 A randomized clinical trial comparing sequential nephron blockage SNB with dual blockade of the renin-angiotensin system RAAS plus bisoprolol DBB in the treatment of resistant arterial hypertension RH was designed to investigate the importance of the SNB and the contribution of its volume component versus DBB and the importance of the serum renin in maintaining BP levels. This randomized trial with two treatment arms could help tailor therapy by identifying a more effective choice to control hypertension whether by acting on the control of volume or sodium balance, or by acting on the effects of the RAAS on the kidney. 