Renovascular hypertension: the small kidney updated.

We report the results of treatment in 57 patients with renovascular hypertension associated with one poorly perfused, small kidney with less than 25 per cent of total 131I-hippurate uptake shown by renography. Arteriography in 29 patients demonstrated occlusion of the artery of the small kidney, and in 28 there was stenosis. In addition, 25 patients had stenosis of the artery supplying the larger contralateral kidney. Stenosis of the arteries of the contralateral kidneys was dilated by percutaneous transluminal arterioplasty in all but one of the 25 patients with bilateral disease of the artery, stenosis of the small kidney could be dilated successfully by percutaneous transluminal arterioplasty in 22 of the 28 patients, and cure or improvement of blood pressure was achieved in 12 of them. Percutaneous transluminal arterioplasty of occluded arteries was generally unsuccessful. In 17 patients with unilateral disease not manageable by percutaneous transluminal arterioplasty, nephrectomy of the small kidney improved blood pressure control without significant deterioration of renal function. Renal function improved in 10 patients with bilateral lesions treated by nephrectomy of the small kidney in combination with contralateral percutaneous transluminal arterioplasty. Histological examination of excised kidneys showed large infarcts or several cholesterol emboli whether percutaneous transluminal arterioplasty had been attempted or not. After observation periods ranging from two to 79 months, 48 patients were normotensive (21 without and 27 with medication) and nine patients were still hypertensive even with medication. This study showed that by using percutaneous transluminal arterioplasty initially if possible, supplemented with nephrectomy and/or medication, normotension without loss of renal function or immediate serious complications could be obtained in the majority of these severely hypertensive patients.