Inferior ST segment depression as a useful marker for identifying proximal left anterior descending artery occlusion during acute anterior myocardial infarction

Influence of the extent of coronary atherosclerotic disease on ST-segment changes induced by ST elevation myocardial infarction

The accuracy of the admission electrocardiogram (ECG) in predicting the site of acute coronary artery occlusion in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease is not well known. This study aimed to assess whether the presence of multivessel coronary artery disease (CAD) modifies the artery-related ST-segment changes in patients with acute coronary artery occlusion. We reviewed the admission ECG, clinical records, and coronary angiography of 289 patients with STEMI caused by acute occlusion of left anterior descending (LAD; n = 140), right (n = 118), or left circumflex (LCx; n = 31) coronary arteries. All patients underwent primary percutaneous coronary reperfusion during the first 12 hours. The magnitude and distribution of artery-related ST-segment patterns were comparable in patients with single (n = 149) and multivessel (n = 140) CAD. Occlusion of proximal (n = 55) or mid-distal (n = 85) LAD artery induced ST-segment elevation in leads V1 to V5, but only the proximal occlusion induced reciprocal ST-segment depression in leads II, III, and aVF (p <0.001). Proximal and mid-distal occlusion of right (n = 45 and 73, respectively) or LCx (n = 15 and 16) coronary artery always induced ST-segment elevation in leads II, III, and aVF and reciprocal ST-segment depression in leads V2 and V3. ST-segment elevation in lead V6 >0.1 mV predicted LCx artery occlusion. In conclusion, patients with STEMI with single or multivessel CAD have concordant artery-related ST-segment patterns on the admission ECG; in both groups, reciprocal ST-segment depression in LAD artery occlusion predicts a large infarct. Subendocardial ischemia at a distance is not a requisite for the genesis of reciprocal ST-segment changes.

Isolated inferior wall ST segment depression as an early sign of acute anterior wall myocardial infarction

BACKGROUND

Reciprocal changes may accompany ST segment elevation in the ischemic territory during acute myocardial infarction (AMI). We examined the hypothesis that isolated inferior ST segment depression on admission is an early sign of anterior wall infarction.

METHODS

49 patients admitted to the coronary care unit between January 1996 and June 2008 who presented with inferior ST segment depression in the absence of ST segment elevation. Electrocardiograms (ECGs) obtained on admission and at 24-48 h were reviewed. Culprit artery was determined based on angiographic and echocardiographic data.

RESULTS

All patients had ST segment depression in the inferior leads on admission. A subgroup (55%) presented with concomitant ST segment depression in V5-V6. Follow-up ECG showed that 35% developed ST segment elevations and/or T wave inversions in anterior wall leads over 24-48 h. The left anterior descending (LAD) artery or one of its branches was the culprit in 60% of the patients. Sum of ST segment depression, V5-V6 involvement or presence of 'hyperacute' T waves did not predict LAD involvement.

CONCLUSION

Isolated ST segment depression in the inferior wall leads during ACS is usually an early sign of anterior wall AMI, in which the LAD or one of its branches is the culprit artery.

Diagnostic Value of Electrocardiographic T Wave Inversion in Lead aVL in Diagnosing Coronary Artery Disease in Patients with Chronic Stable Angina

OBJECTIVES

The clinical value of T wave inversion in lead aVL in diagnosing coronary artery disease (CAD) remains unclear. This study aims to investigate the correlation between aVL T wave inversion and CAD in patients with chronic stable angina.

METHODS

Electrocardiograms (ECGs) of 257 consecutive patients undergoing coronary angiography were analyzed. All patients had chronic stable angina. All patients with secondary T wave inversion had been excluded (66 patients). The remaining 191 patients constituted the study population. Detailed ECG interpretation and coronary angiographic findings were conducted by experienced cardiologists.

RESULTS

T wave inversion in aVL was identified in 89 ECGs (46.8%) with definite ischemic Q-ST-T changes in different leads in 97 ECGs (50.8%). Stand alone aVL T wave inversion was found in 27 ECGs (14.1%) while ischemic changes in other leads with normal aVL were identified in 36 ECGs (18.8%). The incidence of CAD was 86.3%. Single, two- and multi-vessel CAD were found in 38.8%, 28.5% and 32.7% of cases respectively. The prevalence of left main, left anterior descending, left circumflex and right coronary arteries were 4.7%, 61.2%, 29.3% and 44.5%, respectively. T wave inversion in aVL was found to be the only ECG variable significantly predicting mid segment left anterior descending artery (LAD) lesions (Odds Ratio 2.93, 95% Confidence Interval 1.59-5.37, p=0.001).

