Acute myocardial infarction with significant left main coronary artery stenosis, significant 3-vessel coronary artery disease and elevated troponin-I at admission

Exercise-induced ST-segment elevation in lead aVR accompanied by ST-segment elevation in lead V1 might be a specific finding of left main coronary artery (LMCA) stenosis. Lead aVR and lead v1 ST segment elevation has been reported, during an attack of chest pain, in patients with LMCA disease with ST segment depression in leads V3, V4 and V5 (with maximal depression in V4). ST-segment elevation in lead aVR in patients with angina at rest can be related to transmural ischemia of the basal part of the interventricular septum, frequently due to LMCA or multivessel coronary disease too. 3-vessel coronary artery disease (CAD) and LMCA disease show a frequent combination of leads with abnormal ST segments during chest pain with ST-segment depression in leads I II V4-V6, and ST-segment elevation in lead aVR. When ST-segment status in lead aVR combines with troponin T, ST-segment elevation in lead aVR and positive troponin T on admission are useful predictors of LMCA or 3-vessel CAD. We present a case of acute myocardial infarction with significant left main coronary artery stenosis, significant 3-vessel coronary artery disease and elevated troponin I at admission in an 83-year-old Italian woman. Also this case focuses attention on the importance of the recognition of the patterns suspected for LMCA and/or 3-vessel coronary disease.     

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V(1).

OBJECTIVES: We sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction. BACKGROUND: Prediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis. METHODS: We studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group). RESULTS: Lead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 +/- 0.13 mV) than in the LAD group (0.04 +/- 0.10 mV). Lead V(1) ST segment elevation was lower in the LMCA group (0.00 +/- 0.21 mV) than in the LAD group (0.14 +/- 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V(1) ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation. CONCLUSIONS: Lead aVR ST segment elevation with less ST segment elevation in lead V(1) is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient's clinical outcome.     

急性心肌梗死左主干与前降支近段病变心电图ST段压低的对照分析

目的探讨12导联心电图ST段压低在急性心肌梗死左主干与前降支近段病变鉴别中的价值。方法选取因急性心肌梗死住院的患者,依冠状动脉造影结果,分为冠状动脉左主干病变(LM组)和左前降支近端病变(LAD组)。回顾性分析患者入院即刻的12导联心电图,比较两组ST段压低改变的特点。结果入选符合标准的患者共74例,LM组15例,LAD组59例。LM组Ⅰ、Ⅲ、aVL和aVF导联ST段压低比例显著高于LAD组(P均<0.05),V2～6ST段压低比例两组亦有差异(P均<0.01)。同时,V2～6导联ST段改变值两组亦有差异。多元分析表明Ⅲ、V2和V6导联ST段压低对急性左主干病变有预测价值(P均<0.001),其诊断的敏感度为26.7%、特异度100%、阳性预测值100%和准确度85.1%。结论Ⅲ、V2和V6导联ST段压低有助于鉴别急性左主干与左前降支近段病变。     

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。     

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.     

冠状动脉前降支闭塞致急性心肌梗死的心电图ST段偏移特点分析

目的探讨冠状动脉前降支(LAD)单支闭塞所致急性心肌梗死(AMI)的心电图(ECG)特点。方法回顾性分析51例LAD急性闭塞所致AMI患者心电图ST段改变与冠状动脉造影结果。结果 V_2导联ST段抬高<0.2 mV预测LAD远段闭塞敏感度为52.9%,特异度为88.2%,在胸导联ST段抬高的情况下,特异度增高(96.2%)。V_6导联ST段压低预测LAD近段闭塞敏感度为26.5%,特异度100%,在胸导联ST段抬高的情况下,V_1导联ST段抬高≥0.2 mV预测LAD近段闭塞敏感度53.8%,特异度88.9%。下壁导联Ⅱ、Ⅲ、aVF ST段压低预测LAD近段闭塞特异度较高,Ⅲ、aVF导联组合较Ⅱ、Ⅲ、aVF导联组合判断LAD近段闭塞特异度及阳性预测值高。结论 V_1导联ST段抬高、V_6导联ST段压低、下壁导联ST段压低有助于判断LAD近段闭塞,V_2导联ST段抬高<0.2 mV有助于判断LAD远段闭塞。     

Vasospastic total occlusion at the left main tract in a single coronary artery.

A 64-year-old man was admitted to hospital under the suspicion of unstable angina pectoris. Coronary angiography showed that he has a single coronary artery originating from the right coronary artery (RCA) without significant fixed stenosis. Acetylcholine was superselectively infused into the left main coronary artery (LMCA), and confirmed the coronary vasospastic occlusion associated with chest pain and elevation of the ST-segment in the precordial leads. This is the first report of the induction of a totally occlusive spasm of the LMCA of a patient with a RCA type single coronary artery, and this case suggests that spasm of the aberrant coronary artery is a potential mechanism for sudden death in patients with a single coronary artery.     

