Outcomes Following Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury Stratified by Society for Vascular Surgery Grade.

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

METHODS: We identified patients undergoing TEVAR for BTAI within the VQI between 2013-2022. 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/extravasation). We assessed perioperative outcomes and 5-year mortality utilizing multivariable logistic and Cox regression analyses. Secondarily, we assessed proportional trends in patients undergoing TEVAR based on SVS aortic injury grade over time.

RESULTS: Overall, 1,311 patients were included (grade1: 8%; grade 2: 19%; grade 3: 57%; grade 4: 17%). Baseline characteristics were similar except for higher prevalence of renal dysfunction, severe chest injury (abbreviated injury score >3), and lower GCS 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: grade 1: 11%; grade 2: 10%; grade 3: 11%; and grade 4: 19%; (p=.004). Grade 1 patients 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). Following risk-adjustment, there was no association between aortic injury grade and perioperative mortality (grade 4 vs. grade 1: odds ratio (OR): 1.3 [95%CI: 0.50-3.5]; p=.65), or 5-year mortality (grade 4 vs grade 1, HR:1.1 [95%CI: 0.52-2.3]; p=.82). While there was a trend for decrease in the proportion of TEVAR patients 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: Following TEVAR for BTAI, there was higher perioperative and 5-year mortality in grade 4 patients. 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. Over 5% of BTAI patients 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 BTAI patients who will experience more benefit than harm from operative repair and preventing the inadvertent use of TEVAR in low grade injuries.