CONCLUSION

This study provides new information relating to T wave inversion in lead aVL to mid segment LAD lesions. Implication of this simple finding may help in bedside diagnosis of CAD typically mid LAD lesions. However, further studies are needed to corroborate this finding.

A new electrocardiographic algorithm to locate the occlusion in left anterior descending coronary artery

BACKGROUND

Early prediction of proximal left anterior descending coronary artery (LAD) occlusion is essential from a clinical point of view

HYPOTHESIS

To develop an electrocardiogram (ECG) algorithm based on ST-segment deviations to predict the location of occlusion of LAD as a culprit artery.

METHODS

ECG and angiographic findings were correlated in 100 patients with an ST-segment elevation myocardial infarction (MI) in precordial leads V(1), V(2), and V(4) through V(6).

RESULTS

ST-depression > or = 2.5 mm in leads III + ventricular fibrillation (VF) presents sensitivity (SE) of 77% and specificity (SP) of 84% for LAD occlusion proximal to the first diagonal artery (D1). ST-segment in III + VF isoelectric or elevated, presents SE of 44% and SP of 100% for LAD occlusion distal to D1. Subsequent analysis of the equation summation operator of ST-deviation in VR + V(1) - V(6) < 0, allows us to predict occlusion distal to first septal artery (S1) with 100% SP. On the other hand, any ST-depression in III + VF > 0.5 mm + summation operator of ST-deviation in VR + V(1) - V(6) > or = 0 identifies a high-risk group (lower ejection fraction, worse Killip findings, higher peak of CPK and CK-MB, and major adverse cardiac events [MACE]: death, reinfarction, recurrent angina, persistent left ventricular failure, or sustained ventricular arrhythmia during hospitalization).

CONCLUSIONS

This sequential ECG algorithm based on ST-segment deviations in different leads allowed us to predict the location of occlusion in LAD with good accuracy. Cases with proximal LAD occlusion present the most markers of poor prognosis. We recommend the use of the algorithm in everyday clinical practice.

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.

Value of T-wave direction with lead III ST-segment depression in acute anterior wall myocardial infarction: electrocardiographic prediction of a "wrapped" left anterior descending artery

BACKGROUND

Lead III ST-segment depression during acute anterior wall myocardial infarction (AMI) has been attributed to reciprocal changes. However, the value of the T-wave direction (positive or negative) in predicting the site of obstruction and type of the left anterior descending (LAD) artery is not clear and has not been studied before.

HYPOTHESIS

The aim of the study was to assess retrospectively the correlation between two patterns of lead III ST-segment depression, and type of LAD artery and its level of obstruction during first AMI.

METHODS

The study group consisted of 48 consecutive patients, admitted to the coronary care unit for first AMI, who showed ST-segment elevation in lead a VL and ST-segment depression in lead III on admission 12-lead electrocardiogram. The patients were divided by T-wave direction into Group 1 (n = 31), negative T wave, and Group 2 (n = 17), positive T wave. The coronary angiogram was evaluated for type of LAD ("wrapped", i.e., surrounding the apex or not), site of obstruction (pre- or postdiagonal branch), and other significant coronary artery obstructions.

RESULTS

Mean lead III ST-segment depression was 1.99 +/- 1.32 mm in Group 1 and 1.13 +/- 0.74 mm in Group 2 (p = 0.004); mean ST-segment elevation in a VL was 1.35 +/- 0.84 mm and 1.23 +/- 0.5 mm, respectively (p = 0.5). A wrapped LAD was found in 12 patients (38.7%) in Group 1 and in 13 in Group 2 (76.4%) (p = 0.02). The sensitivity of lead III ST-segment depression with positive T wave to predict a wrapped LAD was 52%, and the specificity was 82% with a positive predictive value of 76%. On angiography, 25 patients (80%) in Group 1 and 13 (76%) in Group 2 had prediagonal occlusion of the LAD (p = 0.77). No significant difference between groups was found for right and circumflex coronary artery involvement or incidence of multivessel disease.

CONCLUSIONS

The presence of lead III ST-segment depression with positive T wave associated with ST-segment elevation in a VL in the early course of AMI can serve as an early electrocardiographic marker of prediagonal occlusion of a "wrapped" LAD.

