Adherence to Instructions for Use and Mid-Term Outcomes of Endovascular Repair in Thoracic Aortic Disease from the Gore Global Registry for Endovascular Aortic Treatment (GREAT).

BACKGROUND

To examine whether adherence to device instructions for use (IFU) impacts outcomes after thoracic endovascular aortic repair (TEVAR) for descending thoracic aortic aneurysm (DTAA) and penetrating aortic ulcer (PAU).

METHODS

This retrospective analysis of the prospective, multicenter Gore Global Registry for Endovascular Aortic Treatment (GREAT) (NCT01658787) included 939 patients treated with GORE® TAG® or Conformable TAG® devices between 2010 and 2016. For the present study, we evaluated 334 elective patients with DTAA or PAU who underwent TEVAR in proximal landing zones 2-4, with 5 years of follow-up (FU). Patients were categorized as treated inside IFU (iIFU) or outside IFU (oIFU). Primary outcomes included survival, aortic-related mortality, serious adverse events (SAEs), and device-/procedure-related complications. Secondary outcomes included endoleak, reintervention (RI), and device integrity. Cox proportional hazards models assessed associations between IFU status and outcomes.

RESULTS

Among 334 patients (median age, 71 years; 41% female), 208 (62%) were treated iIFU and 128 (38%) oIFU. The most common deviations were inadequate proximal landing zone (56%) and distal diameter mismatch (47%). Baseline demographics and comorbidities were similar, although coronary heart disease was more prevalent in iIFU patients. Over 5 years, survival (56.1% vs. 62.8%, P = 0.50), aortic-related mortality (4.3% vs. 4.7%, P = 0.90), SAEs (64.3% vs. 61.4%, P = 0.60), and device-/procedure-related SAEs (24.0% vs. 26.7%, P = 0.60) did not differ significantly between iIFU and oIFU groups. Endoleaks were infrequent, with no significant differences by IFU status, though type III endoleaks occurred only in oIFU patients (1.6%). Device migration, fracture, or compression was rare. RIs occurred in 15% of iIFU and 20% of oIFU patients (P = 0.30). Cox analysis demonstrated a significantly increased hazard for "other" RIs in oIFU patients (hazard ratio, 2.38; 95% confidence interval, 1.13-5.02; P = 0.022), whereas risks for device-/procedure-related RIs, endoleaks, or mortality were not significantly different.

CONCLUSION

Elective TEVAR is frequently performed oIFU, largely due to proximal landing zone and distal diameter constraints. In this multicenter registry, oIFU treatment was not associated with significantly worse survival, aortic-related mortality, or major device-related complications over 5 years. However, the increased risk of secondary RIs highlights the need for careful patient selection, structured FU, and further prospective research to define which anatomic deviations can be safely tolerated in clinical practice.