In-stent coronary restenosis, but not the type of stent, is associated with impaired endothelial-dependent vasodilatation.

Background: Precise mechanisms leading to restenosis are not fully understood. The type of implanted stent and the intensity of atherogenic processes may affects the restenosis rate. Aim: To compare the long-term effects of the coronary stent implantation – paclitaxel-eluting stent (PES) or bare-metal stents (BMS) – on endothelial-dependent flow-mediated dilation (FMD), platelet-derived growth factor (PDGF) and asymmetric dimethylarginine (ADMA) serum levels and to assess the relationship between FMD, PDGF, ADMA and every-stage in-stent restenosis (eISR). Methods: The study population included 40 patients with coronary artery disease, who underwent elective percutaneous coronary intervention (PCI) of the left anterior descending artery (LAD) with stent implantation (PES – 21 patients; BMS – 19 patients). Follow-up examination was performed 12 months after PCI. Results: There were no differences between the PES and the BMS patients regarding FMD (PES: 11.8±7.8%, BMS: 10.5±9.2%), PDGF (PES: 5540±2209 pg/ml, BMS: 4923±2924 pg/ml) and ADMA (PES: 0.474±0.04 µmol/l, BMS: 0.456±0.03 µmol/l) serum levels. The follow-up angiography was performed when clinically indicated in 25 patients: in 15 patients with PES and 10 patients with BMS implanted. The eISR was found in 12 subjects: in 7 (47%) with PES and in 5 (50%) with BMS (NS). In all patients with eISR, the FMD values were significantly lower (6.1±3.5%, p=0.003) compared to the patients without eISR (14.3±7.8%). FMD was the only independent risk factor for eISR (OR=0.631, 95% CI 0.412-0.942, p=0.0003). The cut-off point for FMD Ł8.4% as a parameter predicting eISR was established (p=0.0001, sensitivity: 83.3%, specificity: 92.3%, PPV: 90.9%, NPV: 85.7%). Conclusions: The type of stent implanted into LAD does not affect the FMD, PDGF and ADMA serum levels assessed one-year after a PCI procedure. The occurrence of an early in-stent restenosis is associated with impaired FMD at the time of one-year follow-up.