Early outcomes of off-the-shelf Thoracoabdominal Multibranch Endoprosthesis during premaket vs postmarket approval periods.

BACKGROUND

The Thoracoabdominal Multibranch Endoprosthesis (TAMBE, W. L. Gore & Associates) is the first off-the-shelf four-vessel inner-branched endograft to obtain commercial approval for complex abdominal and thoracoabdominal aortic aneurysms. Although trial results are excellent, there is a paucity of data on the outcomes and usage pattern of TAMBE, after commercial approval. These data represent our early outcomes of patients who received TAMBE during premarket and postmarket approval periods, including off-label applications.

METHODS

Consecutive patients who received TAMBE at one institution from April 2020 to January 2025 were reviewed. Baseline characteristics including underlying aortic pathology, extent, urgency of repair, and off-label use were compared between those during premarket and postmarket periods. Intraoperative metrics and 30-day outcomes were compared.

RESULTS

We included 59 patients, with 13 in the premarket and 46 in the postmarket groups. Extent I, II, and III thoracoabdominal aortic aneurysms were more commonly treated during the postmarket period (1/13 vs 17/46). Compassionate, off-label TAMBE was performed in 2 patients during the premarket period (for a previously failed endograft and a chronic aortic dissection), and 35 patients were repaired using TAMBE in off-label fashion during the postmarket period. Off-label uses during the postmarket period include chronic dissection (n = 7), previous failed endograft (n = 13), combined with thoracic branch endoprosthesis or iliac branch endoprosthesis (n = 6), total transfemoral implantation (n = 13), contained rupture (n = 3), and occluded target vessels requiring intentional occlusion (n = 4). There were no significant differences in operative time (273 minutes vs 258 minutes; P = .576), fluoroscopy time (49 minutes vs 57 minutes; P = .180), and contrast (113 mL vs 119 mL; P = .269) during the premarket period vs the postmarket period. Technical success was 100% for the premarket and 98% for the postmarket groups (P = 1). The 30-day mortality rates was 0% for both groups. Major adverse events at 30 days were seen in 8% and 20% of the premarket and postmarket patients, respectively (P = .432). No premarket patients and 4% of postmarket patients required dialysis. The 30-day reintervention rate was 15% for both the premarket and postmarket groups (P = 1). The 30-day target vessel instability rate was 8% and 7% for the premarket and postmarket groups, respectively (P = .533). The 30-day spinal cord ischemia rate was 8% and 20%, respectively (P = .432). The target vessel patency rate was 93% and 91% for premarket and postmarket groups, respectively (P = 1).

CONCLUSIONS

Commercial approval of TAMBE was followed by increased application of the device beyond its instructions for use, without increased 30-day MAE. Although this finding indicates that TAMBE is a promising technology with wider potential applicability, robust follow-up data through a postmarket multicenter registry is critical for defining its future role.