MORPHOMETRIC AND HISTOLOGIC ASSESSMENT OF REMODELING ASSOCIATED WITH RESTENOSIS AFTER PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY

The role of remodeling in restenosis of coronary arteries on which per cutaneous transluminal coronary angioplasty (PTCA) had been performed was investigated. At autopsy, presence (n = 6) or absence of restenosi s (n = 5) based on the cross-sectional area of stenosis was determined in 11 coronary lesions. Remodeling was defined as a ratio of the arte ry area at the PTCA site to that at the reference site of <1.0. Accord ing to this definition, remodeling had occurred in all of the lesions in the restenosis group, and in only 1 lesion in the group with no res tenosis which had the least residual plaque (p < 0.05). Dense caps of collagen fibers in the adventitia in the vicinity of the disrupted int ernal elastic laminae were present in all of the remodeling lesions. W e suggest that remodeling, which results in adventitial scarring, is o ne of the major causative factors of restenosis.