体表心电图对老年急性前壁心肌梗死左前降支闭塞部位的预测价值

Value of electrocardiogram in identifying the occlusion site of the left anterior descending coronary artery in elderly patients with anterior wall acute myocardial infarction

目的探讨体表心电图对老年急性前壁心肌梗死左前降支(LAD)闭塞部位的预测价值。方法对62例老年急性前壁心肌梗死患者的入院心电图和冠状动脉造影资料进行回顾性分析,寻找可以预测LAD闭塞部位的心电图改变。结果62例老年急性前壁心肌梗死患者均为LAD闭塞,其中近段闭塞者45例(72.6%),远段闭塞者17例(27.4%)。经χ2检验,STⅠ抬高、STaVL抬高、STaVF压低或至少2个下壁导联ST段压低等指标提示LAD近段闭塞(P均<0.05)。其中,STaVF压低或至少2个下壁导联ST段压低的特异度和阳性预测值最高,为94%左右,灵敏度以STaVL抬高最高,为56%;反之,STaVL压低和STⅢ抬高则在预测LAD远段闭塞上有显著意义(P均<0.05),特异度和阳性预测值以STaVL压低为最高,均为100%。结论急性前壁心肌梗死时,体表心电图对预测LAD闭塞部位有重要价值。

Objective To investigate the value of electrocardiogram （ECG） in identifying the occlusion site of the left anterior descending coronary artery（LAD） in elderly patients with anterior wall acute myocardial infarction （AMI）. Methods The ECGs obtained on admission and the occlusion site of LAD confirmed by coronary angiography were studied retrospectively in 62 elderly patients with first anterior wall AMI. Results Among the 62 elderly patients with anterior wall AMI, proximal occlusion of LAD（ before the origin of the first diagonal branch） were observed in 45 （ 72. 6% ） patients and distal occlusion（ after the origin of the first diagonal branch） in 17（27.4% ） patients. ST elevation in lead I or in lead aVL,ST depression in lead aVF or in I〉2 inferior leads indicated proximal occlusion of LAD（P 〈0. 05 or P 〈0. 01 ）. Among these criteria, ST depression in I〉2 inferior leads had the highest specificity and positive predictive value （PPV） of 94% and 95%, respectively, and ST elevation in lead aVL had the highest sensitivity of 56%. Contrarily, ST depression in lead aVL and ST elevation in lead IlI suggested distal occlusion of LAD（P 〈0. 05 all）. ST depression in lead aVL had the highest specificity and PPV of 100% and 100%, respectively. Conclusions ECG plays an important role in predicting the occlusion site of LAD in elderly patients with anterior wall AMI.