The role of heparin in endovascular repair of blunt thoracic aortic injury

Objective: Early diagnosis and treatment are essential to improve survival of patients with blunt thoracic aortic injury (BTAI). Often, aortic surgical intervention may be delayed because of increased risk of bleeding with heparin, particularly in polytrauma victims. We believe that surgical delay may be remedied by proceeding without heparinization. This study reviewed the outcome of patients subjected to thoracic endovascular aortic repair (TEVAR) under full, low-dose, and no intraoperative systemic heparinization. Methods: There were 77 cases of confirmed BTAI identified and retrospectively analyzed at a high-volume urban trauma center during a period of 15 years (March 2003-September 2017). Patients were stratified into three groups on the basis of the intraoperative use of heparin during TEVAR, as follows: full heparin (FH), low-dose heparin (LH), and no heparin (NH). Baseline characteristics including the patients' demographics, diagnostic laboratory data and imaging studies, operative reports, postoperative complications, embolic and bleeding outcomes, and mortality data were reviewed. Results: Of the 77 total patients who underwent TEVAR for BTAI, 42 patients received full-dose heparinization, 18 received low-dose heparin, and 17 had no use of systemic heparin. There was no significant difference in age, sex, body mass index, or smoking history. The most common mechanism of injury was motor vehicle collision. Grade 3 (pseudoaneurysm) was the predominant type of BTAI (FH, 69.0%; LH, 61.1%; NH, 76.5%; P = .23). The mean interval between admission and repair was three times longer in the FH group than in the NH group (FH, 2.33 days; NH, 0.76 day; P = .091). The mean time in the intensive care unit was shorter in the NH group vs the FH group (15 days vs 26.21 days; P = .025). Thromboembolic and bleeding outcomes and mortality rates were comparable in all three groups; 57 patients continued follow-up for a mean time of 30.99 months. Conclusions: Our study shows no statistically significant difference in outcomes between the heparinized and nonheparinized groups. The primary benefit of the NH group is seen in time to repair. Although not statistically significant, the mean time to repair was three times longer in the FH group. Patients in the NH group also benefited from prompt intervention and treatment. Therefore, intraoperative heparinization in critically ill patients with BTAI undergoing TEVAR remains at the surgeon's discretion, although the lack of heparinization appears to be a safe and potentially faster alternative, particularly in the polytrauma patient.