Importance of reciprocal ST segment depression in leads V5 and V6 as an indicator of disease of the left anterior descending coronary artery in acute inferior wall myocardial infarction.

The purpose of this study was to determine the coronary angiographic correlations (specifically disease of the left anterior descending coronary artery) of reciprocal ST segment depression appearing during inferior acute myocardial infarction. Forty six patients (41 men and five women; mean age 56 years) were allocated into two groups based on the extent of precordial ST segment depression: widespread (V1-V6) ST depression v localised (V1-V4) ST depression. Patients with no reciprocal ST depression or patients with ST depression in V1-V4 but with ST elevation in V5 and V6 (inferolateral acute myocardial infarction) were excluded. All patients were catheterised during hospital admission for infarction. Twenty four of the 28 patients with ST depression in V1-V6 had significant lesions in the left anterior descending coronary artery whereas 16 of the 18 patients with ST depression in V1-V4 had insignificant or no lesions in the left anterior descending artery. The sensitivity, specificity, and positive and negative predictive values of widespread ST depression in predicting disease in the left anterior descending coronary artery were 92%, 80%, and 86% and 89% respectively. In patients with inferior acute myocardial infarction and precordial ST depression, the extent of ST depression is of clinical significance. Widespread (V1-V6) ST depression suggests disease of the left anterior descending coronary artery, whereas localised ST depression (V1-V4) indicates its absence.     

Correlation of angiographic findings and right (V1 to V3) versus left (V4 to V6) precordial ST-segment depression in inferior wall acute myocardial infarction

This study assessed whether differences in the underlying mechanisms for various patterns of precordial ST-segment depression with inferior acute myocardial infarction (AMI) are associated with poorer prognoses. We studied 1,155 patients with inferior AMI who underwent thrombolysis in the Global Utilization of Streptokinase and TPA for Occluded arteries (GUSTO-I) angiographic substudy: those without precordial ST depression (n = 412; 35.7%), those with maximum ST depression in leads V1 to V3 (n = 547; 47.4%), and those with maximum ST depression in leads V4 to V6 (n = 196; 17.0%) on admission electrocardiogram. We compared the infarct-related artery, presence of left anterior descending or multivessel coronary artery disease, and left ventricular function among groups. Patients with maximum ST depression in leads V4 to V6 more often had 3-vessel disease (26.0%) than those without precordial ST depression (13.5%) or those with ST depression in leads V1 to V3 (15.7%; p = 0.002), and they had a lower ejection fraction (median 54% vs 60% and 55%, respectively; p <0.001). Patients with maximum ST depression in leads V1 to V3 less often had AMIs due to proximal right coronary artery obstruction (23.9%) than patients without precordial ST depression (35.2%) or those with ST depression in leads V4 to V6 (40.0%; p = 0.001) and had larger AMIs as estimated by peak creatine kinase. Different patterns of precordial ST depression are associated with distinctive coronary anatomy. ST depression in leads V4 to V6, but not V1 to V3, confers a greater likelihood of multivessel coronary artery disease.     

Concomitant left anterior descending coronary artery and right coronary artery occlusion with typical anterior ST depression and inferior ST elevation

We report the case of a 41-year-old man with acute myocardial infarction showing first ST elevation in V1-V6-DI-aVL leads followed by a typical V2-V4 ST depression (concomitant occlusion of proximal diagonal branch with an incomplete left anterior descending occlusion) and DII-DIII-aVF ST elevation. At coronary angiography, a proximal left anterior descending coronary stenosis with right coronary artery thrombosis was found.     

