Clinical utility of ST-segment depression in lead AVR in acute myocardial infarction

The present study evaluated the prevalence and significance of ST-segment depression (STD) in lead aVR on the admission 12-lead electrocardiogram in 307 consecutive patients with an acute myocardial infarction (AMI) with ST-segment elevation. STD in aVR was present in a significantly higher proportion of patients with inferior/posterior AMIs. Within inferior/posterior AMIs those with STD in aVR had significantly more concomitant STD in V(1), V(2), V(3) and more concomitant STesegment elevation in V(5), V(6) and right precordial leads. These data suggests that STD in aVR may point to a coronary artery with a large area of supply as the culprit vessel responsible for the AMI.     

Identification of the optimal electrocardiographic leads for detecting acute epicardial injury in acute myocardial infarction

Current coronary care electrocardiographic (ECG) monitoring techniques are aimed at detection of cardiac arrhythmias rather than myocardial ischemia. However, in patients with acute myocardial infarction (AMI) who undergo reperfusion therapy, monitoring ST-segment deviation could provide an early noninvasive indicator of coronary artery reocclusion. In this study, the admission 12-lead ECGs of patients with initial AMI were used to propose optimal lead locations for ST-segment monitoring. The study population was selected from consecutive Duke University Medical Center admissions during 1965 to 1981 who met the following inclusion criteria: chest pain for no more than 8 hours, initial AMI documented by ECG and 3 of 4 enzyme criteria, greater than or equal to 0.1 mV (1 mV = 10 mm) of ST elevation in at least 1 of the standard 12 leads (not aVR) on admission ECG, and no ECG evidence of conduction disturbances, ventricular hypertrophy or tachycardia. ST-segment deviation was quantified; AMI location was assigned based on the lead with maximal deviation. Of the 80 patients who had an inferior AMI, lead III was both the most frequent location for ST elevation (94%) and the most common site with maximal ST deviation. Lead V2 had the highest incidence of ST-segment depression (60%). In the 68 patients who had an anterior AMI, lead V2 had the highest frequency of ST elevation (99%). Leads V2 and V3 were the most common sites of maximal elevation. Thus, for monitoring ST deviation, leads III and V2 may be superior to leads II and V1, which are commonly used in arrhythmia monitoring.(ABSTRACT TRUNCATED AT 250 WORDS)     

ST-segment depression in lead aVR predicts predischarge left ventricular dysfunction in patients with reperfused anterior acute myocardial infarction with anterolateral ST-segment elevation.

BACKGROUND: Patients with an anterolateral acute myocardial infarction (AMI) have a worse prognosis, and those with additional inferolateral wall involvement might be higher risk because of more extensive area at risk. Lead -aVR obtained by inversion of images in lead aVR has been reported to provide useful information for inferolateral lesion. METHODS: We examined the relation between ST-segment deviation in lead aVR on admission electrocardiogram (ECG) and left ventricular function in 105 patients with an anterolateral AMI undergoing successful reperfusion < or = 6 hours after onset. Patients were classified according to ST-segment deviation in lead aVR on admission ECG: group A, 23 patients with ST elevation of > or = 0.5 mm; group B, 47 patients without ST deviation; and group C, 35 patients with ST depression of > or = 0.5 mm. RESULTS: There were no differences among the 3 groups in age, sex, or site of the culprit lesion. In groups A, B, and C, the peak creatine kinase level was 3661 +/- 1428, 4440 +/- 1889, and 6959 +/- 2712 mU/mL, and the left ventricular ejection fraction (LVEF) measured by predischarge left ventriculography was 54% +/- 9%, 48% +/- 7%, and 37% +/- 9%, respectively(P < .01). During hospitalization, congestive heart failure occurred more frequently in group C than in groups A or B (P < .05). ST-segment depression in lead aVR had a higher predictive accuracy than other ECG findings in identifying patients with predischarge LVEF < or = 35%. CONCLUSIONS: We conclude that in patients with an anterolateral AMI, ST-segment depression in lead aVR on admission ECG is useful for predicting larger infarct and left ventricular dysfunction despite successful reperfusion.     

