Predictors of Blunt Thoracic Aortic Injury Requiring TEVAR in Patients with Left-Sided Hemothorax: Implications for Chest Drainage and Early CTA Assessment

Background: Blunt thoracic aortic injury (BTAI) is an uncommon but life-threatening consequence of blunt thoracic trauma. Left-sided hemothorax is frequently identified during initial evaluation and typically prompts early chest drainage. However, when an unrecognized BTAI is present, pleural decompression may precipitate hemodynamic instability. This study aimed to identify early predictors of BTAI requiring thoracic endovascular aortic repair (TEVAR) in patients presenting with left-sided hemothorax. Methods: We conducted a single-center retrospective cohort study including consecutive trauma patients aged ≥ 16 years with radiologically confirmed left-sided hemothorax between 2015 and 2025. Patients were stratified according to the need for TEVAR. Clinical, laboratory, and radiological variables available at emergency department admission were analyzed. Independent predictors of BTAI requiring TEVAR were identified using multivariable logistic regression. Results: Among 146 included patients, 27 (18%) underwent TEVAR for confirmed BTAI. Patients requiring TEVAR were generally younger and more frequently involved in high-energy trauma. Independent predictors of TEVAR included high-energy mechanism (p = 0.048), lower admission hemoglobin (p = 0.007), presence of extra-thoracic fractures (p < 0.001), and a higher number of right-sided rib fractures (p = 0.018). The volume of left-sided hemothorax was not independently associated with BTAI. The model demonstrated strong discriminative ability (AUC = 0.926). Conclusions: In trauma patients with left-sided hemothorax, BTAI requiring TEVAR may occur even in the presence of minimal pleural effusion. Readily available admission parameters may help identify patients who could benefit from a CT angiography-first approach rather than routine early chest drainage, except in cases of immediate life-threatening pleural compromise.