Intravascular hemodynamic factors responsible for progression of coronary atherosclerosis and development of vulnerable plaque

The initiation, localization, growth, composition, and rupture of intracoro nary atheromatous plaque-factors that define the natural history of coronar y artery disease-are all dependent on inhomogenieties and irregularities of intracoronary local blood flow and endothelial shear stress. Restenosis of mechanically recanalized coronary arteries may be related in part to simil ar abnormalities of disturbed local flood flow and shear stress. Low or rev ersed shear stress leads to plaque development and progression. High shear stress contributes significantly to plaque rupture. Regions of hemodynamic stasis caused by major luminal irregularities may lead to thrombosis and my ocardial infarction without plaque rupture. This review outlines the mechan isms that link hemodynamic factors to plaque development and rupture and de scribes in some detail recently developed techniques that, for the first ti me, make it possible to determine these factors in vivo in patients during routine cardiac catheterization procedures. (C) 2000 Lippincott Williams & Wilkins, Inc.