Abstract 11522: Does Neointimal Pattern Predict Instent Thrombus

Introduction: Local determinants of instent thrombus formation after drug-eluting stent (DES) implantation have not been systematically investigated. Hypothesis: Certain neointimal patterns assessed by optical coherence tomography (OCT) may represent local surface thrombogenesity after DES implantation. Methods: A total of 208 patients with 262 DES who underwent follow-up OCT examination 11 months after DES implantation were studied. The detailed OCT findings including characteristics of neointima, lumen size, and stent morphology were compared between the group with and without thrombus. Results: Thrombus was identified in 11.5% (24/208) of the patients. Lipid-laden neointima, thin-cap fibroatheroma, heterogeneous neointima, and extra-stent lumen were more frequently detected in the thrombus group compared to the non-thrombus group (Figure). No difference was found in the % of uncovered (4.9±6.7% vs. 4.2±5.4%; p=0.575) or malapposed struts (1.5±2.5% vs. 0.8±2.1%; p=0.116) between the two groups. Minimal lumen cross sectional area was significantly smaller in the thrombus group compared with the non-thrombus group (2.9±1.7mm 2 vs. 4.6±2.0mm 2 ; p<0.001). Conclusions: Neointimal morphology and smaller lumen cross-section area are important factors associated with instent thrombus.