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

Background: Clinical significance of neoatherosclerosis (NA) observed at very late phase remains undeter-mined. 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 my-ocardial 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 < 0.01). NA was a significant predictor of stent failure [HR 9.17 (1.67-50.3), p = 0.011] at OCT examinations. 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. (c) 2021 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Automated summary

Neoatherosclerosis observed by optical coherence tomography (OCT) at 3-7 years after stenting is associated with worse subsequent clinical outcomes, serving as an independent predictor for major adverse cardiac events (MACE) and stent failure.