Coil bioabsorbable stents

摘要

An expandable, bioabsorbable stent having a coiled-coil configuration is described. The stent further comprises regions of variable pitch that allow for variation in either rigidity, or variability diameter within sub-regions along the length of the deployed stent. By varying the diameter allows the stent to extend into regions such as branched vessels, or into the neck of aneurysms. In some embodiments, the stent comprises longitudinal support fibers that run substantially the length of the deployed stent to provide additional strength. In addition, the stent may also comprise regional support fibers that run less than the length of the stent, and which provide increased regional strength while permitting flexibility of the stent. The stent further comprises micro-tubes that are configured to be visible using medical imaging techniques. The stent can be manufactured from materials that are bioabsorbable and/or include the ability to release pharmacologically active substances over time.

主权项

1. An expandable stent comprising:
a single filament shaped into a primary coil having a plurality of primary coil segments that each include a plurality of elements, the stent having a first diameter when the stent is in a furled configuration; a plurality of longitudinal support fibers coupled to the filament, wherein at least one longitudinal support fiber is disposed along an outer aspect of the stent and is parallel to a major axis of the stent and extends along the entire length of the stent; wherein at least one of the elements is expandable beyond others of the elements and arranged such that upon expansion of the elements the stent assumes an unfurled configuration having two distinct diameters at two distinct primary coil segments, and wherein the first diameter is smaller than the two distinct diameters; and wherein at least another one of the longitudinal support fibers is discontinuous at a location between the two distinct primary coil segments to allow formation of a localized zone of increased radius or curvature along a longitudinal axis of the stent.