Large endograft diameter is associated with poor outcomes following thoracic endovascular aortic aneurysm repair in Medicare beneficiaries.

OBJECTIVE

Multiple factors contribute to early and/or late failure after endovascular aortic repair. Notably, the impact of device-related parameters, specifically diameter, on postoperative outcomes following thoracic endovascular aortic aneurysm repair (TEVAR) has not been thoroughly explored. This study aimed to determine whether use of large diameter (≥40 mm) endografts increase the risk of adverse outcomes after TEVAR.

METHODS

All TEVAR procedures involving proximal Ishimaru zones 0 to 7 in the Society for Vascular Surgery-Vascular Quality Initiative (2016-2019) were identified. Patients were linked to Medicare claims data (VQI-VISION) to assess long-term outcomes. The cohort was stratified based on endograft diameter: ≥40 mm(vs <40 mm). Preoperative characteristics, operative variables, and postoperative outcomes were compared. The primary outcome was a composite of aortic-related reintervention, rupture, and all-cause mortality. Unadjusted and adjusted Cox regression analyses were performed across outcome measures.

RESULTS

A total of 2259 patients met inclusion criteria, with 681 (30%) receiving at least one ≥40 mm diameter endograft. Patients receiving large endografts (≥40 mm) were more likely to be men (n = 412; 61% vs n = 828; 53%; P = .0004), had larger preoperative aneurysm diameters (60 mm; interquartile range [IQR], 54-67 mm vs 54 mml IQR,40-61 mm; P < .0001), and had prior aortic surgery (n = 306; 45% vs n = 390; 25%; P < .0001). Patients with large endografts were more likely to have aneurysmal pathology (n = 528; 78% vs n = 935; 59%; P < .0001) as opposed to acute dissection/intramural hematoma/penetrating athersclerotic ulcer. Large endograft deployments were more likely to occur for disease extent involving the aortic arch and descending thoracic aorta (n = 463; 71% vs n = 873; 58%; P < .0001) rather than more distal thoracoabdominal disease. Procedures tended to be more complex for patients with large endografts, as evidenced by longer procedure times, increased fluoroscopy exposure, and higher contrast volume use. Patients with large endografts had significantly worse 30-day mortality (11% vs 8%; P = .02) and complication rates (32% vs 25%; P = .0006). The 1-year and 3-year composite rate of aortic-related reintervention, rupture, and all-cause mortality were significantly worse with large endografts (1-year: ≥40 mm, 37%; 95% confidence interval [CI], 33%-41% vs <40 mm, 30%; 95% CI, 28%-33%; log-rank P value = .002; 3-year: ≥40 mm, 60%; 95% CI, 55%-65% vs <40 mm, 48%; 95% CI, 44%-51%; P value < .0001). Independent predictors of the composite endpoint included endograft diameter ≥40 mm (hazard ratio [HR], 1.3; 95% CI, 1.1-1.5), aneurysm diameter (HR, 1.0; 95% CI, 1.0-1.02), and age (HR, 1.02; 95% CI, 1.01-1.03).

CONCLUSIONS

Large-diameter endografts (≥40 mm) are associated with worse outcomes following TEVAR. Although there was no significant difference in late rupture events, aortic-related reintervention and all-cause mortality were significantly worse at 3 years. Treatment success should be heavily scrutinized when using large diameter endografts, as these results identify a device-specific parameter that is strongly associated with longitudinal risks. Device regulators may need to reassess the efficacy of large diameter thoracic endografts.