Abstract 17576: Continual Delayed Arterial Healing 5 Years after Implantation of Sirolimus-Eluting Stents: Serial Observations by Coronary Angioscopy
Objectives: Very late stent thrombosis increasing steadily is caused by delayed healing within the SES segments, morphological changes of the coronary lumen over 2 years have not been validated in living patients. The very late vascular response to sirolimus-eluting stents (SES) is evaluated by serial angioscopic observations from 2 to 5 years.
Methods and Results: Serial angioscopic observations were collected for 17 segments in 17 patients treated with SES at 2 and 5 years. Neointimal stent coverage (NSC) was classified as follows: grade 0=presence of uncovered struts; grade 1=visible struts through thin neointima; or grade 2=complete neointimal coverage without visible struts. For each patient, the minimum and maximum NSC grade and the existence of in-stent thrombus were estimated. Neither minimum nor maximum NSC grade increased between 2-year and 5-year (0.59±0.51 vs. 0.88±0.70; P=0.17 and 1.82±0.39 vs. 1.94±0.24; P=0.30, respectively). Prevalence of patients with uncovered struts did not significantly decrease from 2 to 5 years (41% vs. 29% P=0.49). During the follow-up, 3 of 6 thrombi disappeared, whereas new thrombus formation was found in 3 patients without any clinical symptoms, and in-stent thrombus did not decrease (35% vs. 35% P>0.99).
Conclusions: The current serial angioscopic study showed that incomplete NSC and latent thrombus within the SES segments did not diminish from 2 to 5 years. Thrombogeneity resulting from incomplete healing of SES may continue for an extended period of time.
- © 2010 by American Heart Association, Inc.