Your choice: Atherosclerotic plaque rupture 
					Rupture of an atherosclerotic plaque is usually not the etiology of stable angina pectoris.  Plaque rupture may initiate thrombus formation.  When the thrombus is non-occlusive, the result may be unstable angina.  An occlusive thrombus precipitates the majority of ST-segment elevation myocardial infarctions.