Editing Coronary artery disease (section)

===Acute coronary syndrome===
{{main|Acute coronary syndrome}}
Diagnosis of [[acute coronary syndrome]] generally takes place in the [[emergency department]], where ECGs may be performed sequentially to identify "evolving changes" (indicating ongoing damage to the heart muscle). Diagnosis is clear-cut if ECGs show elevation of the "[[Electrocardiogram#ST segment|ST segment]]", which in the context of severe typical chest pain is strongly indicative of an acute [[myocardial infarction]] (MI); this is termed a STEMI (ST-elevation MI) and is treated as an emergency with either urgent [[Coronary catheterization|coronary angiography]] and [[percutaneous coronary intervention]] (angioplasty with or without [[stent]] insertion) or with [[thrombolysis]] ("clot buster" medication), whichever is available. In the absence of ST-segment elevation, heart damage is detected by [[cardiac marker]]s (blood tests that identify heart muscle damage). If there is evidence of damage ([[infarction]]), the chest pain is attributed to a "non-ST elevation MI" (NSTEMI). If there is no evidence of damage, the term "unstable angina" is used. This process usually necessitates hospital admission and close observation on a [[coronary care unit]] for possible complications (such as [[cardiac arrhythmia]]s – irregularities in the heart rate). Depending on the risk assessment, stress testing or angiography may be used to identify and treat coronary artery disease in patients who have had an NSTEMI or unstable angina.{{Citation needed|date=January 2021}}