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W. Michael Park, MD
The patient is a 79 year old woman with an 8.7cm infrarenal abdominal aortic aneurysm (figure 1) with bilateral iliac arterial occlusion.
She was turned down for repair due to her medical comorbidities and inability to access her aorta for endovascular aneurysm repair (EVAR) due to her iliac arterial occlusions (figure 2). She was asymptomatic from her aneurysm but did complain of calf claudication with walking short distances.
The CT scan, which was an outside study, showed the aneurysm to be saccular (figure 3) compounding the high risk of rupture already conferred by its large size. After reviewing the images, we decided that even with her medical comorbidities, the immediate and high risk of rupture and the feasibility of repair compelled us to recommend repair.
The Surgery - A Five Part Process
In planning this operation, I broke it down into five parts.
The first was access to the aortic bifurcation via the right common iliac artery and to both common femoral arteries. This was done via a right retroperitoneal exposure and bilateral groin exposures.
The second step was anastomosis of a 10mm graft end to end to the endarterectomized, reopened proximal common iliac artery. This would allow for access to the aorta and to the left iliac system in an antegrade direction.
This along with left groin exposure for retrograde access allowed for the third step which was left external iliac artery recanalization.
The fourth step was EVAR, in this case with a AFX graft (Endologix). And the final step was revascularizing the right leg by anastomosing the conduit to the right common femoral artery.
Retroperitoneal access of the right common iliac artery is facilitated by use of a fixed retractor system. Figure 4 shows the three initial steps.
The conduit used was a PTFE graft (Propaten) which I anastomosed end to end to the common iliac artery which I endarterectomized to re-establish patency. Through the conduit, a sheath was placed and up and over access of the bifurcation was achieved.
Retrograde wire access allowed me to localized the external iliac artery origin, allowing for antegrade wire access (Figure 5).
This was then used to balloon the external iliac artery then deliver a large nitinol stent (Zilver 12x80) across the occlusion and post-dilate this to 8mm. This established access from the left groin (Figure 6).
Once this was done, EVAR with the AFX device was performed via the conduit and the recanalized left iliac system (Figure 7). The conduit was then used as a graft to deliver blood to the right leg by anastomosing it to the right common femoral artery. The final arteriogram showed successful exclusion of the aortic aneurysm with re-established flows to both legs (Figure 8). She recovered well and was discharged several days after her procedure.
This was a challenging case that was made feasible by organizing the repair in to achievable parts. This division of the operation into "way points," is similar to the way a golfer would tackle a difficult par 5 by creating a game plan for avoiding the pitfalls of the course while playing to the player's strengths.
Each steps also had a bailout option, a plan B, which in this patient's case was creation of an aorto-uni-iliac stent graft and femorofemoral bypass. This particular stent graft was chosen because it allowed preservation of the aortic bifurcation for future interventions on the legs and because the particular design of the aortic cuff would sealed what was a very challenging aortic neck.