High-risk electrocardiogram presentations in the acute coronary syndrome patient – Beyond ST-segment elevation myocardial infarction

Figure 1. Acute posterior wall myocardial infarction (APMI). Recall that the posterior wall of the left ventricular is indirectly imagined by the 12-lead electrocardiogram, using leads V1 to V4. When viewing the posterior wall from this perspective, the abnormalities consistent with APMI are reversed. (a) Large R-wave, flat (horizontal) ST segment depression, and upright T-wave, findings very suggestive of APMI. (b) Leads V1 to V3, indirectly imaging the posterior wall of the left ventricle with Large R-wave, flat (horizontal) ST segment depression, and upright T-wave. (c) Leads V1 to V3, indirectly imaging the posterior wall of the left ventricle with Large R-wave, flat (horizontal) ST-segment depression, and upright T-wave– when all three findings are present, the likelihood of APMI is extremely high

Figure 2. (a-c) Hyperacute T-wave of early STEMI. Note the prominent T-wave with a broad base, asymmetric morphology, and J-point elevation

Figure 3. De Winter syndrome. (a) Lead V3 with prominent, hyperacute T-wave and J-point depression with accompanying T-segment depression. (b) Leads V1 to V4 with prominent, hyperacute T-wave and J-point depression with accompanying T-segment depression; similar ST-segment depression is also noted in leads V5 and V6

Figure 4. First diagonal branch of left anterior descending artery acute occlusion. (a) ST-segment elevation in leads aVL and V2 along with ST-segment depression in the inferior leads. (b) Annotated electrocardiogram from “A” with ST-segment elevation in leads aVL and V2 (small arrows) along with ST-segment depression in the inferior leads (large arrows)

Figure 5. LBBB with anticipated and abnormal ST-Segment-T-wave Configurations. (a) Concept of Appropriate Discordance– note that the terminal portion of the QRS complex and ST-segment are located on opposite sides of the isoelectric baseline; this relationship is the anticipated electrocardiogram (ECG) appearance of an uncomplicated LBBB. (b) Modified Sgarbossa Criteria for AMI diagnosis in LBBB– 3 ECG findings which are strongly suggestive of AMI in the setting of LBBB and appropriate clinical presentation, including concordant ST-segment elevation, concordant ST-segment depression, and excessive (disproportionate) discordant ST-segment elevation

Figure 6. Acute partial occlusion of the left main coronary artery. (a) 12-lead electrocardiogram (ECG) with anterior wall STEMI with ST-segment elevation in leads V1 and V2. ST-segment elevation in lead aVR is suggestive of the left main coronary artery as the culprit vessel. In addition, widespread (i.e., >2 anatomic segments) with ST-segment depression. (b) Annotated ECG from “A” with anterior wall STEMI with ST-segment elevation in leads V1 and V2 (small arrows). ST-segment elevation in lead aVR (large arrowhead) is suggestive of the left main coronary artery as the culprit vessel. In addition, widespread (i.e., >2 anatomic segments) with ST-segment depression (large arrows)

Figure 7. Wellens’ syndrome. (a) Deeply inverted T-waves of Wellens’ syndrome, encountered in 75% of cases. 12-lead electrocardiogram (ECG) with similar T-wave abnormalities in leads V3 to V5. (b) Biphasic T-waves of Wellens’ Syndrome, seen in 25% of cases. 12-lead ECG with these T-wave abnormalities in leads V1 to V4