Autologous Arterial Patch Closure of a Mycotic, Inter-renal Aortic Aneurysm
Article Outline
A mycotic aortic aneurysm (MAA) located at the level of the renal artery is a rare vascular condition that is difficult to treat. For a patient with MAA, we performed an arterial patch closure of the aortic wall defect using an autologous hypogastric artery. We present the treatment result after a 20 months's follow-up.
Keywords: Abdominal aortic aneurysm, Mycotic aneurysm, Treatment, Salmonella infection
Introduction
Mycotic aortic aneurysms (MAA) caused by Salmonella species is still associated with high morbidity and mortality rates after surgical treatment especially when it develops at the level of splanchnic arteries.1 In situ aortic reconstruction with prosthetic graft carries potential risk of graft infection. In situ aortic reconstruction can be performed using autologous blood vessel2 but it is difficult to find a suitable vessel for aortic reconstruction.
Considering the anatomic characteristic of saccular shape in MAA, we performed a patch closure of the aneurysmal neck using an autologous arterial patch.
Report
A 71-year-old Korean male patient presented with back pain, chills and fever for 2-day duration. His medical history included type II diabetes mellitus, hypertension and silent gall bladder stones, but he denied any evidences of Behcet's disease or cardiac disease. The blood culture performed at the initial presentation revealed serotype B Salmonella. The abdominal CT angiography (Fig. 1) revealed a saccular shaped aneurysm located at the posterior wall of the abdominal aorta between the renal arteries. The aneurysm was 28
×18mm in size. After 4 weeks of systemic antibiotic therapy with ciprofloxacin, we performed an elective surgical repair of the MAA through the transperitoneal approach.
Fig. 1
Preoperative abdominal CT angiography. Note the saccular shaped aneurysm located at the posterior wall of the abdominal aorta between the renal arteries.
After opening the peritoneum, a proximal segment of the right hypogastric artery (about 4cm in length) was harvested with its distal branches perserved. After exposing the aortic segment around the renal artery, 3000IU of Heparin and 100cc of 12.5 % mannitol solution were infused intravenously before clamping the renal arteries, supra- and infra-renal aorta. By mobilizing the overlying left renal vein cephalad and caudad, a longitudinal aortotomy was performed at the anterior wall of the inter-renal aorta to expose the aortic defect at the posterior wall of the aorta. The excised hypogastric artery was opened longitudinally and tailored to fit the aortic defect. After copious irrigation of the aneurysmal sac, the aortic defect at the posterior wall was closed with the arterial patch using 4-0 polyproplylene continuous sutures.
Renal artery clamping time was 16 minutes. After antibiotic solution irrigation, the aortotomy site was covered with the great omentum.
Cholecystectomy was performed on purpose to remove a potential source of Salmonella carrier. Bacterial culture of the thrombus from the aneurismal sac identified no growth of bacteria. Postoperatively ciprofloxacin was used for 10 days and the patient recovered without complication. Follow-up CT arteriography performed 20 months after surgery (Fig. 2) showed no recurrence of the aneurysm.
Fig. 2
Postoperative 20 month follow-up CT angiography.
Discussion
The management of infected aortic aneurysm is still major challenge in vascular surgery. In addition to systemic antibiotic therapy, various treatment options exist for patient with MAA including MAA resection with an extra-anatomic bypass and in situ aortic reconstruction using autologous blood vessel,2 a prosthetic graft,3 cryopreserved arterial allograft4 or even endovascular stent graft.5
Although some authors have reported good outcomes after an in situ aortic reconstruction with a prosthetic graft,3 the safety of this procedure is still under debate. Other authors proposed the use of an autologous femoral vein graft for an in situ aortic reconstruction with relative safety.2 However, it requires another skin incision for vein harvest and carries potential risk of leg compartment swelling. We believe that an autologous arterial patch has a higher strength than the femoral vein graft.
Cryopreserved arterial allograft for patients with an infected aorta also has problems of later development of degenerative changes that can lead to graft calcification, an aneurismal change or rupture.4
Considering the characteristic feature of saccular shape in MAA and to minimize the renal ischemic time, we performed an autologous arterial patch closure of the aneurismal neck. We found that the suprarenal aortic clamping time was acceptable with this procedure.
An endovascular aortic aneurysm repair (EVAR) is an alternative treatment for MAA. However, it cannot provide surgical debridement of the infected tissue. Forbes et al.5 reported aortoenteric fistula after EVAR in a patient with a salmonella-infected abdominal aortic aneurysm. Therefore further evaluation of the safety and long-term results will be needed before EVAR can be used in MAA.
We present a case of the successful surgical treatment of a MAA using an autologous arterial patch, which might be another treatment option for patients with a saccular shaped MAA.
References
- . Infected aortic aneurysms: clinical outcome and risk factor analysis. J Vasc Surg. 2004;40:30–35
- . Autogenous aortoiliac/femoral reconstruction from superficial femoral-popliteal veins: feasibility and durability. J Vasc Surg. 1997;25:255–266[discussion 67–70]
- . Surgical treatment of infected aneurysms and pseudoaneurysms of the thoracic and abdominal aorta. Am J Surg. 2005;189:150–154
- Abdominal aortic reconstruction in infected fields: early results of the United States cryopreserved aortic allograft registry. J Vasc Surg. 2002;35:847–852
- . Endovascular repair of Salmonella-infected abdominal aortic aneurysms: a word of caution. J Vasc Surg. 2006;44:198–200
PII: S1533-3167(07)00022-2
doi:10.1016/j.ejvsextra.2007.04.003
© 2007 European Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
