Electrocardiographic criteria for predicting total occlusion of the proximal left anterior descending coronary artery in anterior wall acute myocardial infarction

BACKGROUND: Patients with occlusion of the left anterior descending coronary artery (LAD) proximal to both the first septal branch and the first diagonal branch may benefit most from early reperfusion therapy due to extensive area at risk. HYPOTHESIS: The aim of the study was to examine whether 12-lead electrocardiograms (ECGs) in the acute phase of acute myocardial infarction (AMI) could identify total occlusion of the LAD proximal to both the first septal and the first diagonal branch. METHODS: A 12-lead electrocardiogram was recorded on admission in 128 patients with anterior AMI within 12 h from symptom onset. Patients were divided into three groups according to the culprit lesion: 33 patients had total occlusion of the LAD proximal to both the first septal perforator and the first diagonal branch (Group P), in 51 it was proximal to either the first septal perforator or the first diagonal branch (Group D-a), and in 44 it was distal to both the first septal perforator and the first diagonal branch (Group D-b). RESULTS: Sensitivity and specificity of a greater degree of ST-segment depression in lead III than that of ST-segment elevation in lead aVL were 85 and 95%, respectively, which was better than the results derived by all other ECG criteria (p< 0.001). CONCLUSIONS: We conclude that a greater degree of ST-segment depression in lead III than that of ST-segment elevation in lead aVL is a useful predictor of proximal LAD occlusion in patients with anterior AMI.     

常规心电图对急性前壁心肌梗死时前降支闭塞部位预测价值的临床研究

目的探讨急性前壁心肌梗死时的常规心电图（ECG）对前降支（LAD）闭塞部位的预测价值。方法根据冠状动脉造影的结果，以第一间隔支（S1）为标志将患者分为S1近端病变（PS）组（61例）和S1远端病变（DS）组（40例）。分别测量常规ECG12导联ST段的偏移程度及出现的频率，以计算、比较两组之间的差异及其对近、远段病变部位的预测性诊断价值。结果（1）各导联诊断LAD近端病变的敏感性和特异性分别为：aVR导联ST段抬高为43％和85％（P=0．004）；aVL导联ST段抬高≥1．5mm为16％和97％（P=0．031）；Ⅱ导联ST段下移≥1．0mm为39％和85％（P=0．009）；Ⅲ导联ST段下移≥2．0mm为23％和98％（P=0．005）；aVF导联ST段下移≥1．0mm为38％和88％（P=0．006）；V5导联ST段下移为20％和86％（P=0．037）；aVR导联ST段抬高同时伴V5导联ST段下移为18％和100％（P=0．005）；aVR导联ST段抬高同时伴V6导联ST段下移为30％和93％（P=0．008）；（2）各导联诊断LAD远端病变的敏感性和特异性分别为：Ⅲ导联ST段居于等电位线或抬高为53％和90％（P=0．000）；V5导联ST段抬高≥1．5mm为50％和82％（P=0．001）；（3）近、远端患者的梗死面积和心功能水平未见明显差异。结论（1）aVR导联ST段抬高同时出现V5、V6导联ST段下移；下壁导联Ⅱ、Ⅲ、aVF导联ST段明显下移（Ⅱ，aVF导联ST段下移≥1．0mm，STⅢ下移≥2．0mm）以及Ⅰ，aVL导联ST段抬高，尤其是aVL导联ST段抬高≥1．5mm均提示LAD近端病变。（2）下壁导联（尤其是Ⅲ导联）ST段居于等电位线或升高，V5导联ST段抬高≥1．5mm均提示LAD远端病变。     

体表心电图在预测急性心肌梗死左前降支病变部位的价值

目的:探讨体表心电图在预测急性心肌梗死(AMI)左前降支病变部位的价值。方法:分析47例梗死相关动脉为左前降支的AMI患者梗死部位与体表心电图的关系。结果:I、aVL、aVR导联ST抬高及Ⅲ导联ST降低在预测AMI左前降支病变部位的价值各不相同,aVL导联ST抬高的敏感性最高,aVR导联ST抬高的特异性最强,但各组间差异无统计学意义。进行Logistic回归分析后,只有aVL导联ST抬高与左前降支近端病变有相关性,其优势比(OR值)为5.778。结论:I、aVL、aVR导联ST抬高及Ⅲ导联ST抬高是预测AMI中左前降支病变部位的较好指标,但以aVL导联ST抬高最好。     

Value of the electrocardiogram in localizing the occlusion site in the left anterior descending coronary artery in acute anterior myocardial infarction.

