Value of MR angiography before percutaneous transluminal renal artery angioplasty and stent placement

PURPOSE: To determine the benefit of preprocedural three-dimensional gadolinium (Gd)-enhanced magnetic resonance (MR) angiography before percutaneous transluminal renal artery angioplasty and stent placement (PTRA/S) in terms of procedural success, iodinated contrast material load, and procedure duration. MATERIALS AND METHODS: Over an 18-month period, 39 patients underwent attempted percutaneous renal angioplasty with or without stent placement. A total of 48 renal arteries were treated (40 cases of atherosclerosis, one of stent restenosis, five of fibromuscular dysplasia, and two of transplant stenosis). Preprocedural Gd-enhanced MR angiography was available in 16 procedures (41%). Procedural outcome, complications, iodinated contrast material load, number of diagnostic angiographic runs, and total procedure duration were each compared between two subgroups: patients who had preprocedural Gd-enhanced MR angiography ("prior MR angiography group") and those who did not ("no MR angiography" group). RESULTS: All procedures were technically successful. The two groups were equivalent in terms of age and disease pattern. However, technical complexity of the procedure was judged to be high in five of 16 procedures in the prior MR angiography group compared to three of 23 procedures in the no MR angiography group (P = .16). Bilateral or dual interventions were performed in six of 16 procedures in the prior MR angiography group compared to three of 23 in the no MR angiography group (P = .075). Iodinated contrast material load was significantly lower in the prior MR angiography group than in the no MR angiography group (68.7 mL +/- 28.4 vs 119.1 mL +/- 49.2 mL; P < .0008). The number of diagnostic angiographic runs before interventions were also significantly lower in the prior MR angiography group (1.2 +/- 0.4 vs 2.6 +/- 0.7, P < .0001). Overall procedure duration was comparable between the two groups (91.9 +/- 47.8 vs 112.2 +/- 49.4; P = .2). CONCLUSION: Preprocedural planning with use of Gd-enhanced MR angiography significantly reduces the iodinated contrast material requirement during percutaneous renal artery interventions. It can also significantly shorten procedure duration.