From the Guidelines
When a Lexiscan shows findings compatible with a moderately large apical infarction, the cardiologist should immediately proceed with cardiac catheterization (coronary angiography) to assess coronary artery patency and determine if revascularization is needed. Before the procedure, the cardiologist will start the patient on dual antiplatelet therapy, typically aspirin 325mg loading dose followed by 81mg daily, plus a P2Y12 inhibitor such as ticagrelor 180mg loading dose followed by 90mg twice daily or clopidogrel 600mg loading dose followed by 75mg daily, as recommended by the European Society of Cardiology 1. Anticoagulation with heparin or bivalirudin will be initiated. The cardiologist will also order cardiac biomarkers (troponin, CK-MB), complete blood count, comprehensive metabolic panel, coagulation studies, and a 12-lead ECG. Echocardiography should be performed to assess left ventricular function and potential complications like mitral regurgitation or ventricular septal defect. The patient should receive oxygen if saturation is low, IV access should be established, and pain managed with nitroglycerin or morphine if needed. Beta-blockers and ACE inhibitors may be started if the patient is hemodynamically stable, as suggested by the American College of Cardiology/American Heart Association task force on practice guidelines 1. This comprehensive approach is necessary because apical infarctions typically involve the left anterior descending artery and can lead to significant myocardial damage, heart failure, and electrical instability if not promptly addressed. Risk stratification can identify high-risk and low-risk patients, and in high-risk patients, introduction of GP IIb/IIIa receptor blocker and coronary angiography should be performed during the initial hospitalization, as recommended by the European Society of Cardiology 1.
From the FDA Drug Label
DOSAGE & ADMINISTRATION Myocardial Infarction Early Treatment During the early phase of definite or suspected acute myocardial infarction, initiate treatment with metoprolol tartrate as soon as possible after the patient’s arrival in the hospital. The cardiologist should initiate treatment with metoprolol tartrate as soon as possible after the patient's arrival in the hospital, in a coronary care or similar unit, immediately after the patient's hemodynamic condition has stabilized.
- The treatment should start with the intravenous administration of three bolus injections of 5 mg of metoprolol tartrate injection each, given at approximately 2-minute intervals 2.
From the Research
Next Steps for Cardiologist
When a Lexi scan shows findings compatible with moderately large apical infarction, the cardiologist's next steps may involve:
- Further diagnostic testing to confirm the diagnosis and assess the extent of the damage
- Evaluation of the patient's overall cardiac function and identification of any potential complications, such as ventricular rupture or thrombus formation 3
- Development of a treatment plan, which may include medications such as aspirin, ACE inhibitors, and statins to reduce the risk of further cardiac events 4, 5
- Consideration of invasive procedures, such as coronary angiography or cardiac magnetic resonance imaging (CMR), to guide management and assess the need for interventions such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) 3
Medication Management
The cardiologist may prescribe medications to:
- Reduce the risk of further cardiac events, such as aspirin, ACE inhibitors, and statins 4, 5
- Manage symptoms and prevent complications, such as beta-blockers and nitrates
- Control blood pressure and reduce the risk of myocardial infarction, such as ACE inhibitors 6
Invasive Procedures
The cardiologist may consider invasive procedures, such as:
- Coronary angiography to assess the extent of coronary artery disease and guide management 3
- Cardiac magnetic resonance imaging (CMR) to evaluate cardiac function and identify potential complications, such as ventricular rupture or thrombus formation 3
- Percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) to restore blood flow to the affected area and reduce the risk of further cardiac events 3