The effect of sodium restriction in renovascular hypertension

Six patients with angiographically proven renal artery stenosis were given a low salt diet, consisting of 10 mEq sodium per day for 4-6 days. Five patients showed a remarkable decrease in blood pressure (BP), from 169 +/- 12/107 +/- 4 to 131 +/- 12/84 +/- 5 mmHg, despite a rise in renin level. The decrease in BP was paralleled by a decrease in urinary sodium excretion. Restoration of the regular diet caused immediate elevation of blood pressure. We conclude that severe sodium restriction can reduce blood pressure in patients with renovascular hypertension.