246例回旋支不同节段闭塞的心电图特点

目的探讨回旋支闭塞中不同节段,不同优势型,多支病变对心电图变化的影响。方法本研究共入选246例发生急性LCX闭塞的患者（其中男187例,女59例）,根据冠脉造影结果将患者根据冠脉优势型、单支、多支、合并LAD、RCA分组,结合年龄、性别及相关危险因素,对比分析心电图改变与冠脉造影结果及临床特点的关系。结果回旋支闭塞心电图变化受不同冠脉优势型影响,Ⅱ、Ⅲ、aVF、V7~V9导联ST段抬高常见于左优势型的LCX闭塞。V1~V3导联ST段压低常见于均衡型的LCX闭塞,Ⅰ、aVL导联ST段抬高在各优势型中无特异性。在单支LCX闭塞中,V1~V3导联ST段压低常见于近段闭塞,Ⅱ、Ⅲ、aVF导联ST段抬高常见于远段闭塞,V7~V9导联ST段抬高与Ⅰ、aVL导联ST段抬高在各节段闭塞的心电图中无特异性。合并多支病变时LCX心电图变化与单纯LCX闭塞存在差异,在LCX近段闭塞中,合并多支病变的患者更易出现V7~V9导联ST段抬高,单支病变者心电图易出现V1~V3导联ST段压低,在LCX中段闭塞的患者中,单支病变与多支病变的心电图改变大致相同。在LCX远段闭塞的患者中,多支病变患者出现V1~V3导联ST段压低可能性较大。OM闭塞在单支及合并多支病变时的心电图差异无明显统计学意义。在合并LAD或RCA病变的LCX闭塞患者中,心电图改变无明显差异。结论心电图对诊断梗死相关动脉为回旋支的急性心肌梗死有重要的预测价值,结合病史及相关一般资料可对急性心肌梗死患者的预后进行评估。     

Precordial T-wave polarity changes in acute inferior infarction. A poor indicator of associated disease of the left anterior descending coronary artery

T-wave polarity in V1 to V3 was examined in 70 patients with acute inferior wall myocardial infarctions (IWMI) as an indicator of significant disease in the left anterior descending coronary artery (LAD). Fifty-three percent (37/70) had precordial T-wave inversions, and of these 38 percent (14/37) had angiographically significant LAD disease. Conversely, 47 percent (33/70) had upright T waves in V1 to V3, and of these, 52 percent (17/33) had significant LAD disease. Likewise, 41 percent of the patients with ST segment depression in V1 to V3 had significant LAD disease, while 50 percent of those with isoelectric ST segments were similarly affected. Finally only 39 percent of those patients with both precordial ST segment depression and T-wave inversion had significant LAD disease. We conclude that neither anterior ST depression, T-wave inversion, nor a combination of both is a sensitive or specific indicator of LAD disease in patients with acute IWMI.     

Potential risk of provisional stenting in left main coronary artery bifurcation in multivessel‐related acute coronary syndrome

We present a case of an elderly man suffering from an acute coronary syndrome (ACS) with preshock vital signs and remarkable ST–T wave depression in leads V4–V6, and ST elevation in lead aVR. Coronary angiography showed total occlusion of the right coronary artery (RCA) and impending occlusion in the distal left main coronary artery (LMCA) with a tandem lesion in the proximal left anterior descending artery (LAD). After insertion of an intra‐aortic balloon pump both the LAD and left circumflex artery (LCX) were dilated alternatively; and cross‐over stenting in the LMCA bifurcation was subsequently performed. However, total occlusion of the LCX occurred and it caused acute hemodynamic collapse and ventricular fibrillation storm. Immediate installation of percutaneous cardio‐pulmonary support system allowed stent deployment to be performed in the RCA and subsequent reopening of the LCX that led to a return to sinus rhythm. The patient recovered almost normal left ventricular wall motion and previous activity without any neurological deficit within 2 weeks. Provisional stenting in ACS in the LMCA bifurcation with multivessel disease has a potential risk of acute hemodynamic collapse; a planned two‐stent deployment strategy may assure a higher rate of safety in such cases. © 2011 Wiley‐Liss, Inc.     

