Endovascular Treatment of Complex Aneurysms with the Use of Covera Stent Grafts

Endovascular Treatment of Complex Aneurysms with the Use of Covera Stent Grafts 

Clinical Question
To characterize the short-term results of the Covera stent for the reconstruction of target vessels in complex aneurysms and assess the safety and efficacy of this stent.

Take-away Point
The Covera self-expanding stent offers good short term patency in chimney, branched, and fenestrated EVAR procedures.

Reference
Caradu C, Dubourg A, Colacchip E, Midy D, Bérard X, Ducasse E. (2019). Endovascular Treatment of Complex Aneurysms with the Use of Covera Stent Grafts. J Vasc Interv Rad, 30:1942-1948. doi:10.1016/j.jvir.2019.05.004

Click here for abstract

Study Design
Nonrandomized, monocentric single-arm evaluation study

Funding Source
None

Setting

Dept of Vascular Surgery, Université de Bordeaux, France; Dept of Vascular Surgery, University Hospital of Poitiers, France; University Hospital of Padova, Italy




Figure 3. (a) Preoperative CT angiogram of an 84-year-old male patient showing a 60-mm type 3 thoracoabdominal aneurysm treated by using (b) a sandwich technique, with covered chimneys constructed using a self-expanding covered stent for the celiac trunk, the superior mesenteric artery, and both renal arteries. (c) The contrast-enhanced CT scan shows the positioning of the 4 self-expanding covered stents positioned between the 2 thoracic devices. (d) 3D reconstruction confirms the positioning of the devices and the preserved patency of the target arteries.

Summary

This single-center study assesses the safety and efficacy of the new Covera self-expanding stent for the use of chimey EVAR, branched EVAR (B-EVAR) and fenestrated EVAR (F-EVAR). It is a retrospective review of 17 patients treating 51 arteries (2.8 ± 1 per patient); 25 arteries were preserved using the Covera stent. Breakdown includes EVAR with hypogastric preservation (11.8%), B-EVAR (29.4%), F-EVAR (17.6%), chimney plus F-EVAR (11.8%) and chimney EVAR (29.4 %). This stentgraft employs a new delivery system minimizing foreshortening which may potentially lead to improved device placement accuracy. The stent has a nitinol structure lending itself to high flexibility and kink resistance, ideal for sharp angulations.

Intraoperative aneurysm occlusion was successful in 82.4% of patients; 2 gutter leaks, 1 type I endoleak, 6 type 2 endoleaks and 1 type 3 endoleak. Over the 10 ± 5-month observation period in this study, there was no evidence of target vessel occlusion. Two secondary procedures were required to address endoleak: a gutter endoleak and a type 3 endoleak in a fenestrated device.

Commentary 

The Covera stent is a new device on the market which offers alternative stent options to the Viabahn or VBX for chimney, fenestrated or branched EVARs. This retrospective study demonstrates similar success rates comparable to those in the reported literature. The flexible and kink-resistant delivery system makes this stent ideal for the extremely tortuous aorta or iliac system. While the study is limited in nature give the small sample size, retrospective nature, and short term follow-up, it does present promising results on the use of the Covera stent.

Post Author
Nicole A. Keefe, MD
Fellow, Interventional Radiology
Department of Radiology and Medical Imaging
University of Virginia
@NikkiKeefe