Association of serum uric acid level and coronary blood flow.
Slow coronary flow (SCF) has long since been identified and endothelial dysfunction and atherosclerosis of the epicardial coronary arteries and microvasculature are reported to be associated with SCF. Serum uric acid is an independent biochemical marker of atherosclerosis, oxidative stress and endothelial dysfunction. Consequently, we aimed to investigate the association between coronary blood flow and serum uric acid level by means of thrombolysis in myocardial infarction frame count (TFC) and other laboratory parameters, in patients with SCF compared with control participants. Sixty-four patients with SCF and 369 control participants with normal coronary flow were studied after quantifying coronary blood flow according to TFC. Serum uric acid levels were determined using commercially available assay kits. The association between TFC and serum uric acid level and other clinical and laboratory parameters were evaluated. Statistically significant differences were present between SCF and control groups with respect to serum uric acid, and hemoglobin levels, heart rate, cigarette smoking and sex (P<0.05 for all). The mean TFC was significantly correlated with serum uric acid, urea, creatinine, high-density lipoprotein-cholesterol and hemoglobin levels, platelet count, male gender, cigarette smoking, heart rate and systolic blood pressure (P<0.05 for all). Serum uric acid level (chi(2)=22.86, beta=0.54, P<0.001), heart rate (chi(2)=7.42, beta=-0.034, P=0.032) and cigarette smoking (chi(2)=12.343, beta=0.969, P=0.025) were independent predictors of SCF, whereas serum uric acid level was the only independent predictor of the mean TFC (beta=0.298, P<0.001). These findings have shown that serum uric acid level is significantly associated with coronary blood flow and that elevated uric acid might be an independent predictor for the presence of SCF.