Abstract 16128: Vascular Healing Response After Everolimus Eluting Stent Implantation in Patients With or Without Diabetes Mellitus -Evaluation With Optical Coherence Tomography

Introduction: Clinical introduction of percutaneous coronary intervention (PCI) with drug eluting stent has substantially decreased the rate of in-stent restenosis (ISR). However, it is reported that patients with diabetes mellitus (DM) still have higher incidence of restenosis and secondary cardiovascular events than patients without DM. Using intravascular optical coherence tomography (OCT), we evaluated the effect of DM on healing process of coronary artery after everolimus eluting stents (EES) implantation in the comparison with non-DM patients. Methods and Results: We studied 26 DM patients (65.1±11.9y/o) and 59 non-DM patients (68.1±9.4y/o) who received OCT-guided EES implantation. The second OCT examination was performed on 296±71.1 days after implantation (291±74.2days vs. 298±70.3days, p=0.51). OCT cross-sectional images of the second study were examined to determine the condition of neointimal coverage over every strut in 1mm interval (DM; 725 cross-sections and 5742 struts, non-DM; 1482 cross-sections and 12098 struts). In addition, neointimal thickness (NIT) over each strut measured and tissue characteristics were examined. One in-stent restenosis with clinical manifestation was observed in each group. Average NIT was significantly thicker in DM group than in non-DM group (107±99.2μm vs. 92±74.6μm, p<0.01). The incidence of malapposed struts without neointimal coverage were very low and similar in both groups (0.22±0.54 vs. 0.13±0.72%, p=0.43). The frequency of OCT-defined unstable neointimal characteristics was significantly higher rate in DM than non-DM group (14.5±18.9% vs. 6.67±14.5%, p=0.03). Conclusions: EES implanted in DM patients showed acceptable neointimal proliferation and uncovered stent struts similar to non-DM patients, suggesting the mid-term efficacy and safety of EES in DM patients. However, long-term follow-up should be necessary because of the high incidence of unstable neointimal characteristics which might be a substrate for the future development of neoatherosclerosis.