Vulnerable/unstable plaque

Erosion and rupture of vulnerable atherosclerotic plaque is the cause of most acute coronary syndromes [32, 33]. Plaque mpture leads to the formation of an intracoronary thrombus, which produces an obstruction that acutely limits coronary artery blood flow, resulting in myocardial ischemia or necrosis. Multiple clinical and autopsy studies have confirmed the pathogenic role of coronary thrombus in cases of acute MI, unstable angina and sudden cardiac death [33, 34]. The lesions that harbor vulnerable plaques are often mildly stenotic on angiographic examination and, consequently, their stability cannot be assessed. The stability of atherosclerotic plaques is related to histological composition Figure 17.2. Unstable plaques typically comprise thin (<65 pm) fibrous caps infiltrated with macrophages that encapsulate lipid-rich necrotic cores with adjacent microcalcification [33, 34]. 

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