Provided is a biodegradable stent comprising a magnesium alloy free of a rare earth element and aluminum. The stent comprises: a core structure comprising a magnesium alloy containing 90 wt % or more of magnesium as a main component, and zinc, zirconium, and manganese as accessary components, the magnesium alloy being free of a rare earth element and aluminum; a first corrosion resistant layer formed on the core structure and containing magnesium fluoride as a main component; and a second corrosion resistant layer formed on the first corrosion resistant layer and comprising a parylene. A method for producing such a bioabsorbable stent is also provided.

An implantable stent includes multiple circumferential segments that surround a bore and are connected in series along a length to form a tubular wall. Multiple adjacent alternating opposite facing crowns arranged along each segment's circumference are bridged by struts. The struts include a series of staggered arcuate edges with limited flats to provide a limited region of maximum width between significantly extended reducing diameter tapers at either end where they transition into the crowns. Connections between adjacent segments are wider and stiffer than the struts and strut-crown transitions in the segments. The crowns include inner and outer radii with off-set centers along a common axis to provide medial crown peaks along the axis that are wider than the narrowed crown shoulders on either side of the axis and from which the tapered struts extend. Material strain and flexure along the stent during lateral bending is distributed mainly within the segments, e.g. along the struts or crowns, versus at the connections between segments. Material strain and deformation during radial expansion is principally concentrated at the crown shoulders and tapered transition region with the struts. Particular closed-open-closed arrangements along the stent length are disclosed, though with fewer stent connections in the relatively closed end-portions along the stent than are provided by other typically open cell stents in prior use. Enhanced combinations of performance characteristics are provided regarding visibility, trackability, expansion characteristics, fatigue failures, coating integrity, and local drug delivery from the stent.

An implantable medical device that is fabricated from materials that present a blood or body fluid or tissue contact surface that has controlled heterogeneities in material constitution. An endoluminal stent-graft and web-stent that is made of a monolithic material formed into differentiated regions defining structural members and web regions extending across interstitial spaces between the structural members. The endoluminal stent-graft is characterized by having controlled heterogeneities at the blood flow surface of the stent.

A vascular stent, including a plurality of wave-shaped supporters connected in an axial direction. The tubular stent includes a proximal support mechanism, a middle support mechanism, and a differential support mechanism connected in sequence; the middle support mechanism and the distal support mechanism are respectively closed-loop structure; the proximal support mechanism includes a first support portion connected to the middle support mechanism and a second support portion provided at the proximal end of the first support portion; the first support portion is a closed-loop structure; the second support portion is an open-loop structure, and the end surface of the proximal end of the second support portion is an uneven structure to provide local support in the circumferential direction.

A stent that has a reduced state, an expanded state, and a delivery state, includes helical windings, a bridge, and a sacrificial bridge. The helical windings define a cylinder with a helical axis including a strut having a straight portion connected to a curved portion, wherein the straight portion aligns with the helical axis. The bridge connects adjacent windings. The sacrificial bridge connects adjacent windings and is configured for removal in the expanded state.

Self-expending stents that include circumferential rings of alternating interconnected struts connected by flexible connectors. The struts of the rings and flexible connectors have a structure, including areas of expanded or reduced width or thickness, to account for venous applications. When used for venous applications, the stents convey benefit from configurations that improve flexibility (due to the greater elasticity of venous applications) while maintaining enough stiffness to resist pressure on the venous structure in selected areas (such as for the May-Thurner syndrome). The stents include particular structural characteristicsoften expressed as ratios between different measurementsthat are particularly advantageous for (although not limited to) venous applications.

A stent device includes generally cylindrical rings aligned along a longitudinal axis, and interconnected by interconnecting members. Each interconnecting member includes a first coupling end, a second coupling end, and an elongate portion therebetween. The first coupling end, the elongate portion, and the second coupling end combine in either a first orientation or a second orientation, which are substantially mirror images. For each interconnecting member, the first coupling end can intersect with a midpoint of a transition region of a substantially repeating curved segment on one of the rings, and the second coupling end can intersect with a midpoint of a curved segment of a different and immediately adjacent ring. The interconnecting members can be arranged in rows extending longitudinally along the device. Along each row, consecutive interconnected members alternate between the first orientation and the second orientation. A cover may be provided over the stent device.

Examples of a stent are provided with interlocking joints removably coupling adjacent axial stent segments. Mating elements forming the interlocking joints maintain engagement when the stent is in the radially compressed configuration, for example, during tracking of the stent to a treatment site of a body vessel, and become disengaged during radial expansion of the stent. When disengaged, the disconnected the axial stent segments remain discrete stent structures separated from one another along the point of treatment.

This disclosure relates to a stent for use in vascular interventions, the stent comprising a first portion for placing in a first lumen and a second portion for placing in a region of a branch point at which the first lumen branches off a second lumen, the second portion comprising one or more rings linked by second links to the first portion and, if the second portion comprises two or more rings, together. The first and second portions are configured to be different to facilitate controlled longitudinal deformation of the second portion.

Various stents and stent-graft systems for treatment of medical conditions are disclosed. In one embodiment, an exemplary stent-graft system may be used for endovascular treatment of a thoracic aortic aneurysm. The stent-graft system may comprise proximal and distal components, each comprising a graft having proximal and distal ends, where upon deployment the proximal and distal components at least partially overlap with one another to provide a fluid passageway therebetween. The proximal component may comprise a proximal stent having a plurality of proximal and distal apices connected by a plurality of generally straight portions, where a radius of curvature of at least one of the proximal apices may be greater than the radius of curvature of at least one of the distal apices. The distal component may comprise a proximal z-stent coupled to the graft, where the proximal end of the graft comprises at least scallop formed therein that generally follows the shape of the proximal z-stent. Further, the distal component may comprise at least one z-stent stent coupled to the distal end of the graft and extending distally therefrom that reduces proximal migration of the distal component.