Radially expandable polymer prosthesis and method of making same

摘要

Polymeric stents having fracture toughness and resistance to recoil after deployment are disclosed along with methods of manufacturing such stents. Improvements to mechanical characteristics and other improvements may be achieved by having polymer chains within individual stent struts oriented in a direction that is closer to or in line with the axis of the individual stent struts. The struts are connected to each other by hinge elements that are configured to bend during crimping and deployment of the stent. Ring struts form ring structures. A ring structure can have an overall curvilinear length from about 12 mm to about 15 mm.

主权项

1. An endoprosthesis comprising:
a tubular network of struts cut from a radially expanded PLLA polymer tube, the tubular network comprising W-shaped closed cells, each W-shaped closed cell abutting six other W-shaped closed cells, each W-shaped closed cell comprising ring struts, link struts, U-shaped hinge elements, and Y-shaped hinge elements, the ring struts forming a plurality of ring structures, each ring structure connected to another one of the ring structures by at least one link strut, each U-shaped hinge element connecting exactly two ring struts to each other, the U-shaped hinge element being tangent to the two ring struts, each Y-shaped hinge element connecting a link strut to exactly two ring struts, wherein the tubular network has an outer diameter of about 3.5 mm and is configured to be crimped to an outer diameter of about 1.3 mm and expanded to an outer diameter of about 3.8 mm without substantial damage to the U-shaped hinge elements, and wherein each ring structure has an overall curvilinear length from about 12 mm to about 15 mm, and the overall curvilinear length for each ring structure is measured along an imaginary curve that runs continuously through the center of the linear ring struts and the hinge elements of the ring structure.