New insights into atherosclerotic plaque rupture

Abstract

Coronary artery atherosclerosis is the major cause of mortality and morbidity in the indus- trialised world. Progressive narrowing of cor- onary arteries causes angina. However, it is rupture of the plaque that causes the cata- strophic consequences of atherosclerosis, such as myocardial infarction. Recent work has identified that the stability of the plaque rather than its absolute size determines the likelihood of rupture, making a change in plaque compo- sition rather than plaque regression a worth- while clinical goal. This review summarises recent advances in the understanding of plaque rupture, and identifies areas in which new therapies may be directed. The vulnerable plaque Myocardial infarction and unstable angina are caused by rupture or erosion of an atheroscle- rotic plaque, with subsequent thrombus for- mation and occlusion of the artery. The plaque that causes a patient's heart attack is not nec- essarily the one that is identified at angio- graphy. Cardiologists conventionally describe coronary artery stenoses as significant when they occupy >50% of the arterial lumen, that is when they become flow limiting. However, a series of postmortem and angiographic studies has identified that nearly 70% of myocardial infarctions are caused by rupture of plaques that cause 70% stenotic (reviewed by Falk et al 1