急性下壁心肌梗死患者心电图胸前导联ST段改变的临床意义

目的探讨急性下壁心肌梗死患者心电图胸前导联ST段改变与冠状动脉造影(CAG)所见冠状动脉病变部位的关系及其临床意义。方法 187例急性下壁心肌梗死患者,按入院时18导心电图胸前导联ST段改变分为3组,ST段无变化组(47例),ST段抬高组(16例),ST段压低组(124例);所有患者均行CAG。结果急性下壁心肌梗死伴胸前导联ST段抬高时多为右冠状动脉(RCA)近段闭塞(14例,82.3%),尤其是伴圆锥支动脉闭塞,与RCA中远端闭塞(2例,5.9%)比较差异有统计学意义(P0.01),且14例(73.7%)伴有右心功能不全和血流动力学障碍。下壁心肌梗死胸前导联ST段压低者可见于RCA、回旋支(LCX)闭塞及RCA、LCX闭塞与前降支(LAD)、对角支(D)病变的不同组合,其中LCX闭塞伴RCA病变者多表现为朐前ST V_4～V_6的压低,RCA闭塞伴LAD近端病变多有胸前ST V_1～V_6的压低,RCA伴D病变胸前ST V_1～V_3压低,与对照组比较差异有统计学意义(P0.05)。结论急性下壁心肌梗死合并胸前导联ST段抬高表明为RCA近段或丌口闭塞且多伴右心室心肌梗死和心功能不全;下壁心肌梗死伴胸前导联ST段压低提示为多支病变,ST V_1～V_3压低多伴有对角支严重狭窄,STV_1～V_6压低多伴有前降支的严重狭窄。     

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.     

Isolated ST segment depression from V2 to V4 leads, an early electrocardiographic sign of posterior myocardial infarction]

ST segment depression in leads V2 to V4 in a clinical and biochemical context of myocardial infarction is usually interpreted as a sign of non-Q wave anterior walls infarction. In order to determine if this clinical electric entity could indicate transmural posterior or posterolateral infarction, as recently suggested, we undertook a prospective study of 328 primary myocardial infarctions. Isolated ST depression in leads V2 to V4 was observed in 28 patients (8.5%). It was maximal in V3 (1.8 +/- 0.7 mm) or V4 (2 +/- 1 mm). The T wave was always positive. All these case had segmental wall motion abnormalities of the left ventricular posterolateral wall on 2D echocardiography. The Q wave confirming the transmural character of the infarct was observed in leads V7, V8 and V9 on average 33 hours after the onset of pain (10-56 hours) as did the increase in the R/S ratio in leads V1 and V2. Coronary angiography performed in 26 patients showed significant disease of the left circumflex artery in all cases. This was isolated (39%) or associated with left anterior descending (15%), right coronary artery disease (19%) or both (27%). In conclusion, isolated ST segment depression in leads V2-V4 in the clinical context of acute myocardial infarction indicates a transmural posterior localisation of the necrosis. It corresponds to reciprocal subepicardial posterior ischaemia. In cases of inferior infarction, it reflects postero-lateral extension rather than associated anterior wall ischemia.     

Clinical significance of precordial ST segment depression during acute inferior myocardial infarction

To investigate the mechanisms and clinical significance of precordial (V1-V4) ST segment depression during acute inferior myocardial infarction, stress thallium-201 scintigrams and coronary angiograms were obtained within four to eight weeks after the onset of myocardial infarction in 37 patients experiencing their first acute inferior myocardial infarction. Among 18 patients with precordial ST depression (group 1), 11 with concomitant disease of the left anterior descending artery (LAD) had positive results on exercise test, whereas in seven patients without LAD lesion, only two had positive exercise test (p less than 0.01). In 19 patients without precordial ST depression (group 2), 11 had severe stenosis in the LAD. However, among these 11 patients, only two had positive exercise tests. Patients with precordial ST depression demonstrated a higher frequency of positive exercise tests than those without it (p less than 0.01). On stress thallium-201 scintigraphy, a perfusion defect involving the inferior wall was present in all patients, but additional anterior wall ischemia was present in only five of the 18 patients in group 1. These five patients had chest pain on exercise tests and a severe stenosis greater than 90% in the LAD. There was no significant difference in the frequency of additional posterolateral wall infarction between groups 1 and 2. In 18 patients in group 1, sigma ST (total degrees of ST segment depression in leads V1, V2, V3, and V4 in the acute stage) was significantly greater in 11 patients with LAD lesion than in seven without (p less than 0.05), and sigma ST greater than five mm was observed in 12 of 13 patients who had additional anterior wall ischemia and posterolateral wall infarction on stress thallium-201 scintigraphy (p less than 0.05). Myocardial revascularization, such as aortocoronary bypass surgery or percutaneous transluminal coronary angioplasty (PTCA), was performed in six of the 18 patients in group 1 in the chronic stage, but in only one of the 19 patients in group 2. Thus, in patients with initial acute inferior myocardial infarction, those with precordial ST depression seemed to be a high-risk group. It was suggested that, during the early stage of myocardial infarction, this abnormality on electrocardiograms is related to the summation of effects of anterior wall ischemia and posterolateral wall infarction. Furthermore, the sigma ST evaluation is useful in differentiating a mirror image of inferior wall infarction from anterior wall ischemia and posterolateral wall infarction as the mechanism of precordial ST depression.     

