Optical Coherence Tomography Evaluation of Zotarolimus-eluting Stents at 9 Month Follow Up: Comparison with Sirolimus-eluting stents

Jung-Sun Kim ¹, Ik-Kyung Jang ², Jin-Sun Kim ¹, Tae Hoon Kim ¹, Masamichi Takano ³, Teruyoshi Kume ⁴, Nam Wook Hur ¹, Young-Guk Ko ¹, Donghoon Choi ¹, Myeong-Ki Hong ¹ and Yangsoo Jang ^1*

¹ Yonsei University, Korea, Republic of
² Massachusetts general hospital, Harvard Medical schol, United States
³ Nippon Medical School, Japan
⁴ Kawasaki Medical School, Japan

^* To whom correspondence should be addressed. E-mail: jangys1212{at}yuhs.ac.

Accepted 26 May 2009

Abstract

Objective: To evaluate the vascular response at 9 months after zotarolimus-eluting stent (ZES) implantation using optical coherence tomography (OCT). These findings were compared with those after sirolimus-eluting stent (SES).

Design: Cross-sectional observational study with prospective OCT registry.

Setting: Nine months after ZES or SES implantation.

Design and patients: A total of 68 patients (32 ZES and 36 SES) underwent OCT procedure at 9 months after stent implantation. NIH (neointima hyperplasia) thickness inside each strut and percentage of NIH area at every 1 mm cross-section were measured.

Main outcome measurement: The degree of neointimal coverage and the prevalence of malapposition at 9 months after ZES and SES implantation using OCT.

Results: The mean NIH thickness (251.2±110.0 µm vs. 85.5±53.3 µm, p<0.001) and percent of NIH area (27.9±9.2 % vs. 11.2±7.1 %, p< 0.001) were significantly greater in ZES as compared to SES. The prevalence of exposed strut as well as malapposed strut were significantly lower in ZES (0.3 % vs. 12.2 %, p<0.001 and 0.01 % vs. 2.6 %, p<0.001). Thrombus was not observed in ZES (0.0 % in ZES vs. 27.8 % in SES, P = 0.001).

Conclusions: Neointimal coverage in ZES was almost complete and malapposition was very rare at 9-month follow up.