Abstract 3062: Evaluation of Long-term Changes of Neointimal Coverage on Sirolimus-eluting Stents by Optical Coherence Tomography
BACKGROUND Long term condition of neointimal coverage on Sirolimus-eluting stents (SES) remains to be clarified. Optical coherence tomography (OCT) with an excellent resolution visualizes thin neointima on SES struts which intravascular ultrasound (IVUS) can not detect.
METHOD OCT was fulfilled in 13 SES at 6 month (M) and 12 M after SES deployment. Stent strut apposition to the vessel wall and intimal coverage on each strut was evaluated with every 1 mm cross section.
RESULTS OCT visualized 1501 struts cross sections at 6 M and 1668 struts at 12 M. Frequency of struts cross sections without neointimal coverage decreased from 8.6% (6M) to 3.0% (12M) (P<0.0001). On the other hand, neointima which covered the struts at 6M showed no apparent increase in its thickness (82.6±92.9μm vs 86.4±89.5μm P=0.28).
CONCLUSION From 6M to 12M, further neointimal coverage on uncovered struts was observed, while the thickness of preexisting neointima on struts did not change. This suggests the delayed reendothelialization without late catche-up restenosis in SES.