Reciprocal ST depression in acute myocardial infarction.

ST segment depression in leads remote from those showing ST elevation during acute myocardial infarction has been attributed to benign electrical phenomena, distant myocardial ischaemia, or extensive myocardial damage. Eighty four consecutive survivors under 55 years of age with a first transmural myocardial infarction were studied. All patients had exercise tests six weeks after infarction and coronary angiography a mean of three months after infarction. Thirty eight (75%) of the 51 inferior and 19 (58%) of the 33 anterior infarcts showed reciprocal ST depression of greater than or equal to 1 mm during the acute phase. Ten (26%) of the 38 patients with inferior infarcts and reciprocal depression had ST depression in the same leads on exercise. There was concomitant disease of the left anterior descending artery in four (40%) of these 10 patients and in five (18%) of the 28 with inferior infarcts with reciprocal depression but without ST depression in the same leads on exercise. Five (26%) of the 19 patients with anterior infarcts with associated reciprocal depression and four of the 14 without reciprocal depression had important right coronary artery disease. In patients with inferior infarction important disease of the left anterior descending artery could not be predicted by ST depression in particular lead groups. Therefore reciprocal ST depression during acute myocardial infarction does not predict concomitant disease in the coronary artery supplying the reciprocal territory.     

Significance of reciprocal S-T segment depression in anterior precordial leads in acute inferior myocardial infarction: Concomitant left anterior descending coronary artery disease?

The reciprocal changes of S-T segment depression in the anterior precordial leads of the electrocardiogram in acute inferior myocardial infarction may be due to left anterior descending coronary artery disease and anterior wall ischemia. The electrocardiograms of 45 patients with acute inferior infarction who had subsequent cardiac catheterization (41 patients) or necropsy (4 patients) were examined to test this hypothesis.

Significant left anterior descending coronary artery disease (greater than 70 percent stenosis of luminal diameter) was observed in 31 (69 percent) of the 45 patients. The sensitivity, specificity and predictive value of S-T depression (1 mm or greater) in various anterior precordial leads singly or in combination was determined for this lesion. Left anterior descending coronary artery disease was present in 23 of 24 patients with S-T depression in one or more leads from V₁ to V₄ (predictive value 95 percent), and this index had the best combination of sensitivity (74 percent), specificity (93 percent) and predictive value in this group. Seven of 13 patients with left anterior descending coronary artery disease had S-T depression only in lead I or aVL, or both (sensitivity 100 percent, specificity 53 percent and predictive value 54 percent). S-T depression in any of leads I, aVL and V₁ to V₆ occurred in 37 patients, and 31 of these had left anterior descending coronary artery disease (sensitivity 100 percent, specificity 57 percent and predictive value 84 percent). The eight patients without anterior precordial lead S-T depression did not have left anterior descending coronary artery disease. Complications of infarction developed in 13 patients;S-T depression in at least one of leads V₁ to V₄ occurred in 12 (92 percent) of these 13 but in only 12 (38 percent) of 32 patients without complications.

Thus the predictive value of S-T depression in leads V₁ to V₄ (95 percent) for left anterior descending coronary artery disease is greater than the occurrence of the latter (69 percent) in all cases of acute inferior myocardial infarction (p < 0.05). S-T depression in these leads may be due not to reciprocal changes but rather to left anterior descending coronary artery disease with anterior wall ischemia. Such S-T depression is a sensitive marker for complications in these patients.     

