Surawicz B
Can J Cardiol. 1986 Jul;Suppl A:71A-84A.
This review deals with the pathogenesis of ischemia-related abnormalities of ventricular repolarization. The most common repolarization abnormality during acute myocardial ischemia is the deviation of ST segment from the baseline due to diastolic and systolic currents of injury. The patterns of primary and reciprocal ST deviations during and after myocardial infarction are discussed. A very tall upright or a deeply inverted T wave, and shortened QT interval are transient phenomena followed by postischemic T wave abnormalities associated with QT lengthening. These changes are associated with lengthening of the ventricular action potentials at the border of infarction. Persistence of ST elevation after myocardial infarction is usually associated with ventricular dyskinesia. The differential diagnosis of this pattern and its possible mechanism are discussed. Also the mechanisms of ST alternans, T alternans and negative U waves, i.e. less common manifestations of myocardial ischemia are discussed. Studies of exercise-induced T wave normalization suggest that the behavior of primary T wave abnormalities after exercise does not alter the interpretation of the ischemic changes. T wave abnormalities are frequently non-specific but the post myocardial infarction T wave changes persist after administration of isoproterenol while various functional and neurogenic T wave abnormalities are corrected by isoproterenol.
本综述探讨了与缺血相关的心室复极异常的发病机制。急性心肌缺血期间最常见的复极异常是由于舒张期和收缩期损伤电流导致ST段偏离基线。文中讨论了心肌梗死期间及之后原发性和继发性ST段偏移的模式。非常高的直立或深倒置的T波以及QT间期缩短是短暂现象，随后是与QT延长相关的缺血后T波异常。这些变化与梗死边缘心室动作电位的延长有关。心肌梗死后ST段抬高持续存在通常与心室运动障碍有关。文中讨论了这种模式的鉴别诊断及其可能的机制。此外，还讨论了ST段交替、T波交替和负U波的机制，即心肌缺血较不常见的表现。运动诱导T波正常化的研究表明，运动后原发性T波异常的表现并不改变对缺血变化的解读。T波异常通常是非特异性的，但心肌梗死后的T波变化在给予异丙肾上腺素后持续存在，而各种功能性和神经性T波异常可被异丙肾上腺素纠正。
