Study On Optical Coherence Tomography In Restenosis Of Drug - Eluting Stent

Background:In-stent restenosis (ISR) is generally considered to be a benign and stable process, However, more and more patients with ISR have presented with acute coronary syndromes and ISR has been suggested to be one of the important causes of DES failure. Morphologic characteristics of in-stent restenosis after drug-eluting stent (DES) is still unclear.Methods:Optical coherence tomographic data were analyzed in20patients(5with stable angina,15with acute coronary syndrome) who presented in-stent restenosis at angiographic follow-up after DES implantation. In-stent restenosis was defined as a>50%diameter stenosis within stent or stent-edge by quantitative coronary angiography (QCA) assessment.Results:The average angiographic follow-up duration was25.9±10.3months. A total of20lesions in20patients were analyzed by QCA and OCT, among which there were19lesions (95.0%) showed OCT-defined lipid-rich intima and16lesions (80.0%) had at least1OCT-defined in-stent thin-cap fibroatheroma (TCFA).Totally,13lesions (65.0%) had at least1OCT-defined in-stent neointima rupture and14lesions (70.0%) had at least1OCT-defined in-stent thrombus. TCFA-containing neointima was more frequently observed in DESs more than12months after implantation, compared with those<12months(100%versus50%, P＝0.014). And Patients with diabetes showed higher incidence of TCFA-containing neointima than those without diabetes (100%versus60.0%, P=0.043). Compared with patients with stable angina patients with acute coronary syndrome had a higher incidence of TCFA (93.3%versus40.0%, P=0.032) and a thinner fibrous cap (62.9±23.4versus131±64.4μm, P＝0.006).Conclusions:Neoatherosclerosis may be the major mechanism of DES in-stent restenosis, as closely associated with in-stent thrombus and intimal rupture, especially≥12months after stent implantation and in patients with diabetes and acute coronary syndrome.