ECG discrimination between right and left circumflex coronary arterial occlusion in patients with acute inferior myocardial infarction: value of old criteria and use of lead aVR

STUDY OBJECTIVES: Prior studies have proposed several ECG criteria for identifying the culprit artery in patients with acute inferior myocardial infarction (MI). We applied each criterion to our patients to assess its utility. In doing so, we discovered a previously unreported, but highly useful, criterion utilizing lead aVR. STUDY DESIGN: Retrospective review. PATIENTS: Thirty consecutive patients with symptoms of acute MI, ST-segment elevation in the inferior ECG leads, an appropriate rise and fall of creatine kinase and troponin I levels, and coronary arteriography within 7 days of the onset of symptoms. MEASUREMENTS: The ECG recorded within 24 h of the onset of symptoms that had the most prominent ST-segment changes was analyzed. In the 12 standard leads and in lead V(4)R, ST-segment elevation or depression was measured 0.06 s after the J point. RESULTS: Four previously described criteria were useful in identifying the right coronary artery (RCA) or the left circumflex coronary artery (LCX) as the culprit: ST-segment elevation in lead I, ST-segment more or less elevated in lead II than in lead III, ST-segment elevation >or= 0.5 mm in lead V(4)R, and various combinations of ST-segment elevation or depression in leads V(1) and V(2). A new criterion was found to be at least as useful as any previously described: the presence and amount of ST-segment depression in lead aVR. CONCLUSIONS: At least five different ST-segment criteria help to identify the RCA or the LCX as the culprit artery in patients with acute inferior MI. One of these, the amount of ST-segment depression in lead aVR, has not been reported previously and needs validation in a larger study.     

Electrocardiographic identification of the infarct-related artery in acute inferior myocardial infarction.

INTRODUCTION: Mortality and morbidity from acute inferior myocardial infarction (MI) are determined, among other factors, by the infarct-related artery (IRA). Several electrocardiographic (ECG) criteria have been proposed to differentiate between the right coronary artery (RCA) and the left circumflex coronary artery (LCx) as the IRA in inferior MI. Recently, a new criterion has been proposed (ST segment depression in lead aVR). It was our objective to evaluate the old and the new ECG criteria in identifying the IRA in patients with inferior MI. METHODS: Patients with inferior MI treated by primary angioplasty were included, following evaluation of the admission ECG. Patients with a previous history of Q-wave myocardial infarction and complete bundle branch block were excluded. The artery with the most severe lesion was considered the IRA. The following ECG criteria were assessed: ST depression in lead DI; ST depression in leads V1 and V2, ST elevation in lead DIII > DII, ST depression in V3/ST elevation in DIII ratio > 1.2 (classical criteria) and ST depression in lead aVR. ST-segment elevation or depression was measured 0.06 sec after the J point. RESULTS: 53 patients were included (mean age 59.1 +/- 13.9 years, 38 males). The RCA was the IRA in 38 patients and the LCx in 15. Baseline characteristics (age, gender, TIMI flow, Killip class, and pain-to-balloon time) were similar in both groups. All the classical criteria were able to identify the IRA. The new criterion--ST depression in lead aVR--identified the IRA in a small number of patients (sensitivity 33%, specificity 71%, p = NS). CONCLUSIONS: The 4 classical criteria were useful in identifying the IRA in patients with inferior MI. ST depression in lead aVR (a recently proposed new criterion), on the other hand, showed limited utility in differentiating between RCA and LCx.     

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.     

心电图改变对急性下壁心肌梗死相关血管的预测价值

目的:对急性下壁心肌梗死患者的心电图资料进行回顾性研究,分析和比较心电图改变与冠状动脉造影及临床特点的对应性关系。探讨体表心电图改变对急性下壁心肌梗死患者的临床价值。方法:选取86例急性下壁心肌梗死患者,根据冠状动脉造影结果分为右冠状动脉(RCA)病变组和左冠状动脉(LCA)病变组。对比分析其心电图改变与冠状动脉造影结果及临床特点。结果:Ⅰ、Ⅱ、Ⅲ、aVR导联ST段及aVL导联波形改变对诊断梗死相关血管具有重要价值;V3与Ⅲ导联ST段改变比值预测梗死相关血管部位具有重要价值;伴aVR导联ST段压低患者病情重;伴胸前导联ST段压低者病情重、并发症发生率明显增高。结论:心电图对诊断下壁急性心肌梗死相关血管及其临床特点具有重要的预测价值。     

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.     

