Electorcardiographic ST-segment analysis in the characterization of myocardial ischemia and infarction.

作者：J Ross · 发表于：PubMed · 年份：1976 · 被引用次数：75 · 研究领域：Cardiac electrophysiology and arrhythmias、Cardiac Imaging and Diagnostics

The ST segments of the electrocardiogram (ECG) become elevated within 20 to 30 seconds after the onset of acute coronary occlusion and, when persistent, such changes offer a possible indirect marker of the extent and severity of myocardial ischemic injury and of eventual cell death. When ST-segment elevation on the epicardial ECG is measured 15 minutes after an acute coronary occlusion in the dog, a general correlation exists with biochemical changes, regional myocardial blood flow, and myocardial electrolyte alterations measured at 15 minutes, although when an effort is made to correlate the degree of such alterations with the magnitude of the ST-segment change there is considerable scatter. On the other hand, when the ST-segment elevation at 15 minutes is correlated with myocardial blood flow, histologic changes, and creating phosphokinase (CPK) depletion 24 hours later, the correlation is good. Possible mechanisms underlying ST-segment elevation are discussed, and data are reviewed which indicate that the epicardial ECG my be relatively insentive to subendocardial injury; in the experimental setting this problem may be partially corrected by the use of intramyocardial ECG leads. The extension of direct epicardial ECG maps to precordial ST-segment mapping poses additional problems that include reduced sensitively, problems due to reciprocal changes in the ECG at the body surface, surface contact of the electrodes, pericarditis, and individual variability in the rate of spon...