Class I antiarrhythmic drug and coronary vasospasm-induced T wave alternans and ventricular tachyarrhythmia in a patient with Brugada syndrome and vasospastic angina

A 50-year-old man presented with a history of transient chest pain and palpitations. The 12-lead ECG at rest showed normal sinus rhythm. A slight ST segment elevation was observed in leads V1 to V3. During hospitalization, atrial fibrillation developed, and oral pilsicainide was administered. Thirty minutes after the drug was given, the ECG showed marked ST segment elevation in leads V1 to V3, and T wave alternans became visible in leads V2 and V3. Self-terminating ventricular tachycardia was initiated following frequent ventricular premature complexes, which showed a left bundle branch block pattern. The coronary angiogram was normal, but in the provocation test of vasospastic angina, acetylcholine administration into the left coronary artery resulted in complete occlusion of the left anterior descending and circumflex arteries. Marked ST segment elevation developed in leads I, aVL, and V3 to V6 concomitant with visible QT/T alternans in leads V4 and V5, and ventricular tachyarrhythmia was initiated. Brugada syndrome and vasospastic angina coexisted in this patient, and T wave alternans can be used as a predictor of ventricular tachyarrhythmias in such patients.     

Clinical presentation and prognosis of left main coronary artery disease in the 1980s

Clinical presentation and course were studied in 127 consecutive patients with angiographically proven left main coronary artery disease. Mean age was 62 (37-79) years. Thirteen patients (10%) had no history of chest pain, seven (5%) had atypical chest pain, and the remaining 107 (85%) typical angina pectoris. Eighty-two patients (65%) had unstable angina, 73 had suffered a myocardial infarction (MI) in the past, and 50 (68%) had post MI angina pectoris. The electrocardiogram was analysed in 102/125 patients during an episode of chest pain and also when they were without chest pain. Outside an episode of chest pain the ST segment was normal in 42 patients (32%), the T wave was normal in 50 patients (38%) and both the ST and T were normal in 33 patients (25%). During chest pain all patients had an abnormal ECG, the most frequent pattern being ST segment depression in leads V3, V4 and V5 (with maximal depression in V4), and ST segment elevation in leads V1 and aVR. The average number of leads with ST-T abnormalities was 6.4. A symptom-limited exercise test on a treadmill with 12-lead ECG monitoring was performed in 89 patients. The exercise test was abnormal in 88 patients (99%), most of whom (74 patients) were already in the first or second stage of the Bruce protocol. The most frequently observed abnormality was ST segment depression of 2 mm or more in leads V4, V5, and V6, and ST segment elevation in leads V1 and aVR. The systolic blood pressure during exercise fell or remained at the same level in 38 patients (43%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Unusual ST-t changes in Ebstein's anomaly with occlusion of a nondominant coronary artery

We present a case report of a patient of Ebstein's anomaly presenting with unusual ECG changes during acute coronary syndrome. The patient had undergone radiofrequency ablation of right posteroseptal accessory pathway. Two years later, he presented with acute chest pain. His ECG revealed ST elevation of 6-7 mm in leads III, aVF. V3R and V1-V4 with atrioventricular dissociation. He was thrombolysed for the same. He subsequently underwent an angiogram for continuing angina. His angiogram showed a nondominant right coronary artery with a 95% stenosis. The left circumflex artery was dominant but without any stenosis. The left anterior descending artery was also normal. Angiogplasty and stenting were done for the right coronary artery lesion and the patient did well on follow-up. The ST segment elevation in the anterior precordial leads resulting from occlusion of a nondominant right coronary artery is unusual. The possible reason for this is the isolated right ventricular infarction in the absence of any left ventricular infarction. Thus the electrical current of injury resulting from the right ventricular infarction was unopposed by any counterbalancing current of injury from the inferior surface of the left ventricle.     

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.     

严重冠脉病变的心电图分析

目的分析左主干、前降支近端或三支病变冠心病心绞痛患者的心电图改变。方法13例冠脉造影诊断为左主干、前降支近端或三支病变的患者,对其静息时、心绞痛发作时心电图有无aVR、V1导联的ST段抬高及临床资料进行分析。结果胸痛发作时11例出现了aVR、V1导联典型改变,静息时2例aVR、V1导联改变。结论心电图aVR、V1导联ST段抬高,尤其STaVR〉STV1,V4～V6导联ST段下移,合并Ⅱ、Ⅲ、aVF导联或Ⅰ、Ⅱ导联ST段下移与冠脉左主干、前降支近端严重狭窄及三支病变有良好的相关性。     

Optimal ECG monitoring during percutaneous transluminal coronary angioplasty of the left anterior descending artery

