Changes in QRS duration and R-wave amplitude in electrocardiogram leads with ST segment elevation differentiate epicardial and transmural myocardial injury

Heart Rhythm : the Official Journal of the Heart Rhythm Society
Rob F WiegerinckJuan Cinca

Abstract

Acute transmural ischemia increases QRS duration and R-wave amplitude owing to depressed intramyocardial activation. Theoretically, when myocardial injury is confined to the epicardium, the intramyocardial activation is preserved without affecting QRS duration. The purpose of this study was to distinguish epicardial from transmural myocardial injury based on the analysis of the QRS complex in leads with ST segment elevation. Electrophysiological effects of epicardial injury induced by topical application (n = 7) or intrapericardial injection (n = 10) of potassium were assessed in pigs in local electrograms recorded with needles in the left ventricle and in the peripheral 12-lead electrocardiogram (ECG), respectively, and were compared with transmural injury induced by acute left anterior descending (LAD) occlusion in the same pig. Epicardial application of 50 mM potassium induced ST segment elevation in epicardial (0.2 ± 0.06 to 0.5 ± 0.09 mV; P <.05) but not in midmyocardial local electrograms (0.1 ± 0.07 to -0.1 ± 0.09 mV). Local midmyocardial activation times were not affected by epicardial applied potassium (182 ± 5.9 vs. 183 ± 5.8 ms) but increased significantly during acute LAD occlusion (246 ± 20.9 ms; P <.01). Intraperi...Continue Reading

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Citations

Feb 5, 2016·Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups on Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology·Kumar Narayanan, Sumeet S Chugh
Jan 22, 2013·Journal of Electrocardiology·Fabrice Extramiana
Jul 27, 2010·Heart Rhythm : the Official Journal of the Heart Rhythm Society·Mark G Hoogendijk
Feb 26, 2013·Heart Rhythm : the Official Journal of the Heart Rhythm Society·Francisco J NoriegaJuan Cinca
Nov 30, 2013·The American Journal of Medicine·Xavier RosselloJuan Cinca
Apr 28, 2020·Circulation·Mori J KrantzMark C P Haigney

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