Impact of aortorenal morphology on renal artery stent procedures: significance of aortic tortuosity and renal artery derivation.

Purpose: To clarify the impact of aortorenal morphology on renal artery stenting procedures.

Methods: A retrospective study evaluated 142 consecutive renal artery stenting procedures performed for de novo atherosclerotic renal artery stenosis in 119 patients (62 men; mean age 72±9 years, range 41-93). All procedures were done via a transfemoral approach without distal protection. Aortorenal morphology was classified into 3 types based on the relationship between abdominal aortic tortuosity and renal artery derivation. Using a straight reference line centered on the most angulated point of the inner curve of the infrarenal abdominal aorta, type 1 referred to a renal artery ostium that was more than half of the aortic diameter distance from the reference line in the greater curvature and less than half in the lesser curvature. Type 2 referred to a renal artery ostium that was less than half of the aortic diameter distant from the reference line in the greater curvature and more than half in the lesser curvature. Type 3 referred to a renal artery ostium that was beyond the reference line in the greater curvature or more than one aortic diameter from the reference line in the lesser curvature. The technical success rate, procedure time, final engagement technique, shape of the guide catheter used, and any adverse events were analyzed.

Results: Type 1 aortorenal morphology was observed in 91 cases, type 2 in 30, and type 3 in 21. All cases were successfully treated; there were no technical complications, in-hospital cardiovascular events, or deaths. Procedure time differed significantly (p<0.001) among the 3 types (type 1: 19.6±5.6 minutes, type 2: 23.3±6.8 minutes, and type 3: 32.3±9.6 minutes; p<0.05 for type 1 vs. 2, p<0.001 for type 2 vs. 3, and p<0.001 for type 1 vs. 3). There were also significant differences among types in terms of engagement technique and guide catheter shape.

Conclusion: Aortorenal morphology was significantly associated with procedure time and the selection of engagement technique and guide catheter shape.