Partially covered stent-graft implantation in rabbit aorta: a new model to investigate bioactive stent-grafts in small animals.
OBJECTIVE
To present a new endovascular technique for placing handmade partially covered stent-grafts in rabbit aortas that is promising for experimental study of direct gene delivery to the aortic wall.


METHODS
A 7-mm-diameter Z-stent made from the inner core of a guidewire was covered with a 7-mm-diameter, 10-mm-long polyester fabric tube (2268 mL porosity). To decrease stent profile and make delivery possible through a 6-F introducer, one third of the fabric was cut away to form a partially covered polyester stent-graft. Two stent-grafts were delivered sequentially into the descending thoracic aorta of 12 male Japanese White rabbits; a third device was positioned in each aorta so that the orifices of the celiac trunk and superior mesenteric artery were not occluded.


RESULTS
The implantation was successful in 10 animals. One rabbit died during the procedure due to sheath laceration of the infrarenal abdominal aorta. Another animal died within 2 days after the procedure owing to occlusion of the celiac trunk by graft fabric. At 2 weeks, the stent-grafts in the 10 surviving rabbits remained patent, and there was no migration. Gross examination of the lumens showed that both the metal stent and the polyester graft material were completely covered with thin transparent tissue, without massive thrombosis. Histological staining revealed incomplete neointima formation between the stent-graft and the aorta. Incomplete linear endothelial cells on the luminal side of the tissue ingrowth into the stent-graft were also observed. Foreign body giant cells and macrophages represented inflammatory reactions related to the graft material.


CONCLUSIONS
Partially covered stent-grafts can be safely placed in relatively small animals and potentially used in research.
Zhong
Hongshan
H
Department of Radiology, Kanazawa University, Graduate School of Medical Science, Kanazawa City, Ishikawa, Japan. zhonghongshan@hotmail.com
Matsui
Osamu
O
Xu
Ke
K
Ogi
Takahiro
T
Okuda
Miho
M
Liu
Yi
Y
Sanada
Jun-Ichiro
J
Sun
Chuanhai
C
D000818:Animals; D001011:Aorta / Q000473:pathology / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D008297:Male; D008422:Materials Testing; D008670:Metals; D023421:Models, Animal; D011091:Polyesters; D011474:Prosthesis Design; D011817:Rabbits; D015607:Stents; D013997:Time Factors
D008670:Metals; D011091:Polyesters