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

Abstract

To determine whether or not ST segment deviation on admission electrocardiograms can identify patients with anterior acute myocardial infarction due to proximal left anterior descending artery occlusion, the magnitude and location of ST segment elevation or depression were compared between patients with proximal left anterior descending artery occlusion (group A, n = 47) and those with distal left anterior descending artery occlusion (group B, n = 59). ST segment depression in each of the inferior leads was significantly greater in group A than in group B. The incidence of ST segment depression > or = 1 mm in each of the inferior leads (II; 81% vs 27%, III; 85% vs 54%, aVF; 87% vs 47%, P < 0.01) was significantly higher in group A than in group B. In addition, the incidence of ST segment depression > or = 1 mm in all of the inferior leads was significantly greater in group A than in group B (77% vs 22%, P < 0.01). In group A, maximal ST segment elevation was more frequent in lead V2 alone (43% vs 14%, P < 0.01). Group A had greater ST segment elevation in lead aVL than group B, and the incidence of ST segment elevation > or = 1 mm in lead aVL was significantly higher in group A than in group B (66% vs 47%, P < 0.05). ST segment depression > or = 1 mm in all of the inferior leads was most valuable for identifying group A patients (77% sensitivity and 78% specificity). In contrast, the maximal ST segment elevation in lead V2 alone or ST segment elevation > or = 1 mm in lead aVL had a low diagnostic value (43% sensitivity and 86% specificity, 66% sensitivity and 53% specificity, respectively). In conclusion, this study indicates that analysis of ST segment deviation in the inferior leads is useful for identifying patients with acute anterior myocardial infarction due to proximal left anterior descending occlusion.

Differentiation Between Patients With Takotsubo Cardiomyopathy and Those With Anterior Acute Myocardial Infarction

“…[8][9][10][11][12][13][14] In the present study, patients with TC showed a lower frequency of reciprocal ST-segment depression in the inferior leads compared with patients in AMI groups A and B. However, this frequency did not differ between patients with TC and patients in AMI group C, which suggests that reciprocal ST-segment depression in the inferior leads may not be useful for TC from AMI with a culprit lesions in the distal LAD.…”

“…[1][2][3][4][5][6][7] The absence of reciprocal changes, absence of abnormal Q waves, and ∑ST V4-6/∑ST V1-3 >1 have been reported as having high sensitivity and specificity for distinguishing TC from anterior AMI. 3 However, it has been hypothesized that the ECG findings of anterior AMI depend on the site of the culprit lesion and the presence of a wrapped LAD, [8][9][10][11][12][13][14][15] and therefore, we divided the present patients with an anterior AMI into groups according to the site of the culprit lesion and compared their ECG findings with those from patients with TC.…”

Electrocardiographic predictors of proximal left anterior descending coronary artery occlusion

“…Previous studies showed that ST ↓ in inferior leads is a useful marker for identifying proximal LAD artery occlusion during MI [8,13,16,17]. This parameter has also been correlated with the severity of anterior wall ischemia [20][21].…”

“…Most studies have shown a poor correlation between the electrocardiogram (ECG) results and the exact extent of myocardial involvement as determined by autopsy [5,6]. In previous studies, proximal LAD artery lesion before branching S 1 (first septal branch) and/or D 1 (first diagonal branch) could be predicted by the 11 ECG parameters [7][8][9][10][11][12][13][14][15][16][17][18], namely, ST-segment depression (≥1.0 mm) in inferior leads, ST-segment elevation (≥1.0 mm) in lead aVL, ST-segment depression (≥1.0 mm) in lead aVL, ST-segment elevation (≥0.5 mm) in lead aVR, ST-segment elevation (≥2.5 mm) in lead V 1 , ST-segment elevation (<2.5 mm) in lead V 1 , STsegment elevation (≥1.0 mm) in lead V 2 , inverted U wave in lead V 1 to lead V 4 , ST-segment depression (≥1.0 mm) in lead V 5 , T inversion in lead V 4 and/or lead, and a Q wave in lead V 4 to lead V 6 . We decided to asses these ECG findings to predict whether significant lesions in the proximal LAD artery were present in patients with and without signs of anterior myocardial infarction (MI).…”

Angiographic and Clinical Significance of `Transient' ST-Segment Depression in the Lateral Chest Leads in Anterior Wall Acute Myocardial Infarction

“…Patients with ST-segment depression in the inferior leads in anterior wall AMI have been shown to have a higher incidence of proximal LAD occlusion, 15,18,20,21 a larger infarct size, 4,8,12,13,19 and a poorer prognosis. 6,8,12,19 Therefore, the frequency of patients with ST-segment depression in the inferior leads could affect our results.…”