Feasibility of Direct Intercostal and Lumbar Artery Revascularization to Prevent Spinal Cord Ischemia Associated with Endovascular Thoracoabdominal Aortic Repair

Abstract

Despite advances in complex endovascular aortic repair techniques, spinal cord ischemia (SCI) is still a devastating complication following endovascular thoracoabdominal aortic repairs. Current preventive strategies such as staged repair, temporary sac perfusion, hemodynamic management, and spinal drainage, focus on augmentation of spinal perfusion through collateral networks. Novel strategies to preserve key intercostal/lumbar arteries have been described including endovascular incorporation of fenestrations/branches and extra-anatomic bypass. We report our early results of patients who underwent direct intercostal/lumbar artery revascularization using endovascular or extra-anatomic approaches for fenestrated-branched endovascular aortic repairs (FBEVAR). A retrospective review of consecutive patients who underwent FBEVAR with intercostal/lumbar artery revascularization from 2018 to 2022 was performed. Patient characteristics, intraoperative details, and outcomes including SCI and branch occlusions were evaluated. Among 318 patients who underwent FBEVAR during the study period, 12 patients were included in the study. Aortic pathologies consisted of degenerative aneurysms (33%), postdissection aneurysms (33%), extensive penetrating aortic ulcers with intramural hematoma (25%), and visceral patch pseudoaneurysm (8%). Full thoracoabdominal coverage was required in eight patients and supraceliac coverage >10 cm was required in four. Nine patients received endovascular incorporation (Fig 1), including directional branches (5/9), unstented fenestrations (2/9), and stented fenestration (1/9). Three patients received extra-anatomic subcutaneous femoral-to-radicular artery bypass using a composite graft of polytetrafluoroethylene and saphenous vein (Fig 2). Our institutional SCI prevention protocol, consisting of prophylactic cerebral spinal fluid drain for high-risk patients, hemodynamic augmentation, and oxygen supplementation, was followed. Prophylactic cerebral spinal fluid drain was placed in nine patients. One patient had unsuccessful drain placement attempts. Two patients who had selective angiography identifying the great anterior radiculomedullary artery, did not undergo drain placement. Total number of target vessels for FBEVAR was 4.2 with a fluoroscopy time 66 ± 31 minutes, and contrast usage of 109 ± 51 mL. There were no in-hospital mortalities. One patient died of intracranial hemorrhage after sustaining a fall from a ladder 32 days after discharge. Tarlov grade II SCI were seen in two patients (one endovascular, one extra-anatomic bypass), which resolved before discharge. At median follow-up of 13 months (range, 13 days to 37 months), three patients had thrombosed intercostal/lumbar branches (one extra-anatomic bypass, two endovascular branches) with no new SCI symptoms. In patients at high risk for SCI undergoing FBEVAR, direct revascularization of an intercostal or lumbar artery is feasible using endovascular or extra-anatomic bypass approach. Further studies are planned to identify key contributing intercostal and lumbar arteries and optimization of revascularization strategies.Fig 2Extra-anatomic, profunda femoris to L1 radicular artery bypass using a composite polytetrafluoroethylene-saphenous vein conduit.View Large Image Figure ViewerDownload Hi-res image Download (PPT)