Catheter with enhanced flexibility

Details Catheter with enhanced flexibility Catheter with enhanced flexibility

1999-06-30

2001-02-27

Kennedy, Sharon (Department: 3763)

Surgery

Means for introducing or removing material from body for...

Treating material introduced into or removed from body...

C604S103120, C606S194000

Reexamination Certificate

active

06193686

ABSTRACT:

BACKGROUND OF THE INVENTION
The invention relates to the field of intravascular catheters, and particularly to a catheter suitable for procedures such as angioplasty and/or stent deployment, and the like.
In percutaneous transluminal coronary angioplasty (PTCA) procedures a guiding catheter is advanced in the patient's vasculature until the distal tip of the guiding catheter is seated in the ostium of a desired coronary artery. A guidewire is first advanced out of the distal end of the guiding catheter into the patient's coronary artery until the distal end of the guidewire crosses a lesion to be dilated. A dilatation catheter, having an inflatable balloon on the distal portion thereof, is advanced into the patient's coronary anatomy over the previously introduced guidewire until the balloon of the dilatation catheter is properly positioned across the lesion. Once properly positioned, the dilatation balloon is inflated with inflation fluid one or more times to a predetermined size at relatively high pressures so that the stenosis is compressed against the arterial wall and the wall expanded to open up the vascular passageway. Generally, the inflated diameter of the balloon is approximately the same diameter as the native diameter of the body lumen being dilated so as to complete the dilatation but not overexpand the artery wall. After the balloon is finally deflated, blood flow resumes through the dilated artery and the dilatation catheter and the guidewire can be removed therefrom.
In such angioplasty procedures, there may be restenosis of the artery, i.e. reformation of the arterial blockage, which necessitates either another angioplasty procedure, or some other method of repairing or strengthening the dilated area. To reduce the restenosis rate of angioplasty alone and to strengthen the dilated area, physicians now normally implant an intravascular prosthesis, generally called a stent, inside the artery at the site of the lesion. Stents may also be used to repair vessels having an intimal flap or dissection or to generally strengthen a weakened section of a vessel or to maintain its patency. Stents are usually delivered to a desired location within a coronary artery in a contracted condition on a balloon of a catheter which is similar in many respects to a balloon angioplasty catheter, and expanded within the patient's artery to a larger diameter by expansion of the balloon. The balloon is deflated to remove the catheter and the stent left in place within the artery at the site of the dilated lesion. See for example, U.S. Pat. No. 5,507,768 (Lau et al.) and U.S. Pat. No. 5,458,615 (Klemm et al.), which are incorporated herein by reference. Thus, stents are used to keep open a stenosed vessel, and strengthen the dilated area by remaining inside the vessel. Instead of first using one catheter to dilate the body lumen and a second catheter to deploy the stent after the dilatation, the stent may be mounted on a balloon catheter and deployed at the same time the balloon is inflated to dilate the stenotic region.
Conventional balloon catheters for intravascular procedures, such as angioplasty and stent delivery, frequently have relatively stiff proximal shaft sections to facilitate advancement of the catheter within the patient's body lumen and a relatively flexible distal shaft sections to facilitate passage through tortuous anatomy such as distal coronary and neurological arteries without damage to the luminal wall. Typically, there is an intermediate shaft section or junction between the relatively stiff proximal shaft section and the relatively flexible distal shaft section which provides a transition between the proximal shaft section and less flexible than the distal shaft section.
A variety of intermediate shaft or junction designs have been utilized to provide a relatively smooth transition between the stiff proximal shaft section and the flexible distal shaft section. However, it has been difficult to develop a catheter design with an intermediate catheter shaft junction which provides a smooth transition and improved flexibility and which is also leak free when utilizing high pressure inflation fluid to inflate the balloon on the distal shaft section of the catheter for dilatation or stent deployment. The present invention satisfies these and other needs.
SUMMARY OF THE INVENTION
The invention is generally directed to an intraluminal catheter system with an improved transition between a proximal shaft section and a more flexible distal shaft section which greatly facilitates advancement through tortuous anatomy.
The intraluminal catheter of the invention has an elongated proximal shaft section which transitions to a more flexible distal shaft section through an improved intermediate shaft section disposed between the proximal and distal shaft sections. An inflation lumen extends within the catheter shaft to a location spaced proximal to the distal end. A guidewire receiving lumen extends within at least the distal shaft section of the catheter. The proximal shaft section has proximal and distal ends and a portion of the inflation lumen extending therein. The distal tip of the proximal shaft section is preferably tapered distally to smaller transverse dimensions. The distal shaft section has proximal and distal ends, a port in its distal end, at least part of the guidewire receiving inner lumen extending within the distal shaft section to the port in the distal end thereof, and at least part of the inflation lumen extending within the distal shaft section to a location proximal to the distal end of the distal shaft section. An inflatable member such as a balloon is preferably provided on the distal shaft section which has an interior in fluid communication with the inflation lumen.
The intermediate or transition shaft section which extends between the proximal and distal shaft sections is provided a tubular reinforcing member with proximal and distal ends, with part of the inflation lumen extending therein and with the proximal end of the tubular reinforcing member secured to the proximal shaft section proximal to the distal, preferably tapered tip. The distal end of the tubular reinforcing member extends into the inflation within the distal shaft section. An inner tubular support member may be disposed within the tubular reinforcing member with the proximal end receiving the distal tip of the proximal shaft section and secured thereto by an adhesive or other suitable means.
An outer polymeric jacket may be provided on the proximal shaft section which preferably extends distally from the proximal shaft section over the tubular reinforcing member. Preferably, the polymeric jacket extends beyond the distal end of the tubular reinforcing member into portion of the inflation lumen of the distal shaft section. The portion of the outer jacket which extends distally beyond the distal end of the tubular reinforcing member should taper to smaller transverse dimensions.
In one embodiment of the invention the distal shaft section has an outer tubular member and an inner tubular member with a portion of the inflation lumen being defined between the exterior of the inner tubular member and the interior of the outer tubular member. In this embodiment the proximal skirt of the balloon is secured to the distal end of the outer tubular member and the distal skirt of the balloon is secured to the distal extremity of the inner tubular member.
The inner tubular member extending within the distal shaft section has proximal and distal ends, ports in the proximal and distal ends and a guidewire receiving lumen extending therein between the proximal and distal ports. The proximal end of the outer tubular member surrounds and is secured to at least part of the intermediate shaft section. The inner tubular member preferably has a helical coil disposed therein, extending along a substantial length of the tubular member. A preferred construction includes the helical coil disposed within the wall of the inner tubular member and extending proximally within the inner tubular

Affiliated with

Also associated with

Rating

Catheter with enhanced flexibility does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Catheter with enhanced flexibility, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Catheter with enhanced flexibility will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2600039