Angiotensin converting enzyme inhibitor-induced renal dysfunction in atherosclerotic renovascular disease

Angiotensin converting enzyme inhibitor-induced renal dysfunction in atherosclerotic renovascular disease. Ischemic nephropathy due to bilateral renovascular disease (RVD) is increasingly recognized as cause of end-stage renal failure in the elderly, but a reliable non-invasive method of detection is not available. Angiotensin converting enzyme inhibition (ACEi) may impair renal function in such patients, but a prospective study of its diagnostic validity has not been undertaken. We studied the effects of controlled exposure to ACEi on plasma creatinine in 108 patients at risk for severe bilateral atherosclerotic RVD, and compared the findings with subsequent angiography. ACEi was given for two weeks, or, to avoid acute renal failure, for four days if plasma creatinine had increased by 20% or more. If after two weeks of ACEi plasma creatinine had not increased by ≥ 20%, while blood pressure was still elevated, plasma creatinine was remeasured after blood pressure control by addition of diuretics. The severity of RVD was scored by the stenosis grade of the best perfused kidney. Fifty-two patients had severe bilateral RVD, defined as ≥ 50% stenosis to both kidneys ( N = 23) or a solitary functioning kidney ( N = 29). Of the others, 21 had less severe bilateral RVD, 20 unilateral RVD, and 15 no apparent RVD. Basal plasma creatinine was higher in severe bilateral RVD (median 170 μmol/liter, range 85 to 654 μmol/liter) than in the others (122 μmol/liter, 62 to 675 μmol/liter; P r = 0.53, P