Clinical significance of neoatherosclerosis observed at very late phase between 3 and 7 years after coronary stent implantation

Abstract Background Clinical significance of neoatherosclerosis (NA) observed at very late phase remains undetermined. We sought to investigate the association between NA observed by optical coherence tomography (OCT) 3–7 years after stenting and subsequent clinical outcomes. Methods We investigated previously implanted stents without stent failure in the institutional OCT database at Tsuchiura Kyodo General Hospital. Qualitative and quantitative OCT analyses were performed. In patient-based analysis, major adverse cardiac events (MACE) included all-cause death, non-fatal myocardial infarction, and clinically driven revascularization. MACE-free survival rate was compared between patients with any stent showing NA (NA group) and those without NA (non-NA group). In stent-based analysis, the stent failure including target-lesion revascularization and stent thrombosis after the belated OCT examination were assessed. Results A total of 187 patients with 308 stents undergoing belated OCT examination 3–7 years after implantation were investigated. Median duration from implantation to the belated OCT was 4.8 (3.8-5.8) years and NA was identified in 48 stents (15.6%) in 36 patients (19.3%). In patient-based analysis, during the median of 2.9 (2.1-3.6) years after belated OCT, MACE occurred in 9 patients (25.0%) with at least one stent showing NA (NA group) and 9 patients (6.0%) without NA (non-NA group) (p=0.002). Cox regression analysis revealed that NA was an independent predictor of MACE [hazard ratio (HR) 4.14 (1.58- 10.8), p=0.004]. In stent-based analysis, 7 stent failures were documented (stents with NA 10.0% vs. stents without NA 0.8%, p Conclusions NA observed by OCT 3-7 years after implantation was associated with subsequent worse clinical outcomes in both patient-based and stent-based analysis.