Early Experience with the Octopus Endovascular Strategy in the Management of Thoracoabdominal Aneurysms

Abstract

The Octopus endovascular strategy involves placement of multiple, stacked bifurcated grafts in the thoracic segment of a thoracoabdominal aneurysm (TAAA) to facilitate deployment of multiple parallel covered stents for visceral perfusion. This study aimed to review early outcomes of the Octopus TAAA repair strategy at a tertiary, high-volume referral center. All patients who underwent this Octopus procedure from 2015 to 2018 were reviewed from a prospectively collected single-institution registry. Demographics, comorbidities, and aneurysm anatomy including side and extent, perioperative data including blood loss, length of procedure length of stay, morbidity, and mortality up to 3years after the procedure were elevated. A total of 21 patients (48% female, age 72.9years) underwent the Octopus procedure over the study period. Mean TAAA diameter was 6.7cm, with 14% dissection related and 86% degenerative TAAA. All patients had been turned down for open repair and 3 (14%) were performed urgently of which 2 were ruptures. TAAA extent was 9% type 2, 62% type 3, and 29% type 4. A mean of 3.04 branches were revascularized per patient, with the superior mesenteric artery (SMA) (90%) perfused through its own limb, and both renals usually reconstructed in parallel graft fashion (left 90%, right 85.7%) with the distal abdominal extension through one of the limbs. Mean operative time was 8hr, fluoroscopy time 164min, contrast 182mL, and blood loss 807mL. We staged the thoracic and juxtavisceral portions of the cases in 24% of patients. 90% of cases were able to be completed with exclusion of the TAAA and all planned visceral branches cannulated. Perioperative complications included paraplegia (19%) (13.3% permanent, 26.6% temporary), acute kidney injury (24%), prolonged ventilation (19%), myocardial infarction (4.9%), and ischemic bowel (4.8%). Median follow-up was 13.5months (range 1-26months). At latest follow-up, type I endoleak rate was 9.5%, with all being treated with proximal cuffs. Other second interventions included restenting of a right renal, angioplasty of an iliac limb kink, and type 2 endoleak coiling. Primary patency of visceral branches was 93.8% at latest follow-up (celiac 100%, SMA 94.7%, right renal 88.9%, left renal 94.8%). In-hospital all-cause mortality rate was 14.2%, with 30-day survival being 90.5%, 6-month survivalwas 88.3%, one-year survival 71.4%, and 3-year survival was 52.1%. The Octopus procedure is a high-risk option for urgent or emergent endovascular TAAA repair with off-the-shelf devices in patients who are not candidates for open repair.