Captopril-stimulated renin in the diagnosis of restenosis after percutaneous transluminal renal angioplasty.

Recurrence of hypertension is reported in a considerable percentage of renovascular hypertensive patients treated by percutaneous transluminal angioplasty (PTRA); among the possible mechanisms for these failures, restenosis of the renal artery is the only correctable one. Since captopril stimulates renin secretion to a greater extent in renovascular than in essential hypertensive patients, we determined if it could be used to unmask significant restenosis in the patients with hypertension recurring after PTRA. Follow-up study was performed in 28 patients treated with PTRA. We found that captopril caused a greater increase in peripheral plasma renin activity in 8 of 8 cases who had recurrence of hypertension and restenosis than in 13 of 15 of the patients who did not. We suggest that the determination of captopril-stimulated renin may provide a useful, simple and economical tool for the detection of restenosis after PTRA.