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Gadolinium as a nonnephrotoxic contrast agent for catheter-based arteriographic evaluation of renal arteries in patients with azotemia.

OBJECTIVE
This study was undertaken to determine the effect of gadolinium arteriography on renal function and its diagnostic accuracy in patients with azotemia with suspected renovascular disease.


METHODS
Catheter-based digital subtraction arteriographic studies with gadolinium as the contrast agent were performed on 25 occasions in 21 consecutive patients with azotemia to evaluate renal arterial circulation. Gadolinium (gadodiamide, 287 mg/mL) was the only contrast used in these studies. Quantities of gadolinium administered ranged from 40 to 264 mL (mean +/- standard deviation, 124 +/- 74 mL). Serial determinations of renal function were performed in all patients. Arteriography was undertaken 20 times after prior renal revascularizations: seven times as a routine postoperative follow-up study, nine for increasing azotemia, three for worsening hypertension, and once for evaluation of a known renal artery stenosis in patient with an abdominal aortic aneurysm. Three additional arteriograms were performed as part of an evaluation for suspected renovascular hypertension. The two remaining arteriograms were performed in patients with known aortic aneurysms in whom renal artery stenosis was suspected.


RESULTS
No adverse changes in renal function followed gadolinium arteriography. Prearteriography serum creatinine values ranged from 1.6 to 9.1 mg/dL (3.0 +/- 1.4 mg/dL), compared with postangiography values that ranged from 1.2 to 8.4 mg/dL (2.9 +/- 1.3 mg/dL). Comparable blood urea nitrogen values ranged from 23 to 71 mg/dL (40.1 +/- 13.5 mg/dL) before arteriography and from 21 to 68 mg/dL (36.5 +/- 13.3 mg/dL) after arteriography. All 38 renal arteries evaluated were adequately imaged. First-order and second-order branchings were well visualized on selective renal studies. Twenty-one renal arteries showed no abnormalities, including six of seven reconstructed arteries subjected to early postoperative evaluation. Twelve renal arteries manifested significant disease, including seven with stenoses and five that had become occluded. Among five additional renal arteries studied, two exhibited obstructing thrombus, two had dissections, and one had a kinked aortorenal bypass graft.


CONCLUSION
Catheter-based arteriography in patients with azotemia with gadolinium as a contrast agent is a safe and effective means to evaluate the renal arterial circulation. The preferential use of gadolinium in lieu of nephrotoxic iodinated contrast agents for catheter-based arteriography in patients with azotemia is supported by this experience.