Ex Vivo Assessment of Neointimal Characteristics After Drug-eluting Stent Implantation: Optical Coherence Tomography and Histopathology Validation Study

• Published in: International journal of cardiology 2016-10, Vol.221, p.1043-1047
• Main Authors: Imanaka, Takahiro, Fujii, Kenichi, Hao, Hiroyuki, Shibuya, Masahiko, Saita, Ten, Kawakami, Rika, Fukunaga, Masashi, Kawai, Kenji, Tamaru, Hiroto, Miki, Kojiro, Horimatsu, Tetsuo, Sumiyoshi, Akinori, Nishimura, Machiko, Hirota, Seiichi, Masuyama, Tohru, Ishihara, Masaharu
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Atherosclerosis - diagnosis; Atherosclerosis - etiology; Autopsy; Cardiovascular; Coronary Artery Disease - diagnosis; Coronary Artery Disease - pathology; Coronary Artery Disease - surgery; Coronary Vessels - diagnostic imaging; Coronary Vessels - pathology; Dimensional Measurement Accuracy; Drug-eluting stent; Drug-Eluting Stents - adverse effects; Female; Histology; Humans; Male; Middle Aged; Neointima - diagnostic imaging; Neointima - pathology; Optical coherence tomography; Percutaneous Coronary Intervention - adverse effects; Percutaneous Coronary Intervention - instrumentation; Percutaneous Coronary Intervention - methods; Reproducibility of Results; Tomography, Optical Coherence - methods
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/j.ijcard.2016.07.110

Abstract Background Optical coherence tomography (OCT) is one of the tools trying to distinguish neoatherosclerosis from other neointimal tissue but its role has to be still validated. This study evaluated the diagnostic accuracy of OCT for characterization of lipid-atherosclerotic neointima following drug-eluting stent (DES) implantation. Methods Twelve stented coronary arteries from the 7 autopsy hearts were imaged by OCT. These OCT images were compared with histology. By OCT, the morphological appearances of neointima were classified into three patterns: homogeneous pattern, heterogeneous pattern with visible strut, or heterogeneous pattern with invisible strut. Results Of 21 histological cross-sections, 6 were categorized as homogeneous patterns (29%), 11 as heterogeneous patterns with visible stent strut (52%), and 4 as heterogeneous patterns with invisible stent strut (19%). All homogeneous patterns were composed of smooth muscle cells with collagen fibers. The heterogeneous patterns with visible stent strut included proteoglycan-rich myxomatous matrix and calcium deposition. On the other hand, the heterogeneous patterns with invisible stent strut comprised atheromatous tissue, including a large amount of foam cell accumulation (25%) or large fibroatheroma/necrotic core (75%) inside the stent struts within neointima. The optical attenuation coefficient was highest in the heterogeneous pattern with invisible stent strut due to scattering of light by atheromatous tissue. Conclusion The heterogeneous patterns with invisible stent strut on OCT imaging identifies the presence of lipid-atherosclerotic tissue within neointima after DES. This may suggest the potential capability of OCT based on visualization of stent struts for discriminating atheromatous formation within neointima from other neointimal tissue.