ST-segment deviation in lead aVR on admission is not associated with left ventricular function at predischarge in first anterior wall ST-segment elevation acute myocardial infarction

Previous studies have shown that the analysis of ST-segment deviation in lead aVR on admission provides useful information on angiographic coronary anatomy and risk stratification in acute coronary syndromes. However, the association between ST-segment deviation in lead aVR on admission and left ventricular (LV) function has not been fully investigated in anterior wall acute ST-segment elevation myocardial infarction. In this study, 237 patients with first anterior wall acute ST-segment elevation myocardial infarction were examined. The patients were divided into the following 3 groups according to ST-segment deviation in lead aVR on admission: 85 with ST-segment elevation ≥0.5 mm (group A), 106 without ST-segment deviation (group B), and 46 with ST-segment depression ≥0.5 mm (group C). LV ejection fractions at predischarge were compared among the 3 groups. Among the 3 groups, there were significant differences in the prevalences of proximal left anterior descending coronary artery (LAD) occlusion (group A 75.3%, group B 56.6%, group C 45.7%, p = 0.002), long LAD (group A 27.1%, group B 31.1%, group C 56.5%, p = 0.002), and good collaterals to the LAD (group A 40.0%, group B 25.4%, group C 17.4%, p = 0.01). LV ejection fractions at predischarge did not differ among the 3 groups (group A 56.4 ± 12.5%, group B 56.9 ± 12.7%, group C 53.3 ± 12.2%, p = 0.26). On a multiple regression analysis, establishment of Thrombolysis In Myocardial Infarction grade 3 flow, proximal LAD occlusion, and long LAD were associated with the LV ejection fraction at predischarge. In conclusion, ST-segment deviation in lead aVR on admission is not associated with LV function at predischarge in first anterior wall acute ST-segment elevation myocardial infarction.     

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.     

Clinical characteristics of ST-segment elevation in lead V6 in patients with Q-wave acute inferior wall myocardial infarction

BACKGROUND: Precordial ST-segment depression in acute inferior infarction is well recognized, but few studies have evaluated ST-segment elevation in lateral precordial leads. The present study examined the clinical significance of ST-segment elevation in lead V6 in patients with acute Q-wave inferior myocardial infarction. METHODS: We studied the initial electrocardiography of 125 consecutive patients with acute Q-wave inferior myocardial infarction admitted to hospital within 12 h of the onset of chest pain. They were classified into two groups: group 1 = 34 patients with ST-segment elevation in lead V6; group 2 = 91 patients with no ST-segment elevation in lead V6. RESULTS: Among the seven clinical variables examined, the number of left ventricular asynergic segments (P < 0.001) and pulmonary capillary wedge pressure (P = 0.001) were related to ST-segment elevation in lead V6. The incidences of major arrhythmias (50% compared with 31%, P = 0.04), pericardial effusion (32% compared with 9%, P = 0.003), and pericardial rub (15% compared with 2%, P = 0.02) during the patients' stay in hospital were greater in group 1 than in group 2. Among the patients in group 1, the right coronary artery was the culprit artery in 22 of 24 patients (92%) with ST segment depression in lead I, whereas the circumflex artery was the culprit artery in nine of 10 patients (90%) with isoelectric or ST-segment elevation in lead I. CONCLUSION: The presence of ST-segment elevation in lead V6 in patients with acute Q-wave inferior myocardial infarction was associated with larger infarct size, and greater incidences of major arrhythmias and pericardial involvement during the patient's stay in hospital.     

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   

ST-segment elevation resolution in lead aVR: a strong predictor of adverse outcomes in patients with non-ST-segment elevation acute coronary syndrome.

BACKGROUND: The impact of ST-segment elevation resolution in lead aVR on outcomes in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) is unclear. METHODS AND RESULTS: Electrocardigrams (ECGs) were recorded on admission and 6 h later in 367 patients with NSTE-ACS. ST-segment deviation >or=0.5 mm was considered significant: 92 patients had ST-segment elevation in lead aVR on admission ECG (ST upward arrowaVR), and 275 did not. Among patients with ST upward arrowaVR, 50 had ST resolution, defined as a reduction >50% in the degree of ST-segment elevation in lead aVR from admission to 6 h later, and 42 did not. ST upward arrowaVR without ST resolution was associated with older age, greater ST-segment depression in other leads on admission and 6 h later, higher rates of positive troponin T, left main and/or 3-vessel coronary disease, and adverse events such as death, (re)infarction, or urgent revascularization within 30 days after admission. Multivariate analysis showed that ST upward arrowaVR without ST resolution was the strongest independent predictor of death or (re)infarction within 30 days after admission (hazard ratio 5.62, p=0.018). CONCLUSIONS: ST upward arrowaVR without ST resolution is a strong predictor of 30-day adverse outcomes and correlates with the extent and severity of coronary artery disease in patients with NSTE-ACS.     