Reciprocal ST depression in acute myocardial infarction

ST segment depression in leads remote from those showing ST elevation during acute myocardial infarction has been attributed to benign electrical phenomena, distant myocardial ischaemia, or extensive myocardial damage. Eighty four consecutive survivors under 55 years of age with a first transmural myocardial infarction were studied. All patients had exercise tests six weeks after infarction and coronary angiography a mean of three months after infarction. Thirty eight (75%) of the 51 inferior and 19 (58%) of the 33 anterior infarcts showed reciprocal ST depression of greater than or equal to 1 mm during the acute phase. Ten (26%) of the 38 patients with inferior infarcts and reciprocal depression had ST depression in the same leads on exercise. There was concomitant disease of the left anterior descending artery in four (40%) of these 10 patients and in five (18%) of the 28 with inferior infarcts with reciprocal depression but without ST depression in the same leads on exercise. Five (26%) of the 19 patients with anterior infarcts with associated reciprocal depression and four of the 14 without reciprocal depression had important right coronary artery disease. In patients with inferior infarction important disease of the left anterior descending artery could not be predicted by ST depression in particular lead groups. Therefore reciprocal ST depression during acute myocardial infarction does not predict concomitant disease in the coronary artery supplying the reciprocal territory.     

急性心肌梗死对应导联ST段变化与冠状动脉病变的关系

目的 用冠状动脉造影技术研究急性心肌梗死(AMI)对应导联ST段变化与冠状动脉病变的关系。方法136例急性心肌梗死共分五组:①组,前壁梗死(V1-6)伴有Ⅱ,Ⅲ,aVF导联ST段下移。②组,下壁梗死(Ⅱ,Ⅲ,aVF)同时伴有V1-6导联ST段下移。③组,下壁梗死(Ⅱ,Ⅲ,aVF)同时伴有I,aVL导联ST段下移。④组,前壁梗死(V1-6)未伴有其它导联的ST段变化。⑤组,下壁梗死(Ⅱ,Ⅲ,aVF)未伴有其它导联的ST段变化。所有患者均进行冠状动脉造影。结果 前壁心肌梗死伴有Ⅱ,Ⅲ,aVF导联ST段下移25例中有88%为左冠状动脉前降支病变,其中90.9%为左冠状动脉近端病变。前壁心肌梗死未伴有Ⅱ,Ⅲ,aVF导联ST段下移的36例患者中有94.4%为左冠状动脉前降支病变,两者统计无显著性差异。在下壁心肌梗死伴有V1-6导联ST段下移组22例中有81.8%为右冠状动脉病变,但同时伴有前降支病变的却有77.3%,其中单支病变仅18.2%。下壁心肌梗死未伴有V1-6导联ST段下移34例有91.2%为右冠状动脉病变,但同时伴有前降支病变的仅有32.4%,其中单支病变达52.9%。两组统计分别为P<0.001和P相似文献   

Angiographic correlates of anterior ST segment depression in acute inferior wall myocardial infarction.

This study was conducted prospectively to assess the correlation between the pattern of anterior ST segment depression on the admission electrocardiogram and the in-hospital morbidity and mortality in patients with acute inferior wall myocardial infarction. Coronary angiography was also done to assess its correlation, if any, with pattern of anterior ST segment depression. Our study cohort comprised of 165 consecutive patients with acute inferior wall myocardial infarction divided into four groups based on admission electrocardiogram. Group I (n = 33): patients with no anterior ST segment depression; group II (n = 16): patients with ST segment depression in leads V1-V3; group III (n = 71): patients with ST segment depression in leads V4-V6, I and aVF, and; group IV (n = 45): patients with ST segment depression in all anterior leads (V1-V6, I, aVL). The outcomes were analysed in terms of high grade atrioventricular block, Killip class II or higher failure, and in-hospital mortality. Coronary angiography was performed to analyse coronary anatomy. Group IV patients had increased incidence of complete heart block (37.8% vs 15.2% in the total group) (p < 0.001) and increased mortality (11.1% vs 4.2% in the total group) (p < 0.05). This group also had greater incidence of triple vessel disease (76.7%) (p < 0.001). Group II patients had greater incidence of double vessel disease (88.9%) (p < 0.05) and had no triple vessel disease. Group III patients had double vessel disease (76.5%) (p < 0.05) or triple vessel disease (23.5%) (p = NS) and no single vessel disease. Coronary angiography in group II showed greater incidence of involvement of left circumflex artery and right coronary artery while in group III there was left anterior descending artery and right coronary artery disease. We conclude that patients with anterior ST segment depression in group III and group IV categories are in high risk subset with acute inferior wall myocardial infarction.     

