cardiovascular disorders
Overview of Acute Coronary Syndromes (ACS)
Key Points
Unstable angina, NSTEMI, and STEMI represent worsening degrees of myocardial ischemia and necrosis; the distinctions help differentiate prognosis and guide treatment. Diagnosis is based on serial ECG and cardiac marker levels, particularly using new, highly sensitive troponin T tests. Immediate medical treatment depends on the specific syndrome and patient characteristics but typically involves antiplatelet drugs, anticoagulants, beta-blockers, and nitrates as needed (eg, for chest pain, hypertension, pulmonary edema), and a statin to improve prognosis. For unstable angina and NSTEMI, do angiography within 24 to 48 hours of hospitalization to identify coronary lesions requiring PCI or CABG; fibrinolysis is not helpful. For STEMI, do emergency PCI when door to balloon-inflation time is<90 minutes; do fibrinolysis if such timely PCI is not available. Following recovery, initiate or continueaspirinand other antiplatelet drugs, beta-blockers, ACE inhibitors, and statins in most cases unless contraindicated. 