Detrimental effects of a bout of physical exercise on circulating endogenous inhibitors of endothelial function in patients with coronary artery disease

BackgroundA bout of intense physical activity has been shown to transiently impair endothelial function; however, the underlying mechanisms are unclear.AimThe purpose of the review was to assess the impact of a bout of physical exercise induced by exercise stress echocardiography, on blood concentration of the endogenous inhibitors of nitric oxide synthase, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA), in patients with atherosclerosis.MethodsOverall, 83 study participants were enrolled, 25 coronary artery disease (CAD) patients, 20 age and sex-matched asymptomatic study participants with at least one risk factor for CAD, and 38 healthy controls.ResultsPatients with CAD developed symptoms and/or left ventricular wall motion abnormalities during exercise; no changes were seen in study participants with risk factors, or in healthy controls. At baseline, in CAD patients and in study participants with risk factors, both ADMA and SDMA were higher than healthy controls (P<0.001). However, a further large increase occurred during exercise stress echocardiography in both groups, regardless of development of symptoms (P<0.001).ConclusionBasal concentrations of ADMA and SDMA are high in CAD patients and in study participants with risk factors, consistent with impaired nitric oxide synthase activity in atherosclerosis. Large increase of these endogenous inhibitors of nitric oxide during intense exercise provide support to the hypothesis that in patients with atherosclerosis endothelial function may further deteriorate as a consequence of a bout of physical activity.