Outcomes following thoracic endovascular aortic repair for blunt thoracic aortic injury stratified by Society for Vascular Surgery grade

Abstract

Objectives: Although the Society for Vascular Surgery (SVS) aortic injury grading system is used to depict the severity of injury in patients with blunt thoracic aortic injury, prior literature on its association with outcomes after thoracic endovascular aortic repair (TEVAR) is limited.

Methods: We identified patients undergoing TEVAR for BTAI within the VQI between 2013 and 2022. We stratified patients based on their SVS aortic injury grade (grade 1, intimal tear; grade 2, intramural hematoma; grade 3, pseudoaneurysm; and grade 4, transection or extravasation). We assessed perioperative outcomes and 5-year mortality using multivariable logistic and Cox regression analyses. Secondarily, we assessed the proportional trends in patients undergoing TEVAR based on SVS aortic injury grade over time.

Results: Overall, 1311 patients were included (grade1, 8%; grade 2, 19%; grade 3, 57%; grade 4, 17%). Baseline characteristics were similar, except for a higher prevalence of renal dysfunction, severe chest injury (Abbreviated Injury Score >3), and lower Glasgow Coma Scale with increasing aortic injury grade (P_trend < .05). Rates of perioperative mortality by aortic injury grade were as follows: grade 1, 6.6%; grade 2, 4.9%; grade 3, 7.2%; and grade 4, 14% (P_trend = .003) and 5-year mortality rates were 11% for grade 1, 10% for grade 2, 11% for grade 3, and 19% for grade 4 (P = .004). Patients with grade 1 injury had a high rate of spinal cord ischemia (2.8% vs grade 2, 0.40% vs grade 3, 0.40% vs grade 4, 2.7%; P = .008). After risk adjustment, there was no association between aortic injury grade and perioperative mortality (grade 4 vs grade 1, odds ratio, 1.3; 95% confidence interval, 0.50-3.5; P = .65), or 5-year mortality (grade 4 vs grade 1, hazard ratio, 1.1; 95% confidence interval, 0.52-2.30; P = .82). Although there was a trend for decrease in the proportion of patients undergoing TEVAR with a grade 2 BTAI (22% to 14%; P_trend = .084), the proportion for grade 1 injury remained unchanged over time (6.0% to 5.1%; P_trend = .69).

Conclusions: After TEVAR for BTAI, there was higher perioperative and 5-year mortality in patients with grade 4 BTAI. However, after risk adjustment, there was no association between SVS aortic injury grade and perioperative and 5-year mortality in patients undergoing TEVAR for BTAI. More than 5% of patients with BTAI who underwent TEVAR had a grade 1 injury, with a concerning rate of spinal cord ischemia potentially attributable to TEVAR, and this proportion did not decrease over time. Further efforts should focus on enabling careful selection of patients with BTAI who will experience more benefit than harm from operative repair and preventing the inadvertent use of TEVAR in low-grade injuries.

Keywords: Blunt thoracic aortic injury; SVS Aortic Injury Grading; TEVAR; Thoracic injury.