From the Guidelines
ST elevation noted on 23AVLAVF indicates an acute coronary occlusion, and the patient should receive immediate reperfusion therapy, either through primary percutaneous coronary intervention (PCI) if available within 90 minutes, or fibrinolytic therapy if PCI is not readily accessible. The management of this condition is guided by the 2017 ESC guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation 1. Initial management includes administering aspirin, P2Y12 inhibitor, anticoagulation with unfractionated heparin, and pain control with morphine if needed. Oxygen should be provided if saturation is below 90%. It's essential to monitor for right ventricular involvement by obtaining right-sided ECG leads, as recommended by the AHA/ACCF/HRS 1. Patients with inferior MIs may develop bradycardia and hypotension due to increased vagal tone, so atropine should be available. The ECG criteria for diagnosing ST-segment elevation myocardial infarction (STEMI) are based on changes of electrical currents of the heart, and the threshold values for abnormal J-point elevation in different leads are provided in the guidelines 1.
Some key points to consider in the management of this patient include:
- The importance of prompt recognition and treatment of STEMI to improve outcomes by limiting myocardial damage and preserving heart function
- The need to monitor for right ventricular involvement and to obtain right-sided ECG leads
- The use of aspirin, P2Y12 inhibitor, anticoagulation with unfractionated heparin, and pain control with morphine as part of the initial management
- The consideration of primary percutaneous coronary intervention (PCI) if available within 90 minutes, or fibrinolytic therapy if PCI is not readily accessible.
The patient's symptoms and ECG findings should be carefully evaluated, and the management plan should be tailored to the individual patient's needs, taking into account the latest guidelines and evidence-based practice 1.
From the Research
ST Elevation Myocardial Infarction (STEMI)
- STEMI is the most acute manifestation of coronary artery disease and is associated with great morbidity and mortality 2
- A complete thrombotic occlusion developing from an atherosclerotic plaque in an epicardial coronary vessel is the cause of STEMI in the majority of cases 2
Diagnosis and Treatment
- Early diagnosis and immediate reperfusion are the most effective ways to limit myocardial ischemia and infarct size and thereby reduce the risk of post-STEMI complications and heart failure 2
- Primary percutaneous coronary intervention (PCI) has become the preferred reperfusion strategy in patients with STEMI; if PCI cannot be performed within 120 minutes of STEMI diagnosis, fibrinolysis therapy should be administered to dissolve the occluding thrombus 2
Electrocardiographic Differentiation
- Acute myocardial infarction with ST elevation in lead aVL may represent involvement of the first diagonal or the first obtuse marginal branch 3
- ST elevation in aVL and V2 through V5 signifies left anterior descending artery occlusion proximal to the first diagonal branch (positive predictive value [PPV] and negative predictive value [NPV] of 95% and 94%, respectively) 3
Treatment with Antiplatelet Therapy
- Ticagrelor improves the clinical outcomes in patients with STEMI undergoing primary percutaneous coronary intervention (PPCI) 4
- Ticagrelor reduces the incidence of major adverse cardiovascular and cerebrovascular events (MACCE) and the composite end point of cardiovascular death, nonfatal MI, and stroke compared with clopidogrel 4
- The use of tirofiban, a nonpeptide glycoprotein IIb/IIIa inhibitor, in STEMI patients treated with dual antiplatelet therapy decreases adverse cardiovascular events after percutaneous coronary intervention for ST-elevation myocardial infarction 5