Asymmetric dimethylarginine and coronary collateral vessel development.

INTRODUCTION: Nitric oxide (NO) plays a major role in collateral vessel development. Asymmetric dimethylarginine (ADMA) that is an endogenous inhibitor of NO synthesis may impair the effective coronary collateral vessel development. The aim of this study was to evaluate the relationship between plasma ADMA level and coronary collateral vessel development.

METHODS: The patients with a greater than or equal to 95% obstruction in at least one epicardial coronary artery were included in the study. Degree of coronary collateral development was determined according to Rentrop method. Patients with grade 2-3 collateral development were regarded as good collateral group and formed group I. The patients with grade 0-1 collateral development were regarded as poor collateral group and were included in group II. Group III that had been formed as a control group included the patients with a normal coronary angiogram. We compared the plasma ADMA, symmetric dimethylarginine, L-arginine/ADMA ratio among three groups.

RESULTS: Seventy-four patients have been included in the study. Patients with good collateral development had lower plasma ADMA level in comparison with patients with poor collateral development (0.41+/-0.25 micromol/l vs. 0.70+/-0.23 micromol/l, P=0.001) and had similar plasma ADMA levels with the patients who have normal coronary arteries. When we compared L-arginine/ADMA ratio between good and poor collateral groups, we found that the patients with higher L-arginine/ADMA ratio have significantly better collateral development (270.8+/-168.0 vs. 120.9+/-92.1, P<0.001). In the analyses comparing Rentrop score with ADMA level and L-arginine/ADMA ratio, there were significant correlations (r=-0.444, P=0.008 and r=0.553, P=0.001, respectively). In multivariate analysis, ADMA level (odds ratio, 0.009; 95% confidence interval, 0.000-0.466, P=0.020) and L-arginine/ADMA ratio (odds ratio, 1.010; 95% confidence interval, 1.001-1.020, P=0.032) were independent predictors of collateral development.

CONCLUSION: Increased plasma ADMA levels are related with poor coronary collateral development. ADMA may be responsible for the difference in coronary collateral vessel development among different patients with coronary artery disease. NO inhibitors that have a determinative relation with endothelial cell functions may be integral prerequisite in all steps of collateral development.