Satisfactory Long-term Outcomes of Thoracic Endovascular Aortic Repair With a Bare Stent for Acute Complicated Type B Aortic Dissections

PURPOSE: To compare the clinical outcomes after thoracic endovascular aortic repair (TEVAR) with a bare stent to those after TEVAR alone in patients with complicated acute type B aortic dissection (cATBAD). MATERIALS AND METHODS: A prospective, randomized trial was conducted at 2 medical centers in China between 2010 and 2013. Patients with cATBAD were randomly assigned to receive TEVAR with a bare stent (n=42) or TEVAR only (n=42). Patients were scheduled to undergo computed tomography angiography at 3, 6, and 12 months and then annually to 5 years. The primary endpoint was all-cause mortality at 5 years; secondary outcomes were a composite of complications (endoleak, stent-graft-induced new entry, aortic rupture, and secondary intervention) and aortic remodeling at 1 and 5 years. RESULTS: All-cause death occurred in 1 (2.4%) patient in the TEVAR with bare stent group (lung cancer) and 5 patients (11.9%) in the TEVAR group (4 aorta-related) during the 5-year follow-up (log-rank p=0.025). The 1- and 5-year rates of complications and secondary interventions did not differ between the groups. Patients in the TEVAR with bare stent group had higher increases in the thoracic true lumen diameter (19.7±3.6 vs 17.0±6.2 mm, p=0.018) and abdominal true lumen diameter (13.7±4.8 vs 7.2±6.1 mm, p<0.001) and a higher incidence of complete false lumen thrombosis (80.9% vs 47.6%, p=0.005) at the 1-year follow-up. However, no between-group differences in the changes of aortic remodeling parameters were observed between the 1- and 5-year follow-up periods. CONCLUSION: The addition of a distal bare stent to a thoracic stent-graft during TEVAR was associated with significantly improved long-term survival in cATBAD patients vs TEVAR only, likely due to the prevention of true lumen collapse and improvement of complete false lumen thrombosis of the dissected aorta.