Overview
Definition
A severe form of Acute Coronary Syndrome (ACS) characterized by transmural myocardial ischemia resulting in myocardial injury or necrosis.
Epidemiology
A true medical emergency requiring immediate reperfusion therapy. Major cause of cardiovascular mortality.
Etiology & Risk Factors
- Complete, acute thrombotic occlusion of a major epicardial coronary artery following plaque rupture
Clinical Symptoms
- Crushing, retrosternal chest pain radiating to the jaw or left arm
- Diaphoresis (profuse sweating)
- Nausea/Vomiting
- Impending doom
Clinical Approach
Diagnosis
- ECG (Diagnostic): New ST-elevation at the J point in ≥ 2 contiguous leads, or new Left Bundle Branch Block (LBBB)
- Cardiac Biomarkers: Troponins will be elevated, but DO NOT delay treatment waiting for results
Management
- Immediate Reperfusion: Percutaneous Coronary Intervention (PCI) within 90 minutes (door-to-balloon time)
- Thrombolytics (Alteplase) within 30 minutes if PCI is unavailable and transport > 120 mins
- Medical therapy: Aspirin, P2Y12 inhibitor, Heparin, Beta-blocker, Statin, Nitroglycerin (unless right ventricular infarct)
Complications
- Ventricular Arrhythmias (V-Fib)
- Cardiogenic Shock
- Papillary muscle rupture (Acute MR)
- Ventricular free wall rupture
- Dressler Syndrome (post-MI pericarditis)