Durability of a low-profile stent graft for thoracic endovascular aneurysm repair

The introduction of lower profile endografts expanded the application of aortic endovascular repair. However, evidence about their durability is still scarce. The objective of this study was to assess longer term durability of the Zenith Alpha Thoracic Stent Graft (Cook Inc, Bloomington, Ind) after thoracic endovascular aortic repair.

Prospectively collected data of all patients treated for thoracic aortic aneurysms or penetrating aortic ulcers and having computed tomography angiography-based follow-up of ≥12 months were retrospectively analyzed. The primary end point was ongoing clinical success. Among the secondary end points, stent graft migration and fracture were analyzed.

Between August 2010 and October 2015, 70 consecutive patients were treated in a single center with the Zenith Alpha stent graft. With computed tomography angiography-based follow-up of 22.3 ± 15.9 months, ongoing clinical success was 87.1%. There were three cases of type IA endoleak (4.3%), two cases of type IB endoleak (2.9%), and one case of aneurysm sac enlargement (1.4%). Five patients died postoperatively (7.1%). No type III or type IV endoleak was detected; there was one case of distal stent graft migration and no stent fracture. Reintervention was necessary in one case (1.4%) of a combined type IA and type II endoleak. There were no conversions to open repair and no ruptures or intraoperative deaths. All-cause mortality was 17.1% at 76 months.

The Zenith Alpha Thoracic Stent Graft appears to maintain favorable results in a longer time frame with a low incidence of aneurysm sac growth and migration. Results from multicenter prospective trials are needed to validate these data.