OBJECTIVES: The study assessed the value of the electrocardiogram (ECG) as predictor of the left anterior descending coronary artery (LAD) occlusion site in relation to the first septal perforator (S1) and/or the first diagonal branch (D1) in patients with acute anterior myocardial infarction (AMI). BACKGROUND: In anterior AMI, determination of the exact site of LAD occlusion is important because the more proximal the occlusion the less favorable the prognosis. METHODS: One hundred patients with a first anterior AMI were included. The ECG showing the most pronounced ST-segment deviation before initiation of reperfusion therapy was evaluated and correlated with the exact LAD occlusion site as determined by coronary angiography. RESULTS: ST-elevation in lead aVR (ST elevation(aVR)), complete right bundle branch block, ST-depression in lead V5 (ST depression(V5)) and ST elevation(V1) > 2.5 mm strongly predicted LAD occlusion proximal to S1, whereas abnormal Q-waves in V4-6 were associated with occlusion distal to S1 (p = 0.000, p = 0.004, p = 0.009, p = 0.011 and p = 0.031 to 0.005, respectively). Abnormal Q-wave in lead aVL was associated with occlusion proximal to D1, whereas ST depression(aVL) was suggestive of occlusion distal to D1 (p = 0.002 and p = 0.022, respectively). For both the S1 and D1, inferior ST depression > or = 1.0 mm strongly predicted proximal LAD occlusion, whereas absence of inferior ST depression predicted distal occlusion (p < or = 0.002 and p < or = 0.020, respectively). CONCLUSIONS: In anterior AMI, the ECG is useful to predict the LAD occlusion site in relation to its major side branches.     

Prediction of the site of total occlusion in the left anterior descending coronary artery using admission electrocardiogram in anterior wall acute myocardial infarction

In anterior acute myocardial infarction, ST elevation in aVL and ST depression in II, III, and aVF predict a culprit lesion in the left anterior descending artery proximal to the origin of the first diagonal branch, with good specificity and positive predictive value. Inferior ST depression is not related to remote ischemia but represents an electrocardiographic phenomenon reciprocal to ST elevation in aVL.     

Electrocardiographic prediction of the site of lesion in the anterior descending artery in acute myocardial infarction

INTRODUCTION AND OBJECTIVES: The goal of this study was to analyze the value of electrocardiography in predicting the site of the lesion in the left anterior descending coronary artery, in relation to the first septal and the first diagonal branches, in patients with acute anterior myocardial infarction. METHOD: Ninety consecutive patients who were admitted to the coronary unit with acute anterior myocardial infarction from July 1998 to May 2000 were studied retrospectively. The electrocardiographic changes were analyzed and correlated with the site of the lesion in the anterior descending artery, as determined by coronary angiography. RESULTS: The most useful parameters in predicting the site of the lesion in the left anterior descending coronary artery in acute anterior myocardial infarction are: 1) For lesions proximal to the first septal branch, ST-segment elevation in aVR (p < 0.001) and the absence of Q wave in V4-V6 (p = 0.01). 2) For lesions proximal to the first diagonal branch, abnormal Q wave in aVL (p = 0.01) and ST depression in III (p = 0.05). 3) For lesions proximal to both the first septal and first diagonal branches, ST elevation in aVR (p < 0.001), abnormal Q wave in aVL (p = 0.02), and absence of Q wave in V4-V6 (p = 0.01). 4) For lesions distal to both the first septal and first diagonal branches, abnormal Q wave in V4-V6 (p = 0.001) and absence of ST depression in III (p < 0.001). CONCLUSIONS: In acute anterior myocardial infarction, electrocardiography is useful for predicting the site of the lesion in the left anterior descending coronary artery in relation to the first septal and the first diagonal branches.     

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

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。     

Usefulness of the electrocardiogram in predicting the occlusion site in acute anterior myocardial infarction with isolated disease of the left anterior descending coronary artery

INTRODUCTION AND OBJECTIVES: In acute anterior myocardial infarction (AMI), the site of occlusion in the left anterior descending coronary artery (LAD) is related to the extension of myocardial necrosis and the prognosis. The aim of this study was to assess the value of the electrocardiogram (ECG) as a predictor of the LAD occlusion site in patients with anterior AMI. METHODS: Forty-five consecutive patients with a first anterior AMI and isolated disease of the LAD were included. We evaluated retrospectively the ECG with the most pronounced ST-segment changes before fibrinolysis and correlated the findings with the site of LAD occlusion in angiography before hospital discharge in relation to the first dominant septal and first diagonal branch: first septal affected (S), first diagonal affected (D), both affected (S + D), or neither affected were considered. RESULTS: ST depression in leads II, III, or aVF strongly predicted proximal LAD occlusion in S + D, S, and D (p = 0,003, p = 0,04, and p = 0,02, respectively). ST elevation in leads II, III, or aVF was observed only in the presence of wrap-around LAD and was related with occlusion distal to the first diagonal branch. ST elevation > or = 3 mm in lead V1 was a specific predictor of occlusion proximal to first septal (S, p = 0,01). ST elevation in aVR was associated with proximal LAD occlusion in S + D and S (p = 0,03 and p = 0,03, respectively) and absence of coronary collateral circulation. CONCLUSIONS: In anterior AMI and isolated LAD disease, the ECG can be useful in predicting the LAD occlusion site in relation to its major side branches.     

