临床心电图学的一个最早发现是心绞痛发作时所记录的图形示有可逆性ST段压低。根据这一发现,设计了“两级梯试验”,让病人作短暂运动,运动后立即记录心电图。根据对ST段反应正常或异常病人的随访研究,两级梯试验被普遍接受作为检查心肌缺血的一种试验,并制定了阳性和阴性反应的标准。近十年来,技术上的进步以及活动平板与踏车运动试验的采用,使之不仅能在运动后记录心电图,而且在运动时也能记录。运动可以定量,逐渐增加运动负荷至生理疲劳点,试验的终点系预先选定(例如症状限制或心率限制)。选择性冠状动脉造影的普遍应用,则提供了一个独立的标准,它可用以评价运 One of the earliest findings of clinical electrocardiography was that the graphs recorded during angina episodes showed reversible ST-segment depression. Based on this finding, a “two-step ladder test” was designed to allow patients to make short-term movements and record the ECG immediately after exercise. Based on follow-up studies of patients with normal or abnormal ST-segment responses, a two-step ladder test is commonly accepted as a test to examine myocardial ischemia and sets the standard for both positive and negative reactions. In the last decade, advances in technology and trials of treadmill exercise and treadmill exercise have made it possible to record electrocardiograms not only after exercise but also during exercise. Exercise can be quantitative, and gradually increase the exercise load to physiological fatigue point, the end of the trial is pre-selected (such as symptom limits or heart rate limits). The widespread use of selective coronary angiography provides an independent standard that can be used to evaluate