FMD is an idiopathic, segmental, non-atherosclerotic non-inflammatory arterial disease of unknown origin which occurs mostly in middle-aged women and affects medium-sized arteries (renal and carotid arteries in particular). The objective of the study was to identify new hemodynamic and biological biomarkers of the pathology. We investigated i) the flow-mediated dilation (FD) and endothelium-independent dilation (ED) of the brachial artery (BA); ii) c-MVs from different vascular cell origins.Design and method:
We conducted a cross sectional study with 50 patients with multifocal FMD, 50 essential hypertensive (EH) patients matched for age, sex, ethnicity and BP and 50 healthy subjects (HS) matched for age, sex and ethnicity. Exclusion criteria were: tobacco consumption, hypercholesterolemia, diabetes, aspirin or statin treatment. We measured blind to the phenotype: 1) changes in BA diameter after release of hand ischemia (FD) and glyceryl trinitrate (ED) by high-resolution radiofrequency-based echotracking system; and 2) endothelial and smooth-cell derived MVs plasma concentrations by flow cytometry analysis of human platelet free plasma.Results:
FMD, EH and HS were well matched. FMD and EH had significantly higher SBP than HS despite antihypertensive treatments. Circulating levels of total MVs (annexinV + MVs), endothelial MVs (CD144 + MVs, CD62E + MVs and CD31 + CD41-MVs), CD11a + MVs and smooth muscle derived MVs (SMA (smooth muscle actin) + MVs) displayed large between-subject variability within each group and did not significantly differ between groups. FD or ED changes in BA diameter did not significantly differ between groups.Conclusions:
In conclusion, we could not identify specific changes in c-MVs levels of endothelial or smooth muscle origin in patients with FMD when compared with age-, sex-, and ethnicity-matched patients with EH or HS. This result is consistent with the similar acute vasodilatory responses to flow and glyceryl trinitrate observed in FMD patients compared to EH and HS. Taken all together, these results demonstrate that endothelial function is not affected in patients with FMD.