急性下壁心肌梗死伴有胸前导联ST段压低的临床意义

目的 分析急性下壁心肌梗死（acute inferior myocardial infarction,AIMI）伴有胸前导联ST段压低的冠状动脉病变特点及临床意义。方法 回顾分析2006年8月～2007年8月住院的AIMI患者91例。按胸前导联ST段是否压低将患者分为4组:胸前导联ST段无压低组（n=27）;胸前导联仅V1～4 ST段压低组（n=26）;胸前导联仅V5～6 ST段压低组（n=12）;广泛胸前导联ST段压低组（n=26）。结果 AIMI伴有胸前导联V1～4 ST段压低与冠状动脉多支病变呈负相关,ORⅢ=0.38,无统计学意义;AIMI伴有胸前导联V1～6 ST段压低与冠状动脉多支病变呈正相关,ORⅣ=5.25,P<0.01,有显著统计学意义。胸前导联V1～6 ST段压低组与其他组相比较,左室射血分数（LVEF）低,差异显著（P<0.05）;该组前降支病变率高（73.1%）,但与其他3组相比无统计学差异。结论 AIMI伴有胸前导联V1～6 ST段压低提示多支病变,且心功能不全发生率高。     

11例急性单纯后壁心肌梗死心电图及梗死相关动脉特点分析

目的 分析急性单纯后壁心肌梗死（不包括同时合并下壁及右室心肌梗死）的心电图及冠状动脉造影特点。方法 总结自2001年至2006年门、急诊收治的急性单纯后壁心肌梗死患者11例,随访心电图特点,并行冠状动脉造影确定梗死相关动脉。结果 11例患者除了V7-V9导联ST段有典型的弓背向上抬高1．0—2．0mm外,9例（81．8％）V1-V2导联R／S≥1,5例（45．5％）V1-V4导联ST段压低1．0—2．0mm,4例（36．4％）Ⅰ、aVL导联ST段抬高0．5-1．5mm,5例（45．5％）V5-V6导联ST段抬高0．5—1．5mm。冠状动脉造影显示梗死相关动脉均为左回旋支（LCX）。梗死部位1例在第一钝缘支（OM1）发出前,为95％管状狭窄;6例（54．5％）在OM1发出后,其中4例为100％闭塞,1例为99％次全闭塞,1例为90％长段狭窄;4例（36．4％）在OM1,其中2例为100％闭塞,1例为99％次全闭塞,1例为95％局限性狭窄。单支病变3例（27．3％）,合并左前降支（LAD）病变4例（36．4％）,合并右冠状动脉（RCA）病变2例（18．2％）,同时合并LAD及RCA病变2例（18．2％）。结论12导联心电图,如有V1-V2导联R／S≥1,V1-V4导联ST段压低等特点时,结合临床与心肌酶学改变,高度怀疑急性后壁心肌梗死,需做后壁导联和冠状动脉造影加以证实,而梗死相关动脉多为左回旋支。     

Electrocardiographic localization of the occlusion site in left anterior descending coronary artery in acute anterior myocardial infarction