During percutaneous transluminal coronary angioplasty (PTCA) frontal ECG leads are routinely monitored. The detection of ST segment deviation during the procedure is important for decisions regarding guiding catheter seating and the timing of balloon inflation and deflation. ST segment deviation appears on intracoronary electrograms in the absence of changes on the surface ECG in many patients, while the reverse is true in some individuals. When a precordial lead is employed, V5 or V6 is most commonly selected. The surface ECG leads most sensitive for monitoring ischemia during left anterior descending angioplasty are not known. In nine lead surface ECGs recorded during balloon inflation, a small degree of ST segment elevation occurred in leads I, aVL, and V5. Lead V2 demonstrated an increase in ST displacement from 0.0 ± 0.03 mV to 0.29 ± 0.25 mV during coronary occlusion (p<0.01). We conclude that if V5 or V6 is used as a single precordial lead, surface ECG alterations are easily overlooked. During left anterior descending occlusion the most sensitive surface lead is V2. Optimal ECG monitoring during PTCA in some cases should involve surface lead V2 or the intracoronary lead.     

U wave inversion during attacks of variant angina.

Sequential 12 lead electrocardiograms were recorded during angina pectoris induced by ergonovine maleate in 38 patients with variant angina. Transient U wave inversion was observed in 17 patients with ST segment elevation in anterior chest leads, but in only three of 21 patients with ST segment elevation in the inferior leads associated with right coronary artery spasm. In the 17, all of whom had spasm of the left anterior descending coronary artery, the sensitivity of ST segment elevation in V5 was only 41%, and that of U wave inversion 71%. U wave inversion without ST segment elevation occurred during attacks in 35% of patients. During the recovery phase, the sensitivity of U wave inversion was 82% in V4 and 65% in V5, though ST segment elevation was absent in both V4 and V5. Thus, inverted U waves without ST segment elevation often appear in marginal ischaemic zones or during the time of recovery from temporary ischaemia. Detection of inverted U waves should aid in the diagnosis of variant angina when only lead V5 is used as a monitor and when electrocardiograms are recorded only during the recovery phase.     

Precordial ST segment elevation in acute ischemia caused by right coronary artery occlusion.

The purpose of this study is to determine why precordial ST elevation (V1 lead) occurs during acute occlusion of the right coronary artery (RCA). Nineteen patients with vasospastic angina, in whom ergonovine administration into RCA provoked spasms, were divided into 2 groups by precordial ST change during spasms. Group I (n = 6) had precordial ST elevation; group II (n = 13) had no precordial ST elevation. A subgroup, IIA was comprised 6 patients in group II with spasms in the RCA proximal segment (segment number less than 2 of AHA coronary classification). None had left coronary dominancy. There was no difference in collateral flow during spasms. Location of spasms in group I was in the RCA proximal segment, and was significantly more proximal compared to group II. There was no difference in sigma ST in II, III, aVF between group I and II or IIA. Max ST elevation time by which duration of ischemia was estimated was significantly longer in group I than in group IIA. Three patients in group I displayed precordial ST depression before elevation, in all of whom in sigma ST in II, III, aVF was higher during precordial ST elevation than during depression. During acute occlusion in the RCA proximal segment, precordial ST elevation is caused by ischemia of the right ventricular anterior wall. Furthermore, precordial ST elevation can occur in a patient with RCA dominance, even if ischemic injury in the left ventricular infero-posterior wall increases progressively.     

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.     

Right coronary artery occlusion: its role in the mechanism of precordial ST segment depression

To investigate the mechanism of precordial ST segment depression during right coronary artery occlusion, precordial ST segment shifts and myocardial lactate metabolism were evaluated during coronary angioplasty in 10 patients with (group A) and 7 patients without (group B) precordial ST segment depression during balloon occlusion of the right coronary artery, and in 17 patients with precordial ST segment depression during balloon occlusion of the left anterior descending artery (group C). A 12 lead electrocardiogram was continuously recorded in each patient. Blood lactate in the aorta and great cardiac vein was measured during the procedure, and the lactate extraction ratio in the anterior wall was determined both before and during balloon occlusion. Eight of the 10 patients in group A and 1 of the 7 patients in group B had a dominant large right coronary artery. There were no significant differences in summed ST segment elevation in leads II, III and a VF between group A (0.56 +/- 0.26 mV) and group B (0.46 +/- 0.19 mV) during balloon occlusion of the right coronary artery, and no significant differences in summed ST segment depression in leads V1 to V6 during balloon occlusion between group A (0.44 +/- 0.26 mV) and group C (0.38 +/- 0.14 mV). Lactate extraction ratio before balloon occlusion was similar among the three groups. Patients in group A had a higher lactate extraction ratio during (38 +/- 11%) compared with before (30 +/- 11%) (p less than 0.05) balloon occlusion despite precordial ST segment depression.(ABSTRACT TRUNCATED AT 250 WORDS)