Acute Coronary Syndrome
Rupture of an unstable atherosclerotic plaque triggers thrombus formation that partially or completely occludes a coronary artery, and the resulting ECG and troponin pattern (STEMI, NSTEMI, or unstable angina) dictates exactly how urgently the vessel must be reopened.
First principles
One process, a spectrum of severity
Acute coronary syndrome begins when an atherosclerotic plaque's fibrous cap ruptures or erodes, exposing thrombogenic material to flowing blood. Platelets aggregate and a thrombus forms on top of the plaque. If the thrombus is non-occlusive or transient, ischaemia occurs without myocyte death (unstable angina). If it partially occludes the vessel long enough, the innermost, most oxygen-hungry subendocardial myocardium infarcts (NSTEMI). If it completely occludes the vessel, the full thickness of the myocardial wall infarcts (STEMI). One underlying mechanism produces a graded spectrum of severity.
Educational content pending clinical review. Not medical advice.