Surgical Management of Extraparenchymal Renal Artery Aneurysms

Abstract

Renal artery aneurysms are being encountered with increasing frequency owing to the more liberal use of sensitive diagnostic imaging. Despite numerous historical reports, some controversy exists regarding the clinical significance of small (<2.5 cm) renal artery aneurysms. At their institution the authors favor an aggressive approach in the management of extraparenchymal renal artery aneurysms. This study comprises their experience over the last 7 years. From 1989 to the present, 22 renal artery aneurysms were discovered at their institution. All patients were offered surgical repair, and three of the 22 refused surgery. Two of the patients who refused had asymptomatic aneurysms < 2 cm in size, and the other eventually expired from aortic dissection. The surgically treated patient population consisted of seven men and 12 women with a mean age of 56.9 years (range 11-79). Seven patients were asymptomatic, two presented with pain, eight were hypertensive, five had an associated abdominal aortic aneurysm, one had occlusive disease, and one patient had neurofibromatosis. The aneurysms had a mean size of 2.4 cm (range 1.5-4.0) and occurred at the main renal artery (seven patients), or at the hilar bifurcation (11 patients), or at a secondary bifurcation (one patient). All surgical repairs were performed via a retroperitoneal approach. Procedures included 11 arterioplasties, four polytetrafluoroethylene (PTFE) bypasses based on aortic replacement grafts, one renal artery reimplanted into the aortic replacement graft, two aortic based Goretex bypasses, and one interposition vein bypass. Operative mortality for these patients was 0%. No patient had worsening of renal function based on values preoperative and postoperative blood urea nitrogen/creatinine values. Four patients with preoperative hypertension and with saccular-type bifurcation aneurysms who underwent arterioplasty are now normotensive and require no antihypertensive medication. Mean follow-up for these patients is 1.5 years and duplex ultrasound revealed all reconstructed arteries or bypasses to be patent. These data suggest that extraparenchymal renal artery aneurysms can be safely repaired operatively with minimal morbidity and mortality rates.