Endovascular repair of an aorto-iliac aneurysm succeeded by kidney transplantation

Treatment of patients with aorto-iliac aneurysm associated with chronic renal failure (CRF) under hemodialysis is a challenge, due to increased morbimortality1,2. Several authors reviewed open aneurysm repair in association with kidney transplantation (RT) and proposed a staged approach with aorto-iliac disease being treated first3-5. Endovascular aneurysm repair (EVAR) has been replacing open repair in patients with a high surgical risk, with the advantages of less morbimortality and shorter operative time and hospital stay6. There are several reports of successfully EVAR performed in RT recipients7-9, but there are just two reported cases of EVAR followed by successful RT10,11. These were performed on aortic aneurysms. There are no reported cases of aorto-iliac aneurysm. This paper reported a case of aorto-iliac aneurysm in a patient with CRF under hemodialysis successfully corrected by EVAR succeeded by RT. Abstract


Case report
A 53-year-old man presenting with end-stage CRF secondary to hypertensive nephrosclerosis treated with hemodialysis.He did not present diabetes mellitus, but had a 40-year smoking history.His bilateral limb pulses were palpable and symmetric.He referred an asymptomatic abdominal mass, and an investigation with computed tomography (CT) scan revealed an infrarenal aortic aneurysm (5.0cm transverse diameter), extending to both common iliac arteries (3.0cm transverse diameter each) until its bifurcations (Figure1).He underwent EVAR through bilateral groin incisions, with placement of an Excluder ® endoprosthesis (W.L. Gore & Associates, Flagstaff, Arizona) with the following measures: • right main trunk 31mm/14mm/15cm; • left contralateral leg 16mm/14mm/14cm; • right extension 16mm/10mm/7cm; • left extension 16mm/14mm7cm.
In order to completely exclude the aneurysm, both hypogastric artery orifices were covered by the extensions.
No embolization coils were used.Completion angiogram showed adequate positioning of the endograft and no endoleak.He made a good recovery and, beside some transient thigh paresthesia, no complications were observed.Postoperative rectosigmoidoscopy showed no signs of bowel ischemia.The patient went on hemodialysis on the day after and was discharged three days after the procedure.One-month CT scan showed good graft positioning and no endoleak (Figure 2).
Four months after EVAR, he underwent RT.Through a right Gibson incision; he received a left cadaveric renal transplant with HLA matching A0B1DR2 and negative crossmatch.The gratf had two arteries on a Carrel patch, single vein and single ureter.At dissection, it was possible to palpate the endograft in the right external iliac artery, which had a normal aspect and pulse at its distal portion.No retroperitoneal fibrosis or inflammation was observed.The transplant arterial patch was sutured in the right external iliac artery 0,.5cm proximal to inguinal ligament by an end to side anastomosis using continuous polypropilene 6-0.The venous anastomosis was performed end-to-side in the external iliac vein using continuous polypropilene   5-0.The ureter was implanted using Lich-Gregoir technique.Just after the procedure, the kidney started to produce urine.There was no displacement of the endograft during surgery.No complications were observed and the patient was placed on an immunosuppression regimen of mycophenolate, tacrolimus and prednisone.Magnetic resonance imaging angiography (MRI-A) obtained five days after the surgery demonstrated good positioning of the aorto-iliac endograft and adequate perfusion of the renal graft (Figure 3).Creatinine levels dropped from a preoperative value of 6.2mg/dL to 1.6mg/dL at discharge eight days after transplantation.At office visits, creatinine levels were stable.The four-year follow-up with yearly MRI-A showed good positioning of the endograft without migration or endoleak.

Discussion
Aneurysmal disease involving aorta and both iliac arteries has not a simple treatment.Either open or endovascular approaches require advanced surgical skills.When associated renal disease is present, the future possibility of a RT must be considered and the ideal treatment must provide adequate conditions for it.Iliac vessels and pelvic space must be preserved.
Our patient was on hemodialysis and had a 5cm-aortoiliac aneurysm and was in the waiting line for RT.Although EVAR and RT simultaneous performance was described 12 , we decided to perform aneurysm repair first, according to published series [3][4][5] .The main advantage to treat the aneurysm before RT is to avoid ischemic and nephrotoxic complications in the renal graft, fact that would occur if RT were firstly performed.The choice of EVAR was based on reports of increased morbimortality in open surgery performed in patients like ours 1 .Another important reason is that EVAR does not require extensive dissection of the pelvic space, thus preserving it for a future RT.In fact, we also purposed open surgery, but the patient's choice was EVAR.
In order to completely exclude the aneurysm, covering of both hypogastric artery orifices were necessary.There are several description of ancillary procedures to provide flow to hypogastric arteries in EVAR such as surgical bypass 13 or endograft associated with crossover femorofemoral bypass 14 .However, these procedures involve respectively pelvic dissection and use of aorto-mono-iliac endograft, which would harm posterior RT.Thus, we chose covering hypogastric artery bilaterally.As in our case, Zander et al. 15 reported time-limited and insignificant complications with bilateral hypogastric artery occlusion in EVAR.Our patient had only transient thigh paresthesia and full recovery.No bowel ischemia and no buttock claudication were observed.Bilateral hypogastric artery occlusion, although risky, may be acceptable in cases with short therapeutic options, like ours.Recently available branched endograft for iliac arteries 16 would be suitable solution for preserve hypogastric flow in our case.
During RT after EVAR, possible complications are endograft dislodgment or migration, causing endoleak, and endograft limb thrombosis due to vascular clamping.These complications, which could lead to renal graft loss and EVAR failure, were not observed in our case.Care should be taken not to apply vascular clamps over the endograft.
After RT, MRI-A was used in the follow-up (six months after and then yearly) in order to avoid nephrotoxic effect of iodinated contrast.

Conclusion
Our experience with aorto-iliac aneurysm corrected by EVAR succeeded by RT concurs with previous reports of aortic aneurysm treated in the same way.In patients with CRF and aorto-iliac aneurysm, EVAR succeeded by RT is feasible and provides good results.

Figure 2 -
Figure 2 -Post-EVAR axial (A) and 3D reconstruction (B) CT scan, showing adequate positioning of the endograft and no endoleak.

Figure 3 -
Figure 3 -Post-RT MRI-A, showing good positioning of the aorto-iliac endograft and adequate perfusion of the renal graft.