目的探讨冠状动脉左主干病变及左主干等同病变在运动中的心电图改变及临床特征。方法采用活动平板运动试验(TET)和冠状动脉造影(CAG)对比的方法,对8例门诊疑诊冠心病、活动平板运动试验阳性者,1周内做冠状动脉造影,以冠状动脉内径狭窄≥50%为阳性。结果运动中及运动后即刻,患者均有不同程度的心绞痛症状,6例出现各种室性心律失常;心电图表现:6例为V2～6导联、2例为V4～6导联ST段水平或下斜型压低,8例均有下壁导联(Ⅱ、Ⅲ、aVF)ST段不同程度的压低。CAG中2例为LM病变,6例为LAD和LCX近端病变(双支病变)。结论运动中V2～6、Ⅱ、Ⅲ、aVF导联ST压低及aVR导联ST抬高是预测冠状动脉左主干病变及左主干等同病变的良好指标。 Objective To investigate the ECG changes and clinical features of left main coronary artery lesion and left main stem lesion during exercise. Methods TMC and CAG were compared in eight outpatients with suspected coronary heart disease and active treadmill exercise test. Coronary angiography was performed in one week. The diameter of coronary artery stenosis ≥ 50% positive. Results During and immediately after exercise, all patients had varying degrees of angina pectoris and 6 cases had various ventricular arrhythmias. The electrocardiogram showed 6 cases with V2 ~ 6 leads and 2 cases with V4 ~ 6 leads in ST segment Or down ramp type depression, 8 cases have lower leads (Ⅱ, Ⅲ, aVF) ST segment depression to varying degrees. Two of the CAGs were LM lesions, and six were LAD and LCX proximal lesions (double vessel lesions). Conclusions ST depression in leads V2 ~ 6, Ⅱ, Ⅲ, aVF and ST elevation in lead aVR during exercise are good indexes for predicting left main coronary artery disease and left main stem lesion.