The aim of this study is to analyze the autonomic nervous activity in patients with WED compared to healthy volunteers controls. The investigators will measure primarily the cardiac sympathetic activity by the 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy and secondarily the sympathetic nerve activity by the microneurography, the plasmatic pro inflammatory biomarkers and urinary catecholamine levels and the circadian variation of blood pressure and heart rate as assessed by the 24-hour ambulatory blood pressure monitoring.