ABSTRACT
INTRODUCTION Cardiovascular disease resulting in myocardial infarction and stroke is the leading cause of mortality worldwide.1 These events are the consequence of atherosclerotic plaque rupture or erosion complicated by thrombosis.2 When the fibrous cap of a thin-cap fibroatheroma is disrupted, its core of thrombogenic material (necrotic tissue, macrophages, and lipids) is exposed to the luminal blood resulting in platelet aggregation and thrombus formation. Thrombosis also occurs without plaque rupture through plaque erosion, a process characterized by proliferation of smooth muscle cells in a proteogylcan matrix and less inflammation.3,4 These events result in either acute coronary syndrome (ACS; that can be fatal) or healing and plaque progression.5,6
Angiography underestimates plaque burden because of vessel remodeling, an increase in arterial dimensions that compensates for and “hides” the accumulating atherosclerotic burden. Studies have shown that events leading to nonfatal ACS events most often occur at sites of moderate, nonlumen compromising disease that is angiographically silent.7-9 These and other shortcomings of angiography led to the development of intravascular ultrasound (IVUS) followed by several second-generation intravascular imaging techniques. This chapter will review the utility of these catheter-based imaging modalities in detecting vulnerable-rupture or thrombosis-prone-plaques in coronary arteries.
