From the Guidelines
An EKG showing anterolateral ST-elevation with repolarization variant likely represents benign early repolarization rather than acute myocardial infarction. This pattern is typically characterized by ST-segment elevation in the anterolateral leads (V2-V6, I, aVL) with upward concavity ("smiley face" appearance), notching or slurring at the J-point, and tall T waves in the same distribution. No specific treatment is needed for benign early repolarization as it is a normal variant found in up to 5-13% of the population, particularly in young, athletic males and those of African descent. To differentiate this from concerning pathology, look for these key features: ST elevation is usually less than 2mm, there's absence of reciprocal ST depression, no significant Q waves, and the patient lacks chest pain or other cardiac symptoms. Serial EKGs showing stability of the pattern over time can help confirm the benign nature. If clinical suspicion for acute coronary syndrome exists despite these features, cardiac biomarkers should be checked and cardiology consultation obtained, as suggested by the American Heart Association 1. The physiologic basis for early repolarization involves variations in ion channel function during phase 1 and 2 of the cardiac action potential, creating the characteristic ECG appearance without representing actual myocardial injury.
Some key points to consider in the diagnosis of early repolarization include:
- The presence of ST-segment elevation in the anterolateral leads with a characteristic "smiley face" appearance
- The absence of reciprocal ST depression and significant Q waves
- The lack of chest pain or other cardiac symptoms
- The stability of the EKG pattern over time
It's also important to note that other conditions, such as pericarditis, myocarditis, and coronary artery occlusion, can cause similar EKG changes, and a thorough clinical evaluation is necessary to determine the underlying cause of the EKG findings, as discussed in the American College of Cardiology guidelines 1. Additionally, the use of cardiac biomarkers and cardiology consultation can help to confirm the diagnosis and guide treatment, as recommended by the American Heart Association 1.
In terms of the evidence, the most recent and highest quality study on this topic is the 2017 update to practice standards for electrocardiographic monitoring in hospital settings, which provides guidance on the interpretation of EKG findings, including early repolarization 1. This study, along with others, such as the 2009 AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram 1, and the 2012 third universal definition of myocardial infarction 1, support the diagnosis of early repolarization as a benign condition.
From the Research
EKG Findings
- Anterolateral ST-elevation is a significant finding on an electrocardiogram (EKG) that may indicate a myocardial infarction (MI) or acute coronary syndrome (ACS) 2.
- Repolarization variant is a term that refers to changes in the EKG that occur during the repolarization phase of the cardiac cycle, which can be a normal variant or associated with various cardiac conditions.
Clinical Implications
- The presence of anterolateral ST-elevation on an EKG suggests the need for immediate medical attention and further evaluation for ACS or MI 3, 2.
- The management of ACS or MI involves a combination of antiplatelet, anticoagulant, and other medical therapies, as well as potential revascularization procedures such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) 3, 4, 5.
Treatment Options
- Antiplatelet therapy with aspirin and a second antiplatelet agent, such as clopidogrel or ticagrelor, is recommended for patients with ACS or MI 3, 4.
- Anticoagulation therapy with unfractionated heparin, low-molecular-weight heparin, or fondaparinux may also be used in the management of ACS or MI 3, 5.
- PCI with stent placement is a recommended treatment for patients with ST-segment elevation MI, and should be performed as soon as possible 3, 2.