BACKGROUND: The site of occlusion of left anterior descending coronary artery is important in acute anterior myocardial infarction because, proximal occlusion is associated with less favorable outcome and prognosis. The present study attempted to evaluate the electrocardiographic correlate of the location of the site of the left anterior descending coronary artery occlusion with respect to first septal perforator and/or the first diagonal branch. METHODS AND RESULTS: The study included 50 patients with a first acute anterior myocardial infarction. The electrocardiogram with the most pronounced ST segment deviation before the start of reperfusion therapy was evaluated and correlated with the left anterior descending occlusion site as determined by coronary angiography. ST segment elevation in lead aVR, ST segment depression in lead V5 and ST segment elevation in V1>2.5 mm strongly predicted left anterior descending occlusion proximal to first septal, whereas abnormal Q wave in V4-6 was associated with occlusion distal to first septal. Abnormal Q wave in lead aVL was associated with occlusion proximal to first diagonal, whereas ST depression in lead aVL was suggestive of occlusion distal to first diagonal branch. For both first septal and first diagonal, ST segment depression > or =1 mm in inferior leads strongly predicted proximal left anterior descending artery occlusion, whereas absence of ST segment depression in inferior leads predicted occlusion distal to first septal and first diagonal. All the patients were followed during their in-hospital stay (median of 7 days), during which four patients in the proximal to first septal and first diagonal group and one patient in the distal to first septal and first diagonal group died (p < or = 0.001). CONCLUSIONS: In acute myocardial infarction electrocardiogram is useful to predict the left anterior descending occlusion site in relation to its major side branches and such localization has prognostic significance.     

Precordial ST segment depression in acute inferior myocardial infarction: the importance of posterolateral wall infarction

To determine whether precordial ST segment depression during acute inferior myocardial infarction indicates posterolateral wall ischemia, anatomical predominance of coronary circulation was examined by coronary angiography and evaluated in 43 patients who experienced first acute inferior myocardial infarction. Among patients who underwent intracoronary thrombolysis within six hours from the onset of symptoms, the infarct-related artery was the right coronary artery (RCA) in 35. In addition, their early 12-lead electrocardiographic features were compared with those in eight patients having the infarct-related left circumflex coronary artery (group Cx). Thirty-five patients with RCA obstruction were categorized in four groups: Four patients with left predominant type (group L), 10 with balanced type (group B), five with right super-predominant type (group SR), and 16 with right intermediate type (group RI). Seventeen of the 21 patients in groups SR and RI demonstrated precordial ST segment depression, whereas it was present in only six of the 14 patients in groups L and B (p less than 0.05). Of the 29 patients in groups SR, Cx and RI, total ST segment depression in leads V1 through V4 (sigma ST) was greater in the 14 patients in groups L and B (p less than 0.05) than in other groups. Furthermore, in these 29, all patients in groups SR and Cx had greater sigma ST than did the patients in group RI (p less than 0.05). There was no significant difference in sigma ST between groups SR and Cx. Precordial ST segment depression did not correlate with concomitant disease of the left anterior descending artery and was not a mirror image of ST segment elevation in inferior leads. On thallium-201 scintigraphy, additional perfusion defects of the posterolateral wall were present in all eight patients in group Cx and in ten of the 21 patients in groups SR and RI. Thus, precordial ST segment depression during acute inferior myocardial infarction seemed to be affected by the pattern of coronary circulation. It was concluded that this ST depression represents more extensive involvement of the posterolateral wall in patients with right predominant coronary circulation as well as in those with left circumflex artery obstruction.     

Reciprocal changes in 12-lead electrocardiography can predict left main coronary artery lesion in patients with acute myocardial infarction

Acute left main coronary artery (LMCA) occlusion may result in acute myocardial infarction (AMI) or sudden death. ST elevation in the aVR and V1 leads is reported to be valuable in recognizing LMCA occlusion. Early recognition of electrocardiogram (ECG) changes, such as reciprocal ST depression in other leads, is helpful in averting this disaster. This study aimed to determine the reciprocal ST segment depression of 12-lead ECGs associated with acute LMCA occlusion. From January 2000 to December 2004, 61 patients who underwent emergency percutaneous coronary intervention in 3 hospitals due to AMI associated with LMCA (n = 18) and a left anterior descending coronary artery (LADCA) (n = 43) proximal lesion were selected. Reciprocal ST segment depression occurred in leads aVF, V(2), V(3), V(4), V(5), and V(6) with significantly higher incidence in the LMCA group than in the LADCA group. Stepwise linear multivariate discriminant analysis indicated that ST segment depression in leads aVF, V(2), and V(4) could distinguish the LMCA group from the LADCA group. We concluded that reciprocal ST segment depression in leads V(2), V(4), and aVF of a 12-lead ECG is an important predictor of acute LMCA occlusion.     