心电图诊断冠脉前降支闭塞部位的研究

目的 探讨前壁急性心肌梗死(AMI)体表心电图(ECG)预测前降支(LAD)阻塞部位的准确率.方法 对2010年6月至2013年12月在井冈山大学附属医院心血管科145例前壁AMI患者ECG预测阻塞部位与冠状动脉造影术(CAG)显示阻塞部位进行对比分析.以大对角支(LD)或第一对角支(D1)为界划分LAD为近远段.结果 前间壁AMI 20例,LAD阻塞部位均在LD或D1开口以远.前壁AMI、前壁+下壁AMI共67例LAD阻塞部位大多在LD或D1开口以远(80.6％ vs.86.6％),两种分界法差异无统计学意义(p=0.351).广泛前壁、广泛前壁+高侧壁、前壁+高侧壁AMI共58例LAD阻塞部位多发生LD或D1开口以近(96.55％vs.72.4％),两种分界法差异有显著的统计学意义(p=0.000),以LD为界有较高的阳性预测值(96.55％ vs.72.41％ p=0.000)、特异度(97.3％ vs.83％,p=0.003),心电图判断LAD近段阻塞以LD分界更准确.结论 前壁AMI心电图对预测LAD阻塞部位有较高的准确率.     

Double vessel acute myocardial infarction showing simultaneous total occlusion of left anterior descending artery and right coronary artery

Simultaneous double vessel acute myocardial infarction (AMI) is extremely rare and usually has poor clinical outcomes. Management of this complicated condition is challenging and time-limited. The case of a 46-year-old Taiwanese man with simultaneous anterior and inferior wall AMI is reported. Rapid deterioration of clinical condition with ventricular fibrillations (VF), cardiogenic shock and asystole developed before catheterization. Coronary angiogram revealed simultaneous total occlusion of left anterior descending (LAD) and right coronary arteries (RCA). Frequent VF attack was still noted after diagnostic catheterization. After cardiopulmonary resuscitation, immediate percutaneous coronary intervention of the LAD and RCA, and intra-aortic balloon counterpulsation was inserted. Due to intractable heart failure and cardiogenic shock, extracorporeal membrane oxygenation was performed. Rabdomyolysis with acute renal failure was also noted with hemodialysis treatment. Thirty-one days after hospitalization, he was discharged with a New York Heart Association functional class III heart failure, without hemodialysis.     

Transient myocardial bridging of the left anterior descending coronary artery in acute inferior myocardial infarction

We observed transient myocardial bridging of left anterior descending coronary artery (LAD) in 18.75% (12 of the total 64) of the patients during acute inferior myocardial infarction (MI). Myocardial bridging occurred only in the acute phase of inferior MI and not in the chronic phase. In the acute phase of inferior MI, compensatory hypercontraction of the anterior wall is assumed to occur in response to the decrease in the movement of the infarct-related walls. In the chronic phase, disappearance of the myocardial bridging observed due to the resolution of compensatory anterior wall hypercontraction, as a result of the reperfusion of infarct-related coronary artery. Most of the myocardial bridges seen in autopsy series are not seen angiographically. Variation at angiography may in part be attributable to small and thin bridges causing little compression. Adrenergic stimulation or afterload reduction by nitroglycerin facilitates diagnosis of myocardial bridging by increasing coronary compression. Both of these conditions are almost always present in acute MI. We concluded that transient myocardial bridging of LAD can be observed in some patients with acute inferior MI during acute stage.     

A case of acute myocardial infarction due to simultaneous occlusion of the right coronary artery and left anterior descending coronary artery

We reported a rare case of a 53-year-old man who experienced acute myocardial infarction due to simultaneous occlusion in the right coronary artery and the left anterior descending coronary artery. He also experienced thromboembolisms on several occasions. So anticoagulant therapy is necessary for patients with exceedingly poor LV function.     

