DIgital intravenous subtraction angiography for investigating renovascular hypertension: comparison with hypertensive urography.

We used digital intravenous subtraction angiography (DSA) to evaluate 105 patients with suspected renovascular hypertension. Unilateral renal artery stenoses were identified in 14 patients, two of whom had previously had contralateral nephrectomy. In addition, one of three renal transplant recipients was found to have stenosis of the nutrient artery. Bilateral renal artery stenosis was demonstrated by DSA in three patients. Of the 88 patients who had concomitant minute sequence (hypertensive) urography (HIVP) delayed excretion suggested a renal artery lesion in only 8 patients. In the group of 88 patients, HIVP was able to detect renal artery stenosis in only 50% (eight of the 16) of patients whose stenosis was detected by DSA. When the patients with a single kidney are excluded, HIVP showed 62% (eight of 13) of the lesions detected by DSA. There were no significant complications in the patients examined by either modality. DSA has replaced HIVP as the screening examination for renovascular causes of hypertension in our institution.