Presentations

Abstract

Introduction: Treatment of abdominal aortic aneurysms (AAAs) is generally pursued via open, endovascular, or hybrid approaches depending on patient anatomy and comorbidities. Physician-modified endografts (PMEGs) are back table modified prior to deployment to exclude the aneurysm, maintaining flow to mesenteric and renal arteries in patients with inadequate seal zones. Displacement of the graft during deployment can lead to acute mesenteric or renal ischemia. Here, we present a case where a displaced and kinked PMEG was rescued using a novel pullback technique with endoscopic biopsy forceps.

Case Information: An 81-year-old male with prior endovascular aortic repair (EVAR) for AAA, thoracic endovascular aortic repair (TEVAR) for a penetrating atherosclerotic ulcer, and extensive cardiopulmonary and renal comorbidities presented with back pain, aneurysmal sac enlargement from 3 to 6.2 cm over three years, and periaortic stranding concerning for impending rupture. Computed tomography angiography (CTA) demonstrated a type Ia endoleak and occlusion of the right renal artery leading to kidney atrophy. He was a poor candidate for open repair. His solitary left kidney precluded off-the-shelf devices. Urgent endovascular repair was planned using a PMEG. Given the patient's urgent presentation, a PMEG solution was entertained and physician modification of the Zenith Alpha Thoracic Endovascular Graft (Cook Medical, Bloomington, IN) was performed adding fenestrations for the celiac, superior mesenteric, and left renal arteries. Bilateral common femoral arteries were accessed, and the PMEG was introduced and partially deployed at the infrarenal aorta. The pre-marked fenestrations were aligned anatomically with computed tomography (CT) fusion assistance. All fenestrations were cannulated. The PMEG was fully deployed prior to fenestration stenting. A partial kink in the distal landing zone within the old EVAR was noted with incomplete apposition of the PMEG and existing abdominal endograft. Balloon angioplasty was attempted without success. Endoscopic forceps were advanced using a 7 French (Fr) sheath from the right common femoral artery, and downward traction was applied to the left lateral aspect of the PMEG. The kink resolved after the graft was carefully pulled down and all fenestrations were noted to be in proper alignment. Target vessel stents were deployed and angiography confirmed patency of all stents with successful aneurysm exclusion. The patient tolerated the procedure well. During recovery he developed pneumonia before being discharged on postoperative day (POD) 16 to a skilled nursing facility. He had multiple admissions in the following months with cardiopulmonary issues unrelated to aneurysmal complications. Ultimately he transitioned to comfort measures, expiring on POD 65.

Discussion/Clinical Findings: Multiple techniques have been described for the repair of type Ia endoleaks after EVAR including open surgical repair, endoanchors, extension of the initial repair with additional stents and or grafts, and fenestrated endograft implantation. A 2021 study by Doumenc et al suggested that fenestrated EVAR (FEVAR) had decreased early morbidity compared to open surgical repair. O'Donnell et al found that open repair is associated with better long term survival, while endovascular repair displayed better results in patients with advanced age or comorbidities. Given this patient's extensive comorbidities, his operative risks were prohibitive for open repair, prompting endovascular repair with a fenestrated PMEG. PMEG use is not currently FDA-approved, but given this patient's complicated anatomy, it was deemed the best option available. The instructions for use of the Zenith Alpha Thoracic Endovascular Graft (Cook Medical) chosen for the procedure state that the diameter of the distal and proximal aneurysmal neck must be between 20-42 mm. The choice of the 32 mm graft allowed for adequate seal in the previous endograft which was measured to be 23 mm. An alternative option would be coverage of the left renal artery rather than fenestration, but this would have mandated permanent dialysis as the patient only had one functioning kidney due to an occluded right renal artery. During PMEG deployment, the resulting kink was possibly due to the re-sheathing process, however an endograft kink can occur for a variety of reasons when overlapping two endografts, with sizing, deployment, and placement issues being common causes (e.g. tilt and angulation). After an unsuccessful attempt at balloon angioplasty to resolve the kink, there were no well-established techniques available to address the issue endoscopically, usually necessitating a transition to open repair. The patient's comorbidities offered a grim prognosis for open repair, so an alternative approach was taken using endoscopic forceps as described above.

Conclusion: We detail the use of a PMEG to manage a patient with juxtarenal graft endoleak from previous EVAR. During PMEG deployment, a kink in the distal landing zone prevented an adequate seal and did not resolve with balloon angioplasty. PMEG pullback with endoscopic biopsy forceps resolved this kink and ensured proper graft alignment. This technique successfully created optimal overlap between the two endografts and prevented open conversion.