Significance of lead aVR in acute coronary syndrome

The 12-lead electrocardiogram(ECG)is a crucial tool in the diagnosis and risk stratification of acute coronary syndrome(ACS).Unlike other 11 leads,lead aVR has been long neglected until recent years.However,recent investigations have shown that an analysis of ST-segment shift in lead aVR provides useful information on the coronary angiographic anatomy and risk stratification in ACS.ST-segment elevation in lead aVR can be caused by(1)transmural ischemia in the basal part of the interventricular septum caused by impaired coronary blood flow of the first major branch originating from the left anterior descending coronary artery;(2)transmural ischemia in the right ventricular outflow tract caused by impaired coronary blood flow of the large conal branch originating from the right coronary artery;and(3)reciprocal changes opposite to ischemic or non-ischemic ST-segment depression in the lateral limb and precordial leads.On the other hand,ST-segment depression in lead aVR can be caused by transmural ischemia in the inferolateral and apical regions.It has been recently shown that an analysis of T wave in lead aVR also provides useful prognostic information in the general population and patients with prior myocardial infarction.Cardiologists should pay more attention to the tracing of lead aVR when interpreting the12-lead ECG in clinical practice.     

Consideration of the total ST-segment deviation on the initial electrocardiogram for predicting final acute posterior myocardial infarct size in patients with maximum ST-segment deviation as depression in leads V1 through V3. A FRISC II substudy

BACKGROUND: Because patients with acute left circumflex occlusion are typically characterized primarily on the standard 12-lead electrocardiogram (ECG) by ST depression, they do not qualify to receive reperfusion therapy. Documentation of a relationship between the quantities of acute ST change and final QRS estimated acute myocardial infarction (AMI) size could form the basis for clinical trials to determine the value of reperfusion therapy. METHOD: The Fragmin and Fast Revascularization during Instability in Coronary artery disease trial included 3214 patients with unstable coronary artery disease. Two percent of the patients (n = 69) had maximum ST-segment depression in leads V 1 through V 3 and were selected for this study. Initial ECG changes were compared to final myocardial infarction size, using the Selvester QRS score as the end point. RESULTS: The quantity of initial ST-segment deviation correlated with the final AMI size (r = 0.43, P < .0005). The formula 3[0.22 (SigmaST downward arrow + SigmaST upward arrow) -0.02], where downward arrow indicates depression and upward arrow elevation, derived from measurements on the initial ECG, predicted the size of the AMI in percentage of the left ventricle as estimated on the final ECG. The study population had a large proportion of AMI (73%) indicated to be in or adjacent to the posterior left ventricular wall. CONCLUSION: The quantitative initial ST-segment deviation correlates linearly to the final AMI size in patients with maximum ST-segment depression in leads V 1 through V 3. The formula derived could be valuable for selecting patients who fail to meet strict ST-elevation AMI criteria for emergency intravenous or intracoronary reperfusion therapy.     

A case of painless myocardial injury probably caused by coronary artery spasm]

A 53-year-old male was admitted to the hospital due to electrocardiographic ST-segment elevation in V1-4 with ST-segment depression in the inferior leads, which suggested acute myocardial infarction. He had a cough and a slight fever without chest pain. Serum creatine kinase and its myocardial band were slightly elevated but creatine kinase value did not exceed twice the normal upper limit. Emergent coronary arteriography (CAG) revealed intact coronary arteries. The CAG in a chronic stage again revealed intact coronary arteries. Intracoronary administration of acetylcholine of 100 micrograms to the left coronary artery and 50 micrograms to the right coronary artery provoked diffuse spasm in the right and left coronary arteries. The electrocardiogram (ECG) during the right coronary artery spasm revealed ST-segment depression in the inferior leads with ST-segment elevation in V2 and V3, which resembled the ECG finding at the time of the patient's admission. With intracoronary isosorbide dinitrate, the spasm and ST-segment elevation were resolved. These findings strongly suggest that coronary spasm can cause myocardial injury indicated by a slight elevation of serum creatine kinase value.     

