Stent placement in patients with coronary heart disease decreases plasma levels of the endogenous nitric oxide synthase inhibitor ADMA

The concentration of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is increased in patients with coronary heart disease (CHD). The potential effect of percutaneous coronary intervention (PCI) with stent placement on ADMA plasma level in CHD patients has not yet been investigated. Concentrations of ADMA, L-arginine, symmetric dimethylarginine (SDMA), and L-ornithine were measured in the plasma of 30 CHD patients 24 h before, and 1 h, 5 days, and 30 days following PCI with bare-metal stent or drug-eluting stent placement (stent group) and in the plasma of 20 patients without CHD who underwent angiography alone (control group). A repeated measures ANOVA revealed the significant time by group interaction for ADMA (F=12.8, p<0.0001), SDMA (F=5.5, p=0.013), L-ornithine (F=12.5, p<0.0001), L-aginine (F=4.7, p=0.013) and L-arginine/ADMA ratio (F=7.1, p<0.001). Post-hoc ANOVAs showed that this interaction was due to the fact that control patients without stent placement responded to the coronary angiography with a significant increase in ADMA (F=4.4, p=0.009), SDMA (F=4.7, p=0.007) and L-ornithine (F=28.3, p<0.0001) levels, whereas the stent implantation independent of the stent type used significantly reduced the cardiovascular risk factor ADMA (F=10.8, p<0.0001). Thus, the current study demonstrates that in patients with CHD, PCI stent placement markedly decreases the plasma level of cardiovascular risk factor ADMA. Coronary angiography alone results in an increase of ADMA. We conclude that the stent effect on ADMA level cannot be explained by unspecific effects of the coronary angiography and is independent of the stent type used.