Surgical correction of renovascular hypertension: dissociation between post-operative changes in plasma renin and blood pressure.

Conventionally used criteria for predicting the blood pressure response to surgery in renovascular hypertensive disease rely on the demonstration of renin dependency. To assess the validity of this, we have related post-operative changes in plasma renin to the efficacy of surgical treatment of renovascular hypertension. We report nine hypertensive patients with unilateral renal disease and raised peripheral plasma renin activity (PRA), who were studied before and after either nephrectomy or renal artery stenosis bypass. In four patients blood pressure fell to normal levels, and has remained normal without treatment for periods varing from one to four years. In only one of these patients did renal vein renin studies indicate hypersecretion of renin on the operated side with contralateral suppression. Of the remaining five patients, three showed partial reduction of diastolic blood pressure and in two blood pressure was unchanged, although it was more easily controlled with antihypertensive medication. In all patients studied, peripheral venous plasma renin activity fell significantly after surgery, becoming normal in seven patients: in one of these blood pressure was unchanged, and it remained significantly elevated in two. Thus, correction of renin hypersecretion is not necessarily associated with restoration of blood pressure to normal. Tests for surgical correctability of renal hypertension which attribute a central role to renin hypersecretion may therefore yield misleading results.