Background: Given that the endogenous nitric oxide synthase inhibitor, asymmetric dimethylarginine, can decrease nitric oxide bioavailability and lead to atherosclerosis, its concentration can be a good predictor for coronary artery disease. In this study, we investigated the relationship of plasma asymmetric dimethylarginine concentration with lesion distribution and severity at coronary artery angiography.
Method: Ninety-eight patients with stable angina were enrolled prospectively. We divided the patients into two groups. Group I (n=37) included the patients with normal coronary arteries. All the other patients were included in group II (n=61). We calculated coronary atherosclerotic score and coronary vessel score. Plasma asymmetric dimethylarginine, L-arginine and symmetric dimethylarginine concentrations were measured and L-arginine/asymmetric dimethylarginine ratio was calculated.
Results: Plasma L-arginine and symmetric dimethylarginine concentrations did not differ in the two groups. The plasma asymmetric dimethylarginine level, however, was higher in group II patients than in group I patients (0.43+/-0.26 vs. 0.59+/-0.28 micromol/l, P=0.004) and L-arginine/asymmetric dimethylarginine ratio was lower in group II patients than in group I patients (262.0+/-186.4 vs. 176.6+/-139.8, P=0.019). Asymmetric dimethylarginine was positively correlated with the coronary atherosclerotic score (rs=0.273, P=0.006). Moreover, asymmetric dimethylarginine was an important predictor of angiographically defined coronary artery disease (odds ratio=14.42, P=0.004).
Conclusion: Our findings support the hypothesis that the plasma asymmetric dimethylarginine concentration may be a good indicator of predicting coronary artery disease.