The term acute coronary syndrome  (ACS) refers to any group of clinical symptoms compatible with acute myocardial ischemia and includes unstable angina (UA), non—ST-segment elevation infarction (NSTEMI), and ST-segment elevation infarction (STEMI). These high-risk manifestations of coronary atherosclerosis are important causes of the employment of emergency medical aid and hospitalization within the us. a fast but thorough assessment of the patient's history and findings on physical examination, electrocardiography, radiologic studies, and cardiac biomarker tests permit accurate diagnosis and aid in early risk stratification, which is important for guiding treatment. High-risk patients with UA/NSTEMI are often treated with an early invasive strategy involving cardiac catheterization and prompt revascularization of viable myocardium in danger. Clinical outcomes is optimized by revascularization not to mention aggressive medical therapy that features anti-ischemic, antiplatelet, anticoagulant, and lipid-lowering drugs. Evidence-based guidelines provide recommendations for the management of ACS; however, therapeutic approaches to the management of ACS still evolve at a rapid pace driven by a mess of large-scale randomized controlled trials. Thus, clinicians are frequently faced with the matter of determining which drug or therapeutic strategy will achieve the simplest results. this text summarizes the evidence and provides the clinician with the newest information about the pathophysiology, clinical presentation, and risk stratification of ACS and therefore the management of UA/NSTEMI. The term acute coronary syndrome (ACS) refers to any group of clinical symptoms compatible with acute myocardial ischemia and covers the spectrum of clinical conditions starting from unstable angina (UA) to non—ST-segment elevation infarction (NSTEMI) to ST-segment elevation infarction (STEMI).