IMPLANTABLE MEDICAL DEVICE

摘要

A stent graft includes a tubular graft element to which there are attached a plurality of stent rings. The stent rings are formed of a plurality of stent struts arranged in a zig-zag arrangement with alternating peaks and valleys. The end-most stent is located at the proximal end of the graft tube. Between adjacent peaks of the end most stent, there is provided a series of bridging elements. These are preferably formed of Nitinol wire and to be substantially more flexible than the stent struts. The bridging elements extend in the region of graft material between adjacent stent peaks and are attached to the graft material, for example by suturing. The bridging elements are substantially more flexible than the stent ring and therefore impart little opening force on the graft material in comparison to the force produced by the stent ring. However, the bridging elements impart enough force on the flaps of graft material between the peaks of the stent ring keep these flaps open, that is against the vessel wall. The bridging elements can provide integral barbs.

主权项

1. An implantable medical device including:
a tubular graft member; at least one stent provided on the graft member proximate an end thereof, wherein the stent is formed of a plurality of struts coupled together at their ends in the form of a stent ring having peaks and valleys, the struts of the stent being formed of a flexible material to allow the stent to be compressed and to expand, wherein the struts have a first flexibility; and a plurality of bridging elements located between adjacent peaks formed by the struts of said stent, said bridging elements being coupled to the struts and extending towards and proximate said end of said graft element; said bridging elements having a second flexibility, wherein second flexibility is greater than said first flexibility; wherein said bridging elements produce in use an expansion force urging graft material of said graft element in a graft opening direction, wherein the opening force produced by said bridging elements is less than an opening force produced by said stent ring.