Intravascular deliverable stent for reinforcement of abdominal aortic aneurysm

摘要

A stent/graft especially designed to be used in a minimally invasive surgical procedure for treating an abdominal aortic aneurysm (AAA) comprises an innermost tubular structure of a length (L₁) formed by braiding a relatively few strands of shape memory alloy wire. The pick and pitch of the braid are such as to provide relative large fenestrations in the tubular wall. A portion of the innermost tubular structure of a length L₂1 is surrounded by a further braided tubular structure having relatively many strands that occlude the fenestrations of the innermost tubular structure. The composite structure can be stretched to reduce the outer diameter of the stent/graft, allowing it to be drawn into a lumen of a delivery catheter. The catheter can then be advanced through the vascular system to the site of the AAA and then ejected, allowing it to self-expand with the portion L₂ bridging the aneurysm. The portion L₁>L₂ does not block blood flow to the renal arteries while the portion L₂ prevents the aneurysm to grown and burst.