Purpose: This study was performed to investigate the long-term effect of chimney technique using balloon-expandable bare-metal stents (BMSs) to preserve the supra-arch branches in type B aortic dissection (TBAD).
Methods: Fifty patients with TBAD treated by thoracic endovascular aortic repair with the chimney technique (chTEVAR) using balloon-expandable BMSs from July 2009 to December 2013 were retrospectively assessed. Follow-up computed tomography angiography was performed to assess the postoperative outcomes. The primary end point was a persistent type Ia endoleak (ELIa). The secondary endpoints were chimney stent (CS)-based complications (stenosis, occlusion, fracture, or transposition), all-cause mortality, reintervention, and stroke.
Results: Fifty supra-arch branches (left common carotid artery, n = 11; left subclavian artery, n = 39) were preserved via the chimney technique with 50 balloon-expandable BMSs. The technical success rate was 100%. An immediate ELIa was discovered in 9 (18%) patients. The median survival duration during follow-up was 77.3 months. Five (10%) patients had a persistent ELIa; 3 of these patients had an immediate ELIa. Asymptomatic CS-based complications were found in 3 (6%) patients. The all-cause mortality rate was 8% (4/50); 2 deaths were aortic-related deaths. Five (10%) patients underwent a reintervention. During the estimated 36-month survival period, the survival rate, the rate of freedom from persistent ELIa, and the rate of freedom from reintervention were 93.87%, 89.48%, and 95.56%, respectively.
Conclusions: The long-term outcomes showed that chTEVAR using balloon-expandable BMSs was safe and feasible for preservation of the supra-arch branches. Evaluation of more patients with a longer follow-up period is needed.
Keywords: bare stent; chimney technique; endoleak; thoracic endovascular aortic repair; type B aortic dissection.