Implications of ST-segment elevation in leads V5 and V6 in patients with reperfused inferior wall acute myocardial infarction

During inferior acute myocardial infarction, ST-segment elevation (ST↑) often occurs in leads V(5) to V(6), but its clinical implications remain unclear. We examined the admission electrocardiograms from 357 patients with a first inferior acute myocardial infarction who had Thrombolysis In Myocardial Infarction 3 flow of the right coronary artery or left circumflex artery within 6 hours after symptom onset. The patients were divided according to the presence (n = 76) or absence (n = 281) of ST↑ >2 mm in leads V(5) and V(6). Patients with ST↑ in leads V(5) and V(6) were subdivided into 2 groups according to the degree of ST↑ in leads III and V(6): ST↑ in lead III greater than in V(6) (n = 53) and ST↑ in lead III equal to or less than in V(6) (n = 23). The perfusion territory of the culprit artery was assessed using the angiographic distribution score, and a mega-artery was defined as a score of ≥0.7. ST↑ in leads V(5) and V(6) with ST↑ in lead III greater than in V(6) and ST↑ in leads V(5) and V(6) with ST↑ in lead III equal to or less than in V(6) were associated with mega-artery occlusion and impaired myocardial reperfusion, as defined by myocardial blush grade 0 to 1. Right coronary artery occlusion was most common (96%) in the former, and left circumflex artery occlusion was most common (96%) in the latter, especially proximal left circumflex occlusion (74%). Multivariate analysis showed that ST↑ in leads V(5) and V(6) with ST↑ in lead III greater than that in V(6) (odds ratio 4.81, p <0.001) and ST↑ in leads V(5) and V(6) with ST↑ in lead III equal or less than that in V(6) (odds ratio 5.96, p <0.001) were independent predictors of impaired myocardial reperfusion. In conclusion, ST↑ in leads V(5) and V(6) suggests a greater risk area and impaired myocardial reperfusion in patients with inferior acute myocardial infarction. Furthermore, comparing the degree of ST↑ in lead V(6) with that in lead III is useful for predicting the culprit artery.     

The relationship between initial ST-segment deviation and final QRS complex changes related to the posterolateral wall in acute inferior myocardial infarction

Objectives

The aim of this study was to assess the relationship between initial ST-segment deviation and final QRS complex changes related to the posterolateral left ventricular wall in patients with acute inferior myocardial infarction receiving reperfusion therapy. The secondary aim was to determine if this relationship is stronger for patients who present early in the ischemia/infarction process in comparison with patients who present late.

Methods

The ST-segment depression in the leads V₁, V2, and −V6 were measured in the electrocardiograph (ECG) just before initiation of myocardial reperfusion. These leads were chosen because they represent the posterolateral wall in the Selvester score. In addition, the Anderson-Wilkins acuteness score was calculated in the admission ECG. Selvester criteria related to the posterolateral wall were identified in the ECG performed before hospital discharge to assess final infarct size.

Results

Fifty-six patients were included in this study. No significant relationship was found between the sum of initial ST-segment depression in the leads V₁, V₂, and −V₆, and final infarct size in the posterolateral left ventricular wall for the total study population (r = 0.19, P = .16). Patients were subgrouped by Anderson-Wilkins acuteness score of less than 3 vs 3 or more. In those with a low acuteness score, the amount of ST-segment depression had no relationship with final infarct size (r = −0.16, P = .41). However, the correlation was statistically significant for those with a high acuteness score (r = 0.42, P = .04).

Conclusion

The initial ST-segment depression in leads V₁, V₂, and −V₆ can predict ECG-estimated amount of infarction in the posterolateral left ventricular wall in patients with acute inferior myocardial infarction receiving reperfusion therapy, but only in those who present early in the ischemia/infarction process.     

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。     

aVR 导联对急性心肌梗死中左主干病变的诊断意义

目的：通过分析急性心肌梗死患者12导联心电图,探讨心电图对左主干病变的诊断意义。方法对急性心肌梗死并行冠脉造影术的4914例患者进行分层随机抽样,根据造影结果,将样本分为左主干病变组及非左主干病变组。记录两组一般临床资料,盲法测量两组心电图,对比两组得出预测左主干病变的指标。结果二元 logistic 回归分析表明,aVR 导联 ST 段抬高≥0．05 mV（OR：8．160,P ＜0．05）是左主干病变的独立预测因子。联合 aVR 导联ST 段抬高≥0．05 mV、V4～V6导联 ST 段压低、≥5个导联 ST 段压低、aVF 导联低电压、QRS 波群时限＞100 ms 这5个无创性指标,可将确诊左主干病变的概率从25．19％提高到69．24％。5个心电图指标的阳性预测值分别为52．63％、32．73％、26．39％、16．22％和22．22％。结论心电图对急性心肌梗死中左主干病变的预测是可行的。aVR 导联 ST 段抬高≥0．05 mV 是预测左主干病变良好的心电图指标,联合多指标可提高心电图对左主干病变的诊断价值。