Abstract 13746: Relationships between Neointimal Tissue Characteristics and Occurrence of Periprocedural Myocardial Infarction in Lesions with In-Stent Restenosis

Abstract

Background: Recent studies have reported several types of neointimal tissues including neoatherosclerotic progression in stent restenosis. However, the influence of neointimal tissue characteristics on outcomes after percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) remains unclear. Periprocedural myocardial infarction (PMI) is related to poor outcomes after PCI. We assessed relationships neointimal tissue characteristics and occurrence of PMI after PCI in ISR lesions. Methods: We investigated 45 ISR lesions in 45 stable angina pectoris (SAP) patients who underwent pre- and post-PCI coronary angioscopy (CAS) and optical coherence tomography (OCT) examination. We excluded patients with hemodialysis. All lesions were divided into lesions with PMI, defined as high-sensitivity cardiac troponin-T (hs-cTnT) values after PCI ≥5 times of the upper reference limit in patients with normal baseline values or ≥5 times of baseline values if hs-cTnT values were elevated before PCI, and those without. Clinical and lesion characteristics including intrastent neointimal tissues were compared between two groups. Results: PMI was observed in 15 (33.3%) lesions. Clinical characteristics including stent types and terms after stenting were similar between lesions with and without PMI. CAS analysis showed higher frequency of white neointimal proliferation with irregular surface or yellow neointima at the culprit site before PCI (86.7% vs. 43.3%, p=0.009) and atheromatous appearance (CAS-AP), defined as yellow plaque including complex thrombi underneath disrupted neointimal coverage after ballooning (66.7% vs. 16.7%, p=0.003) in lesions with PMI than those without. OCT analysis demonstrated higher frequency of heterogeneous neointima or neointimal thin-cap fibroatheroma in lesions with PMI (73.3% vs. 33.3%, p=0.02). Multivariate analysis including clinical and lesion characteristics and procedural results showed CAS-AP as an independent predictor for occurrence of PMI (odds ratio:6.90, 95% CI:1.68-28.41, p=0.008). Conclusions: In ISR lesions with SAP patients, the assessment of neointimal tissue characteristics by using CAS and OCT images may be useful for the prediction of occurrence of PMI.