Is plasma asymmetric dimethylarginine level a novel marker for stent restenosis?

Nowadays stents are widely used for the treatment of coronary artery disease. During the wide spread usage of coronary stenting, stent restenosis was found to be the major problem related with this intervention. Neointimal hyperplasia composed of vascular smooth muscle cells and the matrix is the mainstay of stent restenosis. Nitric oxide secreted by intact endothelium inhibits vascular smooth muscle cell proliferation and prevents neointimal hyperplasia. Asymmetric dimethylarginine (ADMA) is a potent competitive inhibitor of nitric oxide synthase (NOS). The aim of this study was to examine whether plasma ADMA level is a predictor of stent restenosis or not. We recruited 91 patients with a history of coronary stenting who underwent coronary angiography due to various reasons. Subjects were eligible if they had no history of chronic kidney or liver disease, no history of cerebrovascular accident in the past year and were free of uncontrolled hypertension, clinical hyperthyroidism, erectile dysfunction, pulmonary hypertension and uncontrolled diabetes mellitus. Asymmetric dimethylarginine concentrations were measured by high performance liquid chromatography (HPLC). The mean age of the patients was 58.9 ± 8.7 years and 72 (79.1 %) of them were male. We assessed 144 stents of 91 patients with coronary angiography. Angiographic restenosis was found in 35 patients (38.5 %) and 46 of 144 stents (31.9 %). When clinical characteristics and laboratory findings considered, stenting history due to acute coronary syndrome (p = 0.029), plasma ADMA concentrations (p = 0.001), C-reactive protein concentrations (p = 0.01) and white blood cell count (p = 0.044) were higher and left ventricular ejection fraction (p = 0.023) lower in patients with restenosis. Plasma ADMA concentration (β = 0.281; p = 0.012) and clinical setting before stenting (β = 0.233; p = 0.037) were found to be the independent predictors of restenosis in multiple linear regression analysis. When we consider the properties of stent and the implantation procedure, we found the stent diameter (β = – 0.302; p = 0.001) and length (β = 0.238; p = 0.015) as the independent predictors of restenosis. In conclusion, plasma ADMA level is found to be an independent predictor of restenosis.