Electrocardiographic patterns of proximal left anterior descending artery occlusion in ST-elevation myocardial infarction may be modified by 3-vessel coronary artery disease

BackgroundThe electrocardiographic (ECG) pattern of ST-segment deviation in myocardial infarction is integral to the proper assessment of the location, extent, and functional significance of the infarct but may be modified by the underlying coronary artery anatomy.MethodsWe describe the ECG findings in 2 cases of proximal left anterior descending (LAD) artery occlusion in ST-elevation myocardial infarction (STEMI) associated with 3-vessel coronary artery disease.ResultsBoth patients had atypical ECG patterns of ST-segment elevation in leads V₂, I, and aVL and ST-segment depression with positive T waves suggestive of extensive subendocardial ischemia in leads II, III, aVF, and V₃ through V₆; acute proximal LAD occlusion and concomitant 3-vessel coronary artery disease were observed angiographically.ConclusionElectrocardiographic changes in proximal LAD STEMI may be modified by the presence of significant atherosclerotic disease elsewhere in the coronary vasculature. Recognition of this ECG pattern may aid the clinician in the rapid identification of high-risk STEMI.     

Electrocardiographic manifestations of proximal left anterior descending artery occlusion

We report the case of a 51-year-old woman who presents with a 2-week history of episodes of pressure like chest pain. The initial electrocardiogram was not indicative of myocardial ischemia or infarction and the cardiac enzymes remained normal during the initial hospital day. However, the precordial T waves inverted and progressively deepened on the second hospital day and the patient underwent cardiac catheterization with percutaneous coronary angioplasty and stent placement of the left anterior descending coronary artery with good results. The postprocedure electrocardiogram showed complete resolution of the inverted precordial T waves. The development of new T-wave inversions in the precordial leads of patients presenting with unstable angina is predictive of significant stenosis of the left anterior descending coronary artery. This subgroup of patients has a poor prognosis if medical therapy alone is instituted. Early cardiac catheterization and revascularization is recommended for these patients. Evidence has shown that 75% patients with these electrocardiogram changes who are not revascularized developed extensive anterior wall infarction within a few weeks.     

Relation of ST-segment changes in inferior leads during anterior wall acute myocardial infarction to length and occlusion site of the left anterior descending coronary artery

We investigated the relation between left anterior descending (LAD) coronary artery morphology and inferior lead ST-segment changes to elucidate the clinical significance of such changes in 159 patients with anterior wall acute myocardial infarction (AMI). Patients with 1-vessel LAD artery lesions were divided into an ST depression group (n = 40), an ST elevation group (n = 25), and a no-ST-change group (n = 94) based on ST-segment changes in the inferior leads. The relation between each group and the infarct-related lesion and the presence of a wrapped LAD artery was then investigated. The percentage of patients with the infarct-related lesion in the proximal LAD artery was significantly higher in the ST depression group and significantly lower in the ST elevation group. The percentage of patients with a wrapped LAD artery was significantly higher in the ST elevation group and significantly lower in the ST depression group. The wall motion index determined echocardiographically was significantly higher in the ST depression group and the no-ST-change group than in the ST elevation group. Our findings suggest that inferior lead ST-segment changes during anterior wall AMI arise as a result of competition between reciprocal changes caused by high lateral wall AMI due to lesions of the proximal LAD artery, which depress the ST segment, and inferoapical wall AMI due to a wrapped LAD artery, which elevates the ST segment. In patients with no ST-segment changes, echocardiography was useful for distinguishing the amount of affected LAD artery territory.     

急性前壁心肌梗死时心电图预测左前降支阻塞部位的临床意义

目的 :探讨心电图ST段改变与冠状动脉病变部位的关系。方法 :对 76例急性前壁心肌梗死 (AA MI)病例进行回顾性分析。结果 :① 76例患者中 ,4 2例为前降支单支病变。 34例为前降支并发多支血管病变。根据前降支不同病变部位分为两组 :前降支近段病变组 (PD)、前降支远段病变组 (DD) ,两组间比较 :PD组在Ⅰ、aVL导联出现ST段抬高明显增加 ,差异有非常显著性意义 (P <0 .0 1) ,在Ⅱ、Ⅲ、aVF导联ST段压低明显增加 ,差异有显著性意义 (P <0 .0 5 )。② 34例前降支并发多支血管病变中 ,PD组同DD组比较 ,Ⅰ、aVL导联ST段抬高≥ 1mm者明显增加 ,Ⅲ、aVF导联ST段压低≥ 1mm者明显增加。Ⅱ导联压低≥ 1mm者有增加趋势 ,但差异无显著性意义 (P >0 .0 5 )。结论 :AAMI前降支阻塞时行心电图检查可以预测病变部位 ,Ⅰ、aVL导联ST段抬高 ,Ⅱ、Ⅲ、aVF导联ST段下移同前降支近段病变存在良性相关性。可视为对应性改变。前降支远段病变时Ⅱ、Ⅲ、aVF导联ST段常常在等电位线或抬高