration of aminophylline. The increase in QT dispersion was significantly related to the extent of contractile dysfunction induced by dipyridamole. Although ST-segment depression occurred in only 40% of patients with positive dipyridamole stress test findings, 88% of such patients had an increase in QT dispersion. Analysis of the receiver-operating characteristic curve showed that a QT dispersion increase of > or =20 ms identified positive findings for dipyridamole stress echocardiography with 68% sensitivity and 91% specificity. Thus, QT dispersion is acutely affected by myocardial ischemia induced by the administration of dipyridamole. Measurement of QT dispersion may improve detection of stress-induced ischemia on surface electrocardiograms. |
| | |
Authors:
|
Erberto Carluccio; Paolo Biagioli; Maurizio Bentivoglio; Myriam Mariotti; Massimo Politano; Ketty Savino; Mariagrazia Sardone; Emanuela H Locati; Giuseppe Ambrosio |
Related Documents
:
|
12604879 - Ventricular tachyarrhythmias in a canine model of lqt3: arrhythmogenic effects of sympa... 15305959 - Alteration of the qt rate dependence in anorexia nervosa. 18388029 - Qt dispersion and left ventricular hypertrophy in elderly hypertensive and normotensive... 8256749 - How to measure the qt interval--what is normal? 9391289 - Qt dispersion as a risk factor for sudden cardiac death and fatal myocardial infarction... 8780329 - Evolving role of sotalol in the management of ventricular tachyarrhythmias. 15050509 - Left ventricular thin-point detection using multidetector spiral computed tomography. 3331949 - Granulocytes as active participants in acute myocardial ischemia and infarction. 20039989 - Use of the impella microaxial blood pump for ablation of hemodynamically unstable ventr... |
Publication Detail:
|
Type: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't; Validation Studies |
Journal Detail:
|
Title: The American journal of cardiology Volume: 91 ISSN: 0002-9149 ISO Abbreviation: Am. J. Cardiol. Publication Date: 2003 Feb |
Date Detail:
|
Created Date: 2003-02-14 Completed Date: 2003-03-13 Revised Date: 2007-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 0207277 Medline TA: Am J Cardiol Country: United States |
Other Details:
|
Languages: eng Pagination: 385-90 Citation Subset: AIM; IM |
Affiliation:
|
Division of Cardiology, University of Perugia School of Medicine, Perugia, Italy. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Aged Arrhythmias, Cardiac / etiology Dipyridamole / diagnostic use* Echocardiography, Stress / standards* Electrocardiography / standards* Female Heart Conduction System Hemodynamics Humans Linear Models Male Myocardial Contraction Myocardial Ischemia / classification, complications, diagnosis*, physiopathology ROC Curve Risk Factors Sensitivity and Specificity Severity of Illness Index* Stroke Volume Vasodilator Agents / diagnostic use* |
| Chemical | |
Reg. No./Substance:
|
0/Vasodilator Agents; 58-32-2/Dipyridamole |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Cases from the Osler Medical Service at Johns Hopkins University.
Next Document: Usefulness of quantitative echocardiographic techniques to predict recovery of regional and global l...