Arterial remodeling and coronary artery disease: The concept of "dilated" versus "obstructive" coronary atherosclerosis

Traditionally, the development of coronary artery disease (CAD) was describ ed as a gradual growth of plaques within the intima of the vessel. The oute r boundaries of the intima, the media and the external elastic membrane (EE M), were thought to be fixed in size. In this model plaque growth would alw ays lead to luminal narrowing and the number and severity of angiographic s tenoses would reflect the extent of coronary disease. However, histologic s tudies demonstrated that certain plaques do not reduce luminal size, presum ably because of expansion of the media and EEM during atheroma development. This phenomenon of "arterial remodeling" was confirmed in necropsy specime ns of human coronary arteries. More recently", the development of contempor ary imaging technology, particularly intravascular ultrasound, has allowed the study of arterial remodeling in vivo. These new imaging modalities have confirmed that plaque progression and regression are not closely related t o luminal size. In this review, we will analyze the role of remodeling in t he progression and regression of native CAD, as well as its impact on reste nosis after coronary intervention. (J Am Coll Cardiol 2001;38:297-306) (C) 2001 by the American College of Cardiology.