Acute coronary syndrome.

Acute coronary syndrome (ACS) is the umbrella term for the clinical signs and symptoms of myocardial ischemia: unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction. This article further defines ACS and the conditions it includes; reviews its risk factors; describes its pathophysiology and associated signs and symptoms; discusses variations in its diagnostic findings, such as cardiac biomarkers and electrocardiographic changes; and outlines treatment approaches, including drug and reperfusion therapies.