VESS07 - Real-World TAMBE Outcomes Among Medicare Beneficiaries

Objectives: The Thoracoabdominal Branch Endoprosthesis (TAMBE) recently received FDA approval as the first off-the-shelf endovascular device for complex aneurysmal disease involving the visceral aorta. Prior to formal FDA approval, a pivotal pre-approval analysis demonstrated high procedural success, low perioperative morbidity, and no perioperative mortality. As such, we sought to evaluate real-world adoption patterns and perioperative outcomes following TAMBE implementation nationwide.

Methods: We identified all Medicare Fee-for-Service beneficiaries undergoing TAMBE repair between 10/1/2024 and 12/31/2024. TAMBE cases were identified using CPT X2VE3SA. Thirty-day outcomes included all-cause mortality, stroke, MI, reintervention, acute kidney injury (AKI), spinal cord ischemia, and bowel ischemia. To provide a historical benchmark, we compared outcomes following TAMBE approval in 2024 with all Medicare beneficiaries undergoing ≥4-vessel fenestrated or branched EVAR (F/BEVAR) in 2023. Consistent with CMS small-cell suppression policy, outcome frequencies of < 11 events ( < 4.2% for TAMBE; < 1.6% for F/BEVAR) were masked and not reported. Logistic regression models adjusted for available and relevant demographic, anatomic, and comorbidity characteristics.

Results: Overall, 262 TAMBE procedures were identified among Medicare beneficiaries in 2024. Mean age was 75.6 years; 72% were male and 88% white. The majority of TAMBE procedures were elective (89%) and were coded as being primarily performed for abdominal aortic aneurysms (66%), followed by thoracoabdominal aneurysms (30%). At 30 days, mortality was 7.9% and acute kidney injury was 7.3% (Table I). All other adverse outcomes – including stroke, MI, reintervention, spinal cord ischemia, and bowel ischemia – occurred in < 4.2% of patients and were suppressed per CMS policy. When compared with patients undergoing ≥4-vessel F/BEVAR in 2023, TAMBE was associated with significantly higher 30-day stroke ( < 4.2% vs. < 1.6%, unadjusted Odds Ratio [uOR] 11.4, 95% confidence interval [1.26-103.88]) and mortality (7.9% vs 4.1%; uOR 1.96[1.11-3.48]). After adjustment, the significance persisted, with TAMBE demonstrating nearly nine-times higher risk of stroke (Adjusted OR, 8.96[1.42-56.73]) and more than two-times higher risk of death (aOR 2.09[1.15-3.79]).

Conclusions: Despite encouraging pre-market reports, real-world Medicare data demonstrate higher 30-day stroke and mortality following TAMBE compared to contemporary complex endovascular repair strategies. Although the etiology of these differences is unclear, the elevated stroke signal – potentially influenced by upper extremity access required within the TAMBE instructions for use – and higher mortality may reflect challenges associated with early post-approval dissemination beyond centers associated with the initial trials. Ongoing post-market surveillance and careful patient selection remain vital as TAMBE adoption continues to expand.