Electrocardiographic predictors of proximal left anterior descending coronary artery occlusion

Proximal occlusion of the left anterior descending coronary artery (LAD) results in a less favorable prognosis in coronary angiography. Therefore, it is important to determine whether there are significant lesions in LAD by electrocardiography (ECG) before coronary angiography. Twelve-lead ECG was compared in 130 patients with significant lesions (≥70% stenosis) confined to proximal part of the LAD (P LAD group) and 492 patients with normal coronary angiography (control group). Fifty-nine patients in the P LAD group and 18 patients in the control group had signs of anterior myocardial infarction as shown by ST elevation (≥1.0 mV) in two consecutive pericardial leads or the presence of a pathological Q wave. An inverted U wave (biphasic T wave) in leads V1 to V4 had a sensitivity of 49.3% (35/71) in P LAD patients without signs of anterior myocardial infarction (MI) and 96.6 % (57/59; specificity, 66.6%; positive predictive value, 90.9 %) in the P LAD patients with signs of anterior MI. In the P LAD patients with signs of anterior MI, T inversion in V4–V5 had a lower sensitivity (67.0% [40/59]) than an inverted U wave. ST depression in inferior leads and ST depression in V5 were not useful markers of proximal LAD occlusion. In conclusions, an inverted U wave in V1 to V4 (or in each of these leads) and T inversion in V4–V5 are the best predictors of significant proximal LAD lesion, especially in patients with ECG findings of anterior MI.

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.

Acute coronary syndromes

Despite technologic advances in many diagnostic fields, the 12-lead ECG remains the basis for early identification and management of an acute coronary syndrome. This article reviews the use of the ECG in acute coronary syndromes.

Differentiation between patients with takotsubo cardiomyopathy and those with anterior acute myocardial infarction

BACKGROUND

There has not been a comparison of the electrocardiographic (ECG) finding of ST-segment elevation in the precordial leads in patients with takotsubo cardiomyopathy (TC) and those with anterior acute myocardial infarction (AMI), with regard to the location of the culprit lesion.

METHODS AND RESULTS

The present study evaluated 18 patients with TC, and 85 with anterior AMI who were divided into 3 groups: group A had the culprit lesion proximal to both the first septal branch (S1) and the first diagonal branch (D1), group B had the culprit lesion proximal to either S1 or D1, and group C had the culprit lesion distal to both S1 and D1. In patients with TC, reciprocal ST-segment depression in the inferior leads was observed less frequently than in patients in groups A (p<0.0001) and B (p=0.0002), and abnormal Q waves and ST-segment elevation in the inferior leads were observed more frequently than in group A (p=0.0007, p=0.0057, respectively). The ECG findings in TC did not differ from those in group C.

CONCLUSION

Electrocardiographic findings may differentiate TC from AMI with a proximal lesion of left anterior descending coronary artery, but not those with distal lesions.

Clinical and angiographic characteristics of patients with combined anterior and inferior ST-segment elevation on the initial electrocardiogram during acute myocardial infarction

OBJECTIVE

We evaluated the significance of combined anterior and inferior ST-segment elevation on the initial electrocardiogram (EKG) in patients with acute myocardial infarction (AMI) and correlated it with AMI size and left ventricular (LV) function.

METHODS

We analyzed admission EKGs of 2996 patients with AMI from the GUSTO-I angiographic substudy and the GUSTO-IIb angioplasty substudy who underwent immediate angiography. In all, we identified 1046 patients with anterior ST elevation (ST-segment elevation in > or =2 of leads V1-V4) and divided them into 3 groups: Group 1, anterior + inferior ST elevation (ST elevation in > or =2 of leads II, III, aVF, n =179); Group 2, anterior ST elevation only (<2 of leads II, III, aVF with ST elevation or depression, n = 447); Group 3, anterior ST elevation + superior ST elevation (ST depression in > or =2 of leads II, III, aVF, n = 420).

