Abstract 11302: The Morphological Findings Of Very Late In-stent Restenosis After Bare-metal Stent Implantation: Optical Coherence Tomography Analysis
Purpose: Although In-stent restenosis (ISR) after bare-metal stent (BMS) implantation peaks in the early phase, late ISR is occasionally observed beyond a few years after implantation. The mechanism has not been fully clarified yet. We evaluated the morphologic characteristics of very late ISR (VLISR: later than 5 years without angiographic restenosis within 1 year), compared early ISR (EISR: within 1 years) using OCT.
Method: The parameters of morphological characteristics (normal neointima, calcification, lipid-laden, thin cap fibroathroma like intima, disrupted or ruptured plaque like intima) were evaluated not only minimal lumen diameter (MLD) site but also non-MLD site. In addition, the presence of thrombus and microvessels were also analyzed.
Result: OCT findings of 30 VLISR lesions compared to those of 30 EISR lesions. At MLD site, The incidence of atheroscrelotic plaque components were significant higher in VLISR group than EISR group not only MLD site (lipid-laden 100% vs 0%, TCFA like intima 40% vs 0%, disrupted or ruptured plaque like intima 40% vs 0%, respectively; p<0.05) but also non-MLD site (lipid-laden 81.8% vs 0%, calcification18.5% vs 0%, TCFA like intima 25.9% vs 0%, disrupted or ruptured plaque like intima 25.9% vs 0%, respectively; p<0.05). Thrombus and intraintima microvessels were only detected in VLISR at both sites.
Conclusion: The morphological characteristics of tissue structure with VLISR were different from those of EISR, which were similar to an atherosclerotic plaque of coronary artery. The late restenosis of BMS may be associated with the reprogression of atherosclerosis in the neointimal proliferation of the stent
- © 2010 by American Heart Association, Inc.