Apparatus and method for formation of foil-shaped stent struts

Abstract

A device and method is disclosed for reducing turbulent blood flow over stent struts of an intravascular stent implanted in, for example, a coronary artery. An abrasive slurry is passed over the struts of an intravascular stent in order to remove a portion of the stent struts to form an airfoil shape. When the stent having airfoil-shaped struts is implanted in an artery, the flow of blood over the airfoil shape will reduce the likelihood of turbulent blood flow and thereby will reduce the likelihood of turbulent blood flow and thereby reduce the likelihood of a buildup in plaque or injury to the vessel wall.

Description

BACKGROUND[0001]The invention relates generally to providing an apparatus for using an abrasive slurry for the removal of metal on products made from metals. More particularly, the invention relates to an apparatus for and method of using an abrasive slurry on medical devices made of titanium, stainless steel, tungsten, nickel-titanium, tantalum, cobalt-chromium-tungsten, cobalt-chromium, and the like to form a more hemodynamically compatible device.[0002]While a wide range of products or devices can be made from the listed metal alloys for use with the present invention, medical devices are particularly suitable due to the biocompatible characteristics of these alloys. Thus, for example, implantable medical devices or devices that are used within the human body are particularly suitable and can be made from these alloys that have been treated in accordance with the present invention. More particularly, and as described in more detail herein, intravascular stents can be made from th...

AI Technical Summary

Benefits of technology

The invention describes a way to improve the treatment of stents made from metal alloy. It involves using an abrasive slurry to remove parts of the stent to create an airfoil shape. This helps to reduce turbulent blood flow and improve the clinical outcome of the treatment. A chamber holds the stent stationary while the abrasive slurry flows through the stent's inner lumen. The removal of metal from the first edge of the stent results in a cross-sectional shape resembling an airfoil.

Problems solved by technology

Expandable stents, such as wire mesh, serpentine, and corrugated ring designs, for example, do not possess uniformly solid tubular walls.

A roughened outer surface may result in increased frictional obstruction during insertion and excess drag during travel to the stenotic site as well as damaging the endothelium lining of the vessel wall.

A rough finish may also cause damage to the underlying inflation balloon.

Laser cutting, however, typically is at high temperature and often leaves debris and slag material attached to the stent.

Such material, if left on a stent, would render the stent unacceptable for implantation.

Grinding, vibration, and tumbling techniques are often not suited to be employed on small detailed parts such as stents.

For example, some prior art devices have a cathode in the form of a flat plate or a triangular or single wire loop configuration, which may not yield a stent or other medical device with a smooth surface on all exposed surfaces.

For example, the prior art devices do not always provide a stent having a smooth surface on the inner tubular wall of the stent where blood flow will pass.

When implanted in an artery, the rectangular-shaped cross-section of the stent struts may produce blood flow turbulence in the artery resulting in adverse vascular reactions such as the proliferation of restenosis.

Images