Abstract 2539: The Association Between Systemic Inflammation, Statin Therapy, and Saphenous Vein Endothelial Function in Patients Undergoing Coronary Artery Bypass Surgery
Systemic inflammation and endothelial dysfunction (ED) are independent predictors of future cardiovascular events. Statins, used to treat high cholesterol levels, improve ED, and reduce systemic inflammation. We investigated the association between C-reactive protein (CRP - a marker of systemic inflammation) and saphenous vein (SV) endothelial function in patients optimally treated with statins undergoing coronary artery bypass surgery. 76 patients with optimal LDL cholesterol levels (<1.6 (SD 0.05)mmol/l) secondary to regular treatment with a minimum of simvastatin 40 mg were recruited. 26% of patients had CRP levels in the “high risk range” (>3 mg/L) despite statin therapy. Acetylcholine (ACh) induced relaxation was assessed ex vivo in harvested SV rings. There was a negative linear correlation between ACh- induced SV relaxation and CRP (r=-0.30, p=0.02), and waist circumference (r=-0.21, p=0.03). In a multivariate regression model CRP (p=0.02) was the only independent predictor of ACh induced venous relaxation (Panel A). In turn correlates of CRP were assessed. There was a correlation between CRP and angiographic estimates of coronary atherosclerotic burden (A-burden r=0.46, p<0.0001) , BMI ( r=0.26, p=0.03), glucose (r=0.31, p=0.01) and waist circumference (r=0.29, p=0.01). Using multivariate analysis coronary atherosclerotic burden (p<0.0001) was the only independent preidictor of CRP (Panel B). In patients with coronary artery disease, treated with statins to achieve optimal LDL cholesterol levels, a sizeable proportion had CRP levels within the “high risk” range. CRP was the only independent predictor of impaired saphenous vein endothelial function.