Tantalum-Dacron coknit stent for endovascular treatment of aortic aneurysms: a preliminary experimental study

The purpose of this study was to evaluate the efficiency of intraluminal tantalum-Dacron coknit stents for the treatment of artificial aortic aneurysms in minipigs.

Replacement of the infrarenal abdominal aorta with Dacron artificial aneurysm graft was performed in eight minipigs. After 2 weeks, balloon-expandable coknit stents were inserted through the femoral artery to the site of the artificial aneurysm in seven minipigs. One animal was kept as a control. Coknit stent/artificial aneurysm complexes were explanted at various intervals from 24 hours to 12 weeks and underwent gross examination, followed by scanning electron and light microscopy studies.

Aortography performed at the time of stent placement displayed immediate exclusion of the aneurysm in every case. In follow-up studies, all coknit stents remained patent until the time of explant. Scanning electron microscopy studies revealed apparent endothelialization of the entire coknit stent lumen at and after 6 weeks.

Tantalum-Dacron coknit stents are efficient in the treatment of artificially created aneurysms in minipigs and facilitate the creation of an endothelialized new vascular wall. Clinical application of this coknit stent can be considered but necessitates retaining the same stent structure in diameters greater than 20 mm and the development of a suitable delivery system.