ST elevation: differentiation between ST elevation myocardial infarction and nonischemic ST elevation
Section snippets
“Concave” versus “convex” pattern of STE
The ST segment reflects ventricular depolarization and is normally isoelectric with the PR and TP segments. It is commonly taught that STE in which the ST segment morphology is upwardly convex or straight is consistent with STEMI compared with a concave morphology, which is associated with NISTE. The ACC/AHA guidelines suggest that it is less likely that STEMI is present if the upward-directed ST-segment changes are concave rather than convex.1 However, Smith16 reported that 43% of patients
Early repolarization
The typical pattern of early repolarization NISTE shows STE of 1-4 mm in the lateral leads (mainly V5-V6). It may also involve the inferior leads. There is a characteristic notch at the J-point (Fig. 2). The ST segment is usually concave, and tall, peaked T waves may be present. Early repolarization NISTE is commonly seen in young males. In many cases, STE is transient and ameliorates or even disappears with tachycardia and hyperventilation. Thus, dynamic changes in the degree of STE are not
A “normal-variant” pattern of NISTE
A “normal-variant” STE is defined as ST elevation mainly in leads V1-V3 (Fig. 4).5 It is common in young males, mainly African American and Hispanic. In contrast to the NISTE seen in patients with left ventricular hypertrophy (LVH), there are no QRS criteria for LVH present and there is no concomitant ST depression in the lateral leads. Some investigators do not differentiate between a “normal variant” pattern and “early repolarization” pattern, lumping all together as “early repolarization.”
STE secondary to LVH
NISTE secondary to LVH is typically seen in leads V1-V3. Usually, there are QRS criteria for LVH and concomitant ST depression in the lateral leads V5-V6 (Fig. 5). In many cases, there is also STE in lead aVR. It is important not to confuse this pattern with the pattern reported to be related to left main related or global ischemia (STE in leads aVR and V1 with ST depression in the inferior and anterolateral leads). It should be remembered that, according to the “Universal Definition of
Acute pericarditis
The classical ECG pattern of acute pericarditis is diffuse STE in all leads, except leads V1 and aVR, which instead may show ST depression (Fig. 7). Typically, the pattern of STE in pericarditis does not fit a single vascular territory. Depression of the PR interval below the isoelectric line is commonly seen early in the course of pericarditis. However, focal pericarditis after STEMI or cardiac surgery may result in more localized and atypical forms of STE, which may manifest ST depression in
STE secondary to IVCD
LBBB is commonly associated with marked ST changes (Fig. 8). ST deviation is usually discordant to the direction of the major deflection of the QRS complex due to presence of secondary ST-T wave abnormalities. Acute myocardial infarction, on the other hand, is more likely to present with primary ST-T wave abnormalities (ie, deviation that is concordant to the QRS complex.) Because patients with LBBB usually have negative QRS deflections in leads V1-V3, they usually display prominent STE in
Brugada syndrome
The Brugada pattern of NISTE shows an RBBB pattern with STE in the anterior leads.31, 32 The Brugada syndrome is associated with a high risk for ventricular tachyarrhythmia and sudden cardiac death. Type 1 Brugada is characterized by a coved STE >0.2 mV, followed by a negative T wave in >1 right precordial leads (V1-V3) in the presence or absence of a sodium channel blocker and in conjunction with documented ventricular fibrillation, polymorphic ventricular tachycardia, a family history of
Takotsubo syndrome (apical ballooning syndrome)
Apical ballooning syndrome is more common in postmenopausal women and classically occurs following acute emotional or physiologic stress. Patients present with chest pain and/or shortness of breath, and their ECG may show STE (81.6% of the patients, mainly in the precordial leads), T-wave abnormalities (64.3%) and Q waves (31.8%). Mild elevation of cardiac markers has been reported in 86.2% of the patients.34 In many cases, the initial presentation is indistinguishable from anterior STEMI,
Spontaneously reperfused STEMI
The current guidelines for STEMI recommend that patients with suggestive symptoms of myocardial ischemia within the preceding 12 hours presenting with STE in ≥2 adjacent ECG leads (>0.1 mV at the J-point) should undergo immediate reperfusion therapy.1 The guidelines do not mention the entity of (spontaneously) reperfused STEMI at all, and they do not mention ongoing symptoms as a prerequisite for immediate reperfusion therapy. A large number of patients may have (partial) resolution of symptoms
Left ventricular aneurysm
Left ventricular aneurysm is another diagnosis to be aware of as it may cause persistent STE after a previous myocardial infarction that, at times, may be indistinguishable from acute STEMI. Diagnosis is especially difficult when previous ECG tracings are unavailable. At one hospital in Minnesota, a patient received systemic thrombolytics on 2 separate occasions in the emergency room because of chronic STE from a previous LV aneurysm after an old MI (//hqmeded-ecg.blogspot.com/2008/11/65-yo-male-with-recent-rule-out.html
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Role of Positive Emotions in Takotsubo Cardiomyopathy
2023, Current Problems in CardiologyCatch Me If You Can: ECG Artifacts
2023, American Journal of MedicineValidation of the vessel-specific leads (VSLs) for detection of acute ischemia on a dataset with non-ischemic ST-segment deviation
2016, Journal of ElectrocardiologyCitation Excerpt :In a previous study [5], we have shown that the 3 vessel-specific leads (VSLs) derived from conventional 12-lead ECG can improve sensitivity (SE) of acute myocardial ischemia detection without any loss of specificity (SP). However, the two test datasets – the STAFF III dataset [6] acquired during controlled acute ischemia and the Glasgow dataset [7] collected from patients who were hospitalized for chest pain – contain few ECGs with non-ischemic ST deviation that are known to cause false-positive STEMI detection [8]. Therefore, the present study aimed at evaluating specificity of the VSLs method, using a dataset with non-ischemic ST-segment changes.
El-Sherif sign and lateral ST segment elevation in hypertrophic cardiomyopathy associated with apical aneurysm
2016, International Journal of CardiologyAssociation of ST elevation with apical aneurysm in hypertrophic cardiomyopathy
2015, Indian Heart JournalCitation Excerpt :The other rare variant of MVO-HCM, which was first reported by Falicov et al in 1976, is characterized by the presence of pressure gradient between the apical and basal chambers of the left ventricle, and is also frequently associated with an apical aneurysm without significant atherosclerotic coronary artery disease.11 Classically left ventricular apical aneurysm has been considered a complication of acute myocardial infarction, but also has been reported as associated with HCM, Chagas' disease, sarcoidosis, congenital or idiopathic.12 In most cases, the chronic apical aneurysm in the presence of the previous myocardial infarction manifested electrocardiographically by varying degrees of chronic STE.12
High-risk ECG patterns in ACS - Need for guideline revision
2013, Journal of ElectrocardiologyCitation Excerpt :The current guidelines suggest that patients presenting without STE can be initially managed conservatively and coronary angiography can be performed later to prevent reinfarction, but not to save myocardium. However, many patients presenting with chest pain may have STE secondary to nonischemic etiologies.3 Many classic patterns of nonischemic STE can be easily identified (early repolarization, normal pattern, pericarditis, etc).