Ex vivo repair of renal artery aneurysm associated with surgical treatment of abdominal aortic aneurysm

INTRODUCTION Renal artery aneurysms is relatively uncommon with reported incidence ranges from 0.3% to 1%. However, considering all visceral artery aneurysms the percentage of renal artery aneurysms is relatively high between 15-25%. The distal forms of renal artery aneurysms sometimes require "ex vivo" reconstruction and kidney autotransplantation. CASE REPORT A 75-year-old male presented with the right abdominal and back pain. He suffered from a long history of arterial hypertension and chronic renal failure over the last few months (urea blood = 19.8 mmol/l; creatinine = 198 mmol/l). Duplex ultrasonography showed abdominal aortic aneurysm. Subsequent translumbarangiography revealed juxtarenal abdominal aortic aneurysm associated with distal right renal artery aneurysm. The operation was performed under combined thoracic epidural analgesia and general anesthesia using transperitoneal approach. After the laparotomy, the ascending colon was mobilized and reflected medially followed by Kocher maneuver. The result was visualization of the anterior aspect of the right kidney, the collecting system, ureter as well as the right renal vein and artery with large saccular aneurysm located distally. After mobilization of the renal vessels and careful dissection of the ureter, the kidney was explanted. The operation was continued by two surgical teams. The first team performed abdominal aortic aneurysm resection and reconstruction with bifurcated Dacron graft. The second team performed ex vivo reparation of renal artery aneurysm. All time during the explantation, the kidney was perfused by Collins' solution. The saccular right renal artery aneurysm 4 cm in diameter was located at the kidney hilus at the first bifurcation. Three branches originated from the aneurysm. The aneurysm was resected completely. The longest and widest of three branches arising from the aneurysmal sac was end-to-end anastomized with 6 mm PTFE graft. After this intervention, one of shorter arteries was implanted into the long artery, and another one into PTFE graft. After 30 minutes of explanation, autotransplantation of the kidney into the right iliac fossa was performed. The right renal vein was implanted into the inferior vein cava, and PTFE graft into the right limb of Dacron graft. Immediately following the completion of both anastomoses, large volume of urine was evident. Finally, ureteneocystostomy was performed with previous insertion of double "J" catheter. In the immediate postoperative period, renal function was restored to normal, while postoperative angiography revealed all patent grafts. DISCUSSION The most common causes of renal artery aneurysms are arteriosclerosis, as in our case, and fibro-muscular dysplasia. Very often, renal artery aneurysms are asymptomatic and discovered only during angiography in patients with aneurysmal and occlusive aortic disease. Other cases include: arterial hypertension, groin pain and acute or chronic renal failure. Due to relatively small number of evaluated cases, the risk of aneurysmal rupture is not known. According to some authors, the overall rupture rate of renal artery aneurysm is 5%, however, the rupture risk becomes higher in young pregnant woman. Several standard surgical procedures are available for the repair of renal artery aneurysms. These include saphenous vein angioplasty, bypass grafting, as well as ex vivo reconstruction with reimplantation or autotransplantation. Furthermore, interventional embolization therapy, as well as endovascular treatment with ePTFE covered stent, or autologous vein-coverage stent graft, have been also reported to be successful. CONCLUSION The major indications for surgical treatment of renal artery aneurysms are to eliminate the source of thromboembolism which leads to fixed renal hypertension and kidney failure, as well as prevention of aneurysmal rupture.