RESULTS

Cardiac risk factors, prior AMI, prior percutaneous transluminal coronary angioplasty or coronary artery bypass graft, Killip class, and thrombolytic therapy assignment did not differ among the 3 groups. Group 1 patients had greater number of leads with ST elevation compared to Groups 2 and 3 (ST elevation in > or =6 leads 83% vs 22% vs 49%, P =.001). Despite greater ST-segment elevation, Group 1 patients had a lower peak CK level (median baseline peak CK 1370 vs 1670 vs 2381 IU, P =.0001) and less LV dysfunction (median ejection fraction 0.53 vs 0.49 vs 0.45, P =.0001; median number of abnormal chords 21 vs 32 vs 40, P =.0001). Angiographically, Group 1 had 2 distinct subsets of patients with either right coronary artery (RCA) (59%) or left anterior descending coronary artery (LAD) (36%) occlusion. In contrast, the infarct-related artery (IRA) was almost entirely the LAD in Groups 2 and 3 (97%). Further, the site of IRA occlusion in Group 1 was mostly proximal RCA (67%) in the RCA subgroup and mid or distal LAD (70%) in the LAD subgroup. ST-segment elevation in lead V1 > or = V3 and absence of progression of ST elevation from lead V1 to V3 on the EKG differentiated IRA-RCA from IRA-LAD in patients with combined anterior and inferior ST elevation.

CONCLUSIONS

The AMI size and LV dysfunction in patients with anterior ST elevation is directly related to the direction of ST segment deviation in the leads II, III, aVF; least with inferior ST elevation, intermediate with no ST deviation, and maximal with superior ST elevation (inferior ST depression). Despite greater ST-segment elevation, patients with combined anterior and inferior ST elevation have limited AMI size and preserved LV function. Angiographically, they comprise 2 distinct subsets with either proximal RCA or mid to distal LAD occlusion. A predominant right ventricular and limited inferior LV AMI from a proximal RCA occlusion, or a smaller anterior AMI from a more distal occlusion of LAD may explain their limited AMI size despite greater ST elevation.

[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.

[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.

Electrocardiographic diagnosis of acute myocardial infarction: Current concepts for the clinician

BACKGROUND

Over the past 2 decades, the 12-lead electrocardiogram has attained special significance for the diagnosis and triage of patients with chest pain because timely detection of myocardial injury and a rapid assessment of myocardium at risk proved pivotal to implementing effective reperfusion therapies during acute myocardial infarction. However, this wealth of information could still be underutilized by clinicians who may restrict their diagnostic quest in patients with chest pain to the more classic electrocardiographic signs.

METHODS

The medical literature on electrocardiographic manifestations of acute myocardial infarction was extensively reviewed.

RESULTS

The widespread utilization of both coronary angiography and methods to determine myocardial function and metabolism in patients with acute myocardial infarction over the last 10 years has provided the means for rigorous comparisons with electrocardiographic information. We summarize these electrocardiographic signs and patterns in terms of their relevance to the clinician to help reduce the incidence of "nondiagnostic electrocardiograms" and improve timely decision-making.

CONCLUSIONS

The electrocardiogram continues to be an invaluable tool in the initial evaluation of patients with chest pain. The plethora of data currently available on electrocardiographic changes correlating with myocardial injury allows clinicians to make faster and better decisions than ever before.

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.

Angiographic and clinical significance of 'transient' ST-segment depression in the lateral chest leads in anterior wall acute myocardial infarction

This study aimed to clarify the significance of ST-segment depression in the lateral chest leads in anterior wall acute myocardial infarction (AMI) with ST-segment elevation. A total of 196 patients with their first anterior wall AMI (< or =6h) were divided into 2 groups according to the presence (group A, n=39) or absence (group B, n=157) of ST-segment depression > or =0.1 mV in V5 and/or V6 on the admission electrocardiogram. Patients with electrocardiographic confounding factors were excluded. No patients had persistent ST-segment depression in the lateral chest leads. Emergency coronary angiography revealed that group A had higher incidences of occlusion of the left anterior descending coronary artery (LAD) proximal to its first septal branch (77% vs 51%, p<0.01) and good collateral circulation than group B (46% vs 25%, p<0.05). Peak creatine kinase levels were significantly lower in group A than in group B (2060+/-1099 vs 2873+/-2077 IU/L, p<0.01). Left ventricular ejection fraction in the chronic phase was significantly greater in group A than in group B. Regional wall motion in the infarct region in the chronic phase was better in group A than in group B. These results indicate that patients with 'transient' ST-segment depression in the lateral chest leads in anterior wall AMI had a relatively smaller infarct size, despite their higher incidence of occlusion of the LAD proximal to its first septal branch, because of their higher incidence of good collateral circulation.

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.