A Novel Technique and Outcomes for Transcaval Endoleak Embolization

Abstract

Strategies for embolization of type 2 endoleaks include translumbar, transgraft, transarterial, and transcaval approaches. The transcaval approach is limited by an inconsistent ability to access the aortic sac and the risk of puncturing and damaging the endograft or adjacent structures. We describe a novel technique for caval to aortic aneurysm sac access and report early outcomes. A retrospective review of all patients who underwent transcaval embolization (TCE) at a tertiary referral center. From March 2019 to June 2021, 12 patients were identified to have undergone a novel approach to transcaval aortic sac access using a 0.014″ heavy weight tip wire guide and continuous current electrocautery to create the connection between the inferior vena cava and aortic aneurysm sac. The endoleak outflow vessel is then selectively embolized with coils or liquid embolic agents. When selective embolization was not possible, the aneurysm sac was instilled with liquid embolic agents to induce thrombosis. Twelve patients underwent transcaval embolization using this method over the 3-year period. The average patient age was 79.2±6.2years and 10/12 (83.3%) were male. A high rate of comorbidities was noted in the cohort. Transcaval access into the aortic sac was achieved in all patients, while selective cannulation of outflow vessels was accomplished in 2/12 (16%) target vessels. Of these, both cases had vessels embolized using detachable coils and liquid embolic agents. Nonselective embolization was performed using liquid embolic and thrombotic agents in the other 10/12 cases. There was one perioperative complication of minor bleeding (1/12, 8.3%). Two patients were observed in intensive care unit for back pain. A persistent endoleak was identified on postoperative imaging performed at 30days in 4/12 (33.3%) patients. Sac enlargement > 5mm following TCE was observed in 3/12 (25%) patients. Three patients underwent open conversion with endovascular aneurysm repair explant. One patient was explanted at 1month after failure to embolize the endoleak flow channel using TCE. A second was explanted for persistent endoleak found to be a Type IIIb with aortic diameter growth > 5mm at 15-month follow-up. The third explant was performed for aortic sac infection at 4months postprocedure without endoleak. TCE is an adjunctive technique to treat endoleaks in patients who have either failed transarterial or translumbar access. An electrified 0.014″ chronic total occlusion wire technique for transcaval access to the aortic sac for endoleak embolization can be successful in all cases without significant acute morbidity or mortality. The transcaval approach is still limited by ability to steer catheters and microcatheters into the outflow vessels with a resultant persistent endoleak and eventual need for explant.