Eccentric, lipid-rich atherosclerotic plaques are at risk of fissuring due to vessel spasm or changes in blood flow or pressure. Fissuring of the plaque frequently leads to superimposed thrombosis, with acute partial or total occlusion of the vessel lumen. The lumen of this coronary artery is almost completely occluded by recent thrombus. Occlusion of flow will result in infarction of the myocardium if flow is not restored within 20-40 minutes. A thrombus may lyse spontaneously or may fragment and embolize to smaller caliber vessels.
Thrombolytic therapy is currently an important part of management of acute myocardial infarction.
In a coronary artery this complication may lead to an increase in plaque dimension and potentially cause abrupt reduction of the vessel lumen.