体表心电图预测下壁心肌梗塞的梗塞相关动脉

目的 探讨下壁急性心肌梗塞的初始心电图能否预测梗塞相关动脉(IRA)以及合并存在的冠状动脉病变是否会改变这种预测能力.方法 102例下壁AMI病人在入院时记录标准十二导联心电图的ST段移位情况,并在住院期间行冠状动脉造影确定IRA,分析心电图ST移位与梗塞相关动脉的关系.结果(1)双左回旋支(LCX)为IRA的病人和以右冠状动脉(RC)为IRA的病人相比,前者V_1或V_2导联ST段压低的发生率明显高于后者(分别为80%和43%,P<0.01),前者I导联ST段抬高或位于等电位线的发生率也高于后者(分别为63%和27%,P<0.05);(2)根据V_1或V_2导联ST段压低判断LCX为IRA的敏感性、特异性和阴性预测值分别为83%、56%和93%.结论 下壁AMI时V_1或V_2导联ST段压低是判断LCX作为IRA敏感指标,并具有很高的阴性预测值,合并存在的冠状动脉病变不会改变这种预测能力.

Usefulness of the electrocardiogram for identifying the infarct-related artery in inferior wall acute myocardial infarction

Objective:This study compare the initial electrocardiogram(ECG) with coronary angiographic findings in patients with inferior wall actue myocardial infarction(AMI) in order to determine whether the initial ECG can predict the infarct-related artery (IRA) and whether the extent of coronary Artery disease alters the ability to predict the culprit artery. Methods:One hunhdred and twelve patients met ECG criteria for inferior wall AMI. Admission 12-lead ECG were recorded and ST-segment deflections were measured on all 12 leads. Coronary angiography were performed in all 112 patients during inhospital for determine IRA. Results: (1) Patients with LCX as IRA rather than RC were significantly more likely to have ST depression in V-l or V2(80% and 43% ,respectively) ,also the former was significantly more likely to have ST elevation or an isoelectric in 1(63% and 27% ,respectively); (2)The sensitivity ,specificity and negative predictive value of ST depression in leads V-l or V-2 for identifying the LCX as the IRA were 83% ,56% and 93% , respectirely. Conclusion:In patients with inferior wall AMI,the present of concomitant pre-cordial(V-l or V-2) ST depression was a sensitive sign of LCX occlusion and also had a high negative predictive value for regarding LCX as IRA. These predictive ability was not affected by increasing extent of underlying coronary disease.