Impact of graft material configuration on stent-graft endoleak in vitro.
OBJECTIVE
To assess the effect of different attachment patterns between graft materials and stents on type I endoleak.


METHODS
Nitinol stents were covered with a coating of Tegaderm in either a straight-edged pattern across the stent cells or a contoured zigzag pattern conforming to the stent skeleton's honeycomb-shaped cells. The stent-grafts were deployed in an ex vivo circuit across a gap of tubing to simulate an aneurysm cavity. Fluid leaking from the gap for more than 30 minutes was recorded as endoleak. Two contoured attachment patterns (short and long necks) and four straight-edged patterns with necks of varying length were tested. Each experiment was repeated 15 times.


RESULTS
The length of the aneurysm neck covered by the graft material was inversely related to the rate of endoleak. The zigzag pattern of graft attachment demonstrated significantly less endoleak than the straight-edged pattern in the setting of a short aneurysm neck (0.25 mL vs 47.3 mL).


CONCLUSIONS
Adopting the contoured (zigzag) attachment of graft material to stents minimizes endoleak in vitro, particularly in the setting of a short aneurysm neck.
Leigh
L
L
Department of Radiology, Beth Israel Deaconess Medical Center-West Campus, 330 Brookline Avenue, Boston, Massachusetts 02215, USA.
Rabkin
D
D
Berbaum
K
K
Vrachliotis
T G
TG
Brophy
D P
DP
Lang
E V
EV
D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D006801:Humans; D066298:In Vitro Techniques; D008955:Models, Cardiovascular; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011673:Pulsatile Flow; D015607:Stents