急性下壁心肌梗塞(AIMI)常有心前联 ST 段压低,但其发生机理及其含义仍不明确。有认为是下壁导联 ST 段抬高的“相反”表现,亦有认为属“真后壁”损伤及可能为前间隔缺血性损伤。Shah 等曾在下壁梗塞的急性期应用平衡法放射性核素心室造影,将有心前联 ST 段压低者与无ST 段压低者相比,发现前者左心室喷血分数比后者有更常见且更严重的降低,前者局部室壁活动的半定量指数较低,血清肌酸磷酸激酶同功酶(CPK-MB)水平较高,住院合并症亦较多。因此,急性下壁梗塞时心前区 ST 段压低似乎代表左心室更广泛 Acute myocardial infarction (AIMI) often ST-segment depression, but its mechanism and its significance remains unclear. There is the “opposite” manifestation of the ST segment elevation of the inferior leads, and some consider the “true posterior wall” injury as well as the pre-septal ischemic injury. Shah et al had used balanced radionuclide ventriculography in the acute stage of inferior wall infarction. Compared with those without ST-segment depression, there were more prevalent left ventricular ejection fraction than the latter Severe decrease, the former semi-quantitative index of local wall activity is low, serum creatine kinase kinase (CPK-MB) level is higher, hospitalization complications are more. Thus, ST-segment depression in the precordial area appears to represent a more extensive left ventricle during acute inferior wall infarction