Factors affecting in-stent restenosis and the role of flow-mediated dilatation

Abstract

Objective: In-stent restenosis is a major problem concerning percutaneous coronary interventions. Brachial artery flow-mediated dilation, a non-invasive indicator of endothelial dysfunction, and its relationship with future cardiovascular events is well known. The aim of this study was to identify factors thought to have an effect on in-stent restenosis and to test the predictive value of flow-mediated dilatation. Method: 74 consecutive patients who were treated with bare-metal stents and recommended control coronary angiography during their follow-up were included into the study. Patients were categorized into 2 groups in the form of those having in-stent restenosis (n=35) and no in-stent restenosis (n=39). Clinical, biochemical, angiographic parameters and also flow-mediated dilatation was evaluated. Results: Flow-mediated dilatation was significantly impaired in patients with in-stent restenosis than in patients with no in-stent restenosis (5.1(4.8) % vs. 9.2(4.1) %, p<0.001). After multivariable analysis; flow-mediated dilatation (p=0.004), stent diameter (p=0.014), stent length (p=0.01), no use of statins (p=0.017) and absence of TIMI-3 flow (p=0.039) were found as independent predictors of in-stent restenosis. According to the receiver-operating characteristic curve analysis, optimal cut-off value of flow-mediated dilatation to predict in-stent restenosis was measured to be ≤6.8%, with 75.8% sensitivity and 78.8% specificity (Area under curve 0.764, 95% confidence interval 0.644-0.885). Conclusions: Our study suggested that flow-mediated dilatation may contribute to the identification of high-risk patients who will develop in-stent restenosis after percutaneous coronary interventions.