Relationship Between the Flow-Mediated Dilatation of the Human Brachial Artery and Blood Biomarkers Related to the Endothelial Function in Cardiovascular Diseases

Objective: Endothelial dysfunction plays an important role in the development of heart diseases. Although several markers have been examined, a definitive biomarker for monitoring endothelial function has not yet been established. The flow-mediated dilatation (FMD) of the brachial artery enables non-invasive assessment of endothelial function. This study investigated plasma levels of nitric oxide (NO), asymmetric dimethylarginine (ADMA), total antioxidant capacity (TAC), and hydrogen sulfide (H2S) as biomarkers of endothelial function. This study aimed to investigate any correlation between FMD and these blood biomarkers in patients with diabetes mellitus (DM), prediabetes (preDM), coronary artery disease (CAD), and valvular heart disease (VD). Materials and Methods: Prospective evaluation was made within five groups of patients with preDM, DM, CAD, VD, and healthy controls. The FMD of the brachial artery was examined using Doppler imaging, and biomarker levels in plasma were measured by spectrophotometry. Results: The FMD of the VD group was significantly higher than that of DM and CAD groups. Plasma NO levels of CAD and VD groups were significantly lower than those of the control group. ADMA levels were lower in the CAD group. TAC and H2S levels were comparable in all groups. The FMD of the brachial artery was negatively correlated with plasma NO and cholesterol levels in all groups. Conclusion: These results suggested that the correlation of FMD with blood biomarkers related to endothelial function was altered in cardiovascular diseases and would be affected by the patient's clinical state and treatment.