Abstract 14141: A Novel Endothelial Function Test in Predicting Late Coronary In-Stent Restenosis

Abstract

Introduction: Endothelial dysfunction is related with in-stent restenosis (ISR) of prior drug-eluting stents (DES) implanted more than 1 year ago (late ISR). EndoPAT is a novel non-invasive test quantifying endothelial function as reactive hyperemia peripheral arterial tonometry index (RHI). Hypothesis: EndoPAT is a potential predicting test for late ISR. Methods: We conducted a case control study on 186 patients with coronary DES implanted more than 1 year ago in a single medical center. Those who had contraindications to EndoPAT test, acute myocardial infarction, coronary artery bypass graft (CABG), chronic kidney disease (CKD) stage III and above, active infection and rheumatologic disease or acute decompensated heart failure were excluded. Patients were divided into ISR and non-ISR group based on coronary angiography. EndoPAT test was done at 24 to 48 hours prior to catherization. LnRHI is an index after natural log transformation of RHI. A receiver operative characteristic (ROC) curve analysis was used to determine the sensitivity and specificity of LnRHI for predicting late ISR. Results: ISR group had significantly more patients with history of ISR or triple-vessel disease, longer stent length and fewer totally occlusive lesions than non-ISR group. LnRHI was significantly lower in ISR group than in non-ISR group (0.66 vs 0.50, p<0.01). Patients with diffuse ISR had lower LnRHI than those with focal ISR (0.40 vs 0.55, p=0.03). Patients without ISR but undergoing revascularization had lower LnRHI than those with patent coronary arteries (0.56 vs 0.70, p=0.02). Endothelial function quantified by LnRHI was an independent risk factor for ISR (LnRHI/0.1, OR=0.79, 95% CI 0.64-0.97, p=0.03). The ROC curve analysis showed LnRHI of 0.44 had a sensitivity of 81.7% and specificity of 53.8% for predicting late ISR. Conclusions: Endothelial dysfunction measured by EndoPAT had a clinical potential for predicting the development of late ISR.