LAUSR

Non-ST elevation-acute coronary syndrome (NSTE-ACS) includes NSTE myocardial infarction and unstable angina. This patient population forms approximately two-thirds of all hospital admissions for ACS in the United States each year and is associated with an in-hospital mortality of 5%. NSTE-ACS is primarily due to an acute change in the supply and demand balance of coronary perfusion and myocardial oxygen consumption, because of the significant coronary artery obstruction presenting as plaque rupture or erosion. Nevertheless, nonobstructive causes may lead to that same phenomenon by excessive myocardial oxygen demand or reduced coronary supply from hypotension, anemia, or sepsis, including transient coronary vasospasm and endocardial dysfunction. The recent clinical application of high-sensitivity troponin biomarker assays and computer tomography angiography shows promise for improving the diagnosis and the risk stratification of patients with angina symptoms. Implementation of recent updates to the American College of Cardiology/American Heart Association (ACC/AHA) guidelines on NSTE-ACS, especially regarding the selection and duration of antiplatelet therapy, have led to improvement in management and outcomes of this disease. Additionally, new adjunctive therapies and approaches to diagnosis and treatment are discussed. Despite the progress made in recent years in the diagnosis and management of NSTE-ACS, morbidity remains high and mortality is significant. Such a fact suggests that future research targeting prevention, early diagnosis, and intervention in these patients is warranted. This article provides a detailed overview of the most recent information on the pathophysiology, diagnosis, treatment, and prognosis of NSTE-ACS.