Abstract 15334: Association Between Angiographic Restenosis Patterns and Morphologic Characteristics Evaluated by Optical Coherence Tomography in In-Stent Restenosis Lesions
Background: The morphological assessment of neointimal tissue using optical coherence tomography (OCT) is highly significant to clarify the pathophysiology of in-stent restenosis (ISR). Little is known about the association between angiographic restenosis patterns and morphologic characteristics evaluated by OCT in ISR lesions. The objective of this study was to clarify the difference in tissue characteristics of ISR lesions between angiographic restenosis patterns.
Methods and Results: Between May 2008 and May 2012, we assessed the morphologic characteristics of 347 ISR lesions in 261 patients using OCT. The morphological assessment of neointimal tissue at the minimum lumen area site, including restenotic tissue structure (homogeneous, heterogeneous and layer type), restenotic tissue backscatter, visible microvessels, lumen shape, red or white thrombus, lipid-rich plaque (lipid arc more than 90 degrees), thin-cap fibroatheroma (TCFA, the thinnest fibrous cap thickness less than 65 μ m), disruption of intima, and macrophage was performed. Restenosis patterns were classified into two groups according to Mehran classification: Focal group (218 lesions) and Diffuse group (129 lesions). The patients were 208 men and 53 women, and the mean age was 68.9±9.7 years. Layered intima was observed more frequently in the Focal group than in the Diffuse group (55.0% vs. 43.4%, p<0.05). Lipid-rich plaque was observed more frequently in the Focal group than in the Diffuse group (60.6% vs. 48.8%, p<0.05). Red thrombus was observed more frequently in the Diffuse group than in the Focal group (14.7% vs. 7.3%, p<0.05). There was no significant difference in other factors between two groups. The difference in distribution of restenotic tissue structure depending on the timing of appearance of restenosis is shown in the figure.
Conclusion: The pathophysiology of ISR might be different depending on the angiographic restenosis pattern.
- © 2012 by American Heart Association, Inc.