Updates on Acute Coronary Syndrome: A Review.

IMPORTANCE: Acute coronary syndrome (ACS), the acute manifestation of ischemic heart disease, remains a major cause of morbidity and mortality worldwide and is responsible for more than 1 million hospital admissions in the United States annually. Considerable research is being conducted in the field. This review provides a contemporary overview of key new findings on the pathophysiology, diagnosis, treatment, and prognosis of ACS. OBSERVATIONS: While plaque rupture is the most frequent cause of coronary thrombosis, studies with optical coherence tomography demonstrate that superficial plaque erosion is more common than previously thought. High-sensitivity troponin assays (not yet available in the United States) and cardiac computed tomographic angiography are being increasingly used in diagnosis and risk stratification of patients with suspected ACS. New data from long-term dual antiplatelet therapy studies and investigations of anticoagulants provide important insights into the balance between ischemic and bleeding risks. The added benefit of percutaneous coronary intervention in non-infarct-related arteries in patients with ST-segment elevation myocardial infarction has been demonstrated in randomized trials, and the radial approach has become the standard of care in patients with ACS undergoing angiography. Promising old and new adjunctive therapies, such as pretreatment with β-blockers, ezetimibe, and proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors, are discussed. New guidelines on the management of non-ST-segment elevation ACS were published in the last 2 years, as well as scientific documents on ACS in understudied populations, such as women and patients with renal dysfunction. CONCLUSIONS AND RELEVANCE: Substantial progress in the prevention, diagnosis, and management of patients with ACS has been accomplished in recent years. Despite optimal pharmacological and invasive therapies, the burden of recurrent ischemic events and mortality remains high, and future research is ongoing to prevent and improve the outcome of patients with ACS.