[Treatment of an abdominal aorta aneurysms with endovascular stent grafts and embolizing materials: an experimental...

To create an animal model to stabilize the aneurysmal sac and prevent type II leaks in the endovascular treatment of aneurysms of the abdominal aorta (AAA) by placing an endoprosthesis (stent-graft) and filling the aneurysmal sac.

AAA were experimentally induced in pigs and sheep; AAA were subsequently treated with endovascular stent grafts and stabilized in the same procedure by introducing ethibloc and onyx through a vascular catheter placed within the aneurysmal sac. All animals underwent aortography, and MR angiography and abdominal CT were performed on randomly selected animals. Histological studies included both macroscopic and microscopic examination. Two sheep were analyzed one year after the procedure. We evaluated the characteristics of the materials employed, their diffusion in the collateral arteries, and their efficacy in stabilizing the aneurysmal sac.

The procedure was successfully carried out in all animals. Survival in the pigs was 100 %, whereas greater instability under anesthesia in the sheep led to 50 % perioperative mortality. Both ethibloc and onyx were considered easy to use and stable over time.

The sac of an AAA treated with an endovascular stent graft and its collateral vessels can be treated in the same procedure with materials introduced through a catheter.