Guidewire-Centering Catheter Tip

Abstract

A catheter for use with a guidewire, the catheter having a distal tip that centers the guidewire even when the catheter is severely bent, thereby avoiding protrusion of the distal tip of the catheter at the outer meridian of the catheter bend and reducing the risk of the catheter tip catching on the luminal surface of the adjacent vasculature. The distal tip of the catheter incorporates at least one guidewire bearing, preferably multiple bearings in the form of longitudinally oriented ribs, which provide the centering characteristic with minimal friction between the inner surface of the catheter distal tip and the outer surface of the guidewire. Preferably, at least four guidewire bearings are provided.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation of co-pending U.S. patent application Ser. No. 10 / 324,714 filed Dec. 19, 2002 (allowed).FIELD OF THE INVENTION[0002]The present invention relates to the field of catheters intended for use with guidewires, and more particularly to the distal tip of such catheters.BACKGROUND OF THE INVENTION[0003]Catheters intended for use with guidewires have a distal tip with an inner diameter that is slightly larger than the outside diameter of the intended guidewire. The difference in diameter is necessary to provide the guidewire with operating clearance. When navigating tortuous anatomy or crossing a previously deployed stent, the guidewire is not concentric with the distal tip of the catheter due to this required clearance. Because of this required clearance, the distal tip of the catheter protrudes along the outer meridian of a severely bent catheter / guidewire assembly, with the result that it is at risk of catchi...

AI Technical Summary

Benefits of technology

The present invention is about a centering means provided to the distal tip of a catheter to ensure that a guidewire or other device exiting the distal tip is substantially centered with respect to the distal tip. This reduces the risk of the edge of the catheter tip catching on the luminal surface of a vessel when the tip region of the catheter is severely bent, as is often the case when traversing tortuous vessels with the catheter. The centering means comprises at least one and preferably multiple bearing surfaces located on the luminal surface of the catheter tip. These bearing surfaces take the form of ribs that project inwardly from the luminal surface of the catheter tip. The ribs are preferably oriented substantially parallel to the longitudinal axis of the catheter. The bearings can be of a minimal interference with the guidewire or other device, and they are preferably of a short length to ensure optimal centering. The catheter tip of the present invention can be used with any catheter that is placed with a guidewire of any size.

Problems solved by technology

Because of this required clearance, the distal tip of the catheter protrudes along the outer meridian of a severely bent catheter / guidewire assembly, with the result that it is at risk of catching on the vessel wall and consequently impede trackability of the catheter over the guidewire.

This can result in an increase in the time of the procedure as the medical practitioner may be forced to withdraw the catheter and again attempt to maneuver the assembly through the tortuous anatomy responsible for the severe bend.

Likewise, if the catheter tip catches on the luminal surface of the vessel wall, damage to the luminal surface may result, requiring surgical intervention.

Similarly, the catheter tip is also at risk of catching on the struts at the end of a previously deployed stent, thereby impeding crossability.

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