The significance of a persistent precordial ST segment greater than or equal to 0.1 mV depression in acute inferior myocardial infarction (coronary angiographic and ventriculographic findings)

40 patients with acute inferior myocardial infarction (MI) associated with persistent precordial ST segment depression greater than or equal to 0.1 mV underwent coronary arteriography and left ventriculography within 5-6 days of their admission. The inferior MI was the result of complete occlusion of the right coronary artery (RCA) in 38 patients and the result of complete occlusion of the posterior descending artery (PDA) coming off the circumflex artery (Cx) in two patients. 36 (90%) of the 40 patients showed one or more severe stenoses in the left anterior descending artery (LAD). 12 of the 36 patients had severe triple vessel disease. The 36 patients whose coronary arteriograms showed significant LAD stenosis had an emergency coronary artery by pass graft (CABG) operation. Soon afterwards the precordial leads were normal and the patients free of angina till their discharge from hospital. We conclude that a persistent precordial ST segment greater than or equal to 0.1 mV depression in acute inferior MI is highly predictive of significant LAD disease.     

Wellens' syndrome and other electrocardiographic changes in a patient with a left anterior descending artery subocclusion associated with a left main coronary artery subocclusion

Changing axis deviation has been reported also during atrial fibrillation or atrial flutter. Changing axis deviation has been also reported during acute myocardial infarction associated with atrial fibrillation too or at the end of atrial fibrillation during acute myocardial infarction. Patients with unstable angina have a higher incidence of left main coronary artery (LMCA) and proximal left anterior descending (LAD) coronary artery disease compared to patients with stable angina pectoris. In 1982, Wellens and colleagues described two electrocardiographic patterns that were predictive of critical narrowing of the proximal LAD artery, and were subsequently termed Wellens' syndrome. The criteria were: a) prior history of chest pain, b) little or no cardiac enzyme elevation, c) no pathologic precordial ST segment elevation, d) no loss of precordial R waves, and e) biphasic T waves in leads V2 and V3, or asymmetric, often deeply inverted T waves in leads V2 and V3. The ECG changes are best recognized outside the episode of anginal pain. Lead aVR and lead v1 ST segment elevation, during chest pain, has been reported in patients with LMCA disease with ST segment depression in leads V3, V4 and V5 (with maximal depression in V4).We present a case of changing axis deviation in a 37-year-old Italian man with a LAD coronary artery subocclusion associated with a LMCA subocclusion. This case focuses attention on the importance of the recognition of the patterns suspected for LAD coronary artery disease or for LMCA disease.     

Electrocardiogram patterns in acute left main coronary artery occlusion

Acute coronary syndrome with subtotal occlusion of the left main coronary artery is rather frequently encountered in the catheterization laboratory, whereas survival to hospital admission of sudden total occlusion of the left main coronary artery is rare. The typical electrocardiographic (ECG) finding in cases with preserved flow through the left main is widespread ST-segment depression maximally in leads V4-V6 with inverted T waves and ST-segment elevation in lead aVR. In acute myocardial ischemia without (or with minor) myocardial necrosis, the ECG pattern is transient, whereas persistent ECG changes, usually without development of Q waves, are indicative of myocardial injury. In acute total left main occlusion, severe ischemia may be manifested in the ECG by life-threatening tachyarrhythmias, conduction disturbances, and ST-segment deviation. Because of the potential for life-saving therapeutic options by invasive therapy, the ECG markers of the serious condition should be recognized by the medical profession. Left main occlusion should be suspected in severely ill patients with widespread ST-segment depressions, especially in leads V4-V6 with inverted T waves or ST elevation involving the anterior precordial leads and the lateral extremity leads I and aVL. In addition, lead aVR ST elevation accompanied by either anterior ST elevation or widespread ST-segment depression may indicate left main occlusion.