Low-renin (volume dependent) mild-hypertensive patients have impaired flow-mediated and glyceryl-trinitrate stimulated vascular reactivity

Background Low-renin (volume-dependent) hypertension represents 25-30% of all cases of primary hypertension. Endothelial dysfunction and vascular remodeling are associated with hypertension but their relevance to volume-dependent hypertension (VDH) is not yet known. To evaluate this, flow-mediated dilation (FMD) of the brachial artery and the carotid intima-media thickness in the distal common carotid artery were measured and compared between renin-dependent mild-hypertensive patients (RDH) and controls. Method and Results The study group comprised 40 mild-hypertensive patients and 25 controls. Plasma renin activity (PRA), plasma aldosterone concentration, angiotensin U and nitrite/nitrate plasma levels were measured. According to PRA, subjects were classified as VDH ( 0.6 ng(.)ml(-1.)h(-1)). Vascular function was evaluated by FMD before and after reactive hyperemia (RH) and glyceryl-trinitrate (GTN) administration. FMD in response to RH and GTN in the VDH group when compared with RDH group was 10.2 +/- 2.8% vs 13.3 +/- 3.6% (p=0.01); and 16.0 +/- 3.5% vs 19.9 +/- 4.5% (p=0.01), respectively. Conclusion This study showed impaired FMD and reduced GTN response in mildly hypertensive patients with low-renin plasma levels.69111380138