Stent and method for manufacturing the stent

Abstract

A method for manufacturing a helical stent includes the steps of providing a stent body with struts disposed about the circumference thereof in turns and with bridges connecting the struts in adjacent turns. The stent body is at least partially expanded and, some time during expansion, some of the bridges, in particular, sacrificial bridges, are removed. A method for implanting this stent includes loading the stent at a stent delivery system, traversing the stent at the delivery system to an implantation site, and implanting the stent at the implantation site.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the priority, under 35 U.S.C. § 119, of U.S. Provisional Patent Application No. 60 / 606,261 filed Sep. 1, 2004, the entire disclosure of which is hereby incorporated herein by reference in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] n / aFIELD OF THE INVENTION [0003] The invention lies in the field of vascular stents. In particular, the invention is in the field of helical stents for peripheral arteries, the biliary tree, and other body lumens. [0004] Stents have been developed for use in various lumens of the body, including the biliary tree, venous system, peripheral arteries, and coronary arteries. Stents are used to open or hold open a lumen that has been blocked (occluded) or reduced in size (stenosed) by some disease process, such as atherosclerosis or cancer. Previously developed stents for use in the biliary, venous, and arterial systems have been of two broad classes: ...

AI Technical Summary

Benefits of technology

The present invention provides a helical stent and a method for manufacturing it that overcomes the disadvantages of previous stents. The stent has shorter struts and a higher number of struts around its circumference, which makes it more flexible and better suited for use in arteries and other body lumens. The stent can be expanded using a balloon or allowed to self-expand, and it can be used in the treatment of peripheral arteries, biliary tree, and other body lumens. The stent can also be coated with drugs or other therapies to reduce restenosis or other complications. The method for manufacturing the stent involves removing some of the bridges that connect the struts in adjacent turns. The stent can be compressed onto a balloon catheter or retained in a compressed state for delivery to an implantation site. The stent can have a diameter of between 4 mm and 12 mm and a length of between 10 mm and 250 mm. The stent can be implanted in a blood vessel and its expansion is controlled to retain its original shape. The invention provides a helical stent with improved flexibility and a higher number of struts that can be used to treat peripheral arteries and other body lumens.

Problems solved by technology

Other manufacturing techniques have been proposed, such as vacuum or chemical deposition of material or forming a tube of machined flat material, but those “exotic” methods have not been widely commercialized.

However, Palmaz teaches use of a stent that is very difficult to manufacture because of the great number of very small openings in the covering film or “web.”

Because prior art stent designs have large gaps between stent parts, drug elution about these parts does not adequately cover all of the tissue within the bounds of the stent.

In his report “Era of Drug-Coated and Drug-Eluting Stents” (TCT 2002), G. Grube states that the typical open-cell configuration gives poor distribution of the drug into the arterial wall because of the large open gaps when the stent is situated in a bend of the artery.

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