Newer Concepts Regarding Adults With Coronary Artery Aneurysms

Abstract

The most commonly accepted definition of coronary aneurysm (CA) is an enlargement of a coronary arterial segment to more than 50% of the distal reference diameter.1,2 This definition generally refers to the inner diameters of the vessels as determined by coronary angiography. Computerized axial tomographic (CAT) imaging is currently the preferred method of studying CA, especially for longitudinal studies of the extent and severity of dilatation, calcification, mural thrombosis, and stenosis.3 Only tomographic imaging can quantitatively describe vascular wall thickening, a hallmark of the disease progression and prognosis in a post-arteritis CA. Additionally, the 50% definition can be inaccurate: in cases with diffuse dilatation, the reference diameter can become difficult to identify.2 The 50% rule may or may not carry prognostic value, which is the main clinical goal of classifying a coronary segment as ectasic or anomalous. The essential clinical interest is in differentiating a CA from the Glagov phenomenon, the mild dilatation of the outer diameter of a coronary artery seen in early atherosclerotic degenerative disease. According to the Glacov theory, the outer diameter of the coronary arteries dilates in the early phases of atherosclerosis, when plaque deposition leads to positive remodeling with preservation of the vessel lumen.4 Such positive remodeling probably does not allow for a dilatation of the coronary artery greater than 50% of the previous normal diameter. (SELECT FULL TEXT TO CONTINUE)