Application of Protective Stents in Endovascular Repair of Acute Complicated Stanford Type B Aortic Dissections

Abstract

PURPOSE: To describe the use of protective stents in the endovascular repair of acute complicated Stanford type B aortic dissections. METHODS: From 2009 to 2011, 33 patients (27 men; mean age 47 years, range 31-73) with acute complicated Stanford type B aortic dissection underwent thoracic endovascular aortic repair (TEVAR) assisted by protective stents. In all cases, the proximal and distal landing zones differed in size by >5 mm, and the primary entry tear was in the proximal descending aorta. A bare self-expanding stent (protective stent) was deployed initially at the intended distal landing site of the primary stent-graft in the true lumen. The intention was that the bare stent would prevent excessive dilation of the distal end of the stent-graft in the vicinity of the entry tear, thus avoiding intimal rupture. RESULTS: Successful stent deployment and sealing of the entry tear was achieved in all patients. The median diameter and length of the protective bare stents was 20.3 mm (range 18-24) and 72.7 mm (range 60-80), respectively, while the corresponding dimensions of the covered stent-grafts were 32.8 mm (range 26-40) and 157.4 mm (range 120-200 mm), respectively. There was no stent twisting, migration, of rupture of the false or true lumen. Computed tomography 1 week postoperatively demonstrated closure of the primary entry tear with thrombosis of the false lumen in all cases. No patients were lost to follow-up, which has ranged from 3 months to 3 years. No late endoleaks or stent complications, such as angulation, dislodgment, persistent leaks, branch obstruction, or stent-graft migration, have been observed, and there has been no chronic progressive true or false lumen dilatation, recurrences, or deaths. CONCLUSION: Adjunctive use of a protective stent when treating acute Stanford type B aortic dissections in which the diameters of the proximal and distal landing zones differ by >5 mm is feasible and safe and provides good short-term outcomes.