Fiber tip atherectomy catheter

• US 5,009,659 A
• Filed: 10/30/1989
• Issued: 04/23/1991
• Est. Priority Date: 10/30/1989
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Schneider Electric SE
• Inventors: Tassel, Robert A. V., Hamlin, Robert N., Shockey, Rick L.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Lewis, Ralph A.
• Application Number:
  US07/428,885
• Time in Patent Office: 540 Days
• Field of Search: 604/22, 604/96, 606/159, 606/167, 606/180, 606/191, 606/194, 606/170, 128/755, 15/72, 15/104.14, 30/276
• US Class Current: 606/159
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: B08B 9/0497 provided with additional mechanical cleaning tools

Abstract

A catheter assembly especially designed for the performance of atherectomy procedures which include an elongated flexible plastic tube which can be routed through the vascular system to the location of the atheroma to be removed and a working catheter insertable through the guide catheter in the form of an elongated flexible plastic tube having a series of fibers integrally formed with or otherwise attached to the distal end portion of the working catheter and normally laying flat against the wall of the catheter. The proximal end of the working catheter is adapted for connection to a high speed motor whereby the working catheter can be rotated relative to the surrounding guide catheter. As the distal end portion of the working catheter is advanced distally beyond the end of the guide catheter, centrifugal force acts upon the fibers to cause them to extend radially outward from the core of the working catheter and when advanced against an atheroma, flail the lesion, reducing it small particles which can be aspirated out the proximal end of the catheter assembly.

Claims

1. An atherectomy catheter for removing atheromas from a blood vessel wall comprising:

(a) an elongated flexible tubular shaft having a proximal end and a distal end, said shaft including a plurality of fibers of a predetermined length with only one end of each constrained by attachment to the outer surface of said shaft and normally extending parallel thereto proximate a portion of said distal end; and

(b) means for rotating said shaft at a sufficiently high speed to cause said fibers to project radially outward of said shaft due to centrifugal force for flailing said atheroma and disintegrating same.

2. The atherectomy catheter as in claim 1 wherein said plurality of fibers are integrally formed on said shaft by forming a pattern of slits through the wall of said tubular shaft.

3. The atherectomy catheter as in claim 1 wherein said plurality of fibers comprise monofilament members of a predetermined length bonded at one end only thereof to said tubular shaft.

4. A method of conducting an atherectomy procedure comprising the steps of:

(a) advancing a balloon tipped tubular guide catheter containing a coaxially disposed and axially moveable drive tube with a cutter member attached to its distal end through the vascular system to the site of the atheroma to be treated, said cutter comprising a plurality of filaments adhered to said drive tube at only one end of said filaments;

(b) inflating the balloon on said tubular guide catheter;

(c) rotating said drive tube and cutter at a predetermined speed sufficient to cause said plurality of filaments to project radially from said drive tube while advancing said drive tube beyond the distal end of said guide catheter and into said atheroma;

(d) during step (c), applying a vacuum to the proximal end of said drive tube for aspirating blood and tissue matter through the lumen of said drive tube;

(e) deflating said balloon; and

(f) repeating steps (a) through (e) until said balloon passes completely through the atheroma.

5. An atherectomy catheter assembly comprising:

(a) a first, flexible tubular member of a predetermined outside and inside diameter having a proximal end, and distal end and a lumen extending from said proximal end to said distal end;

(b) an inflatable expander member attached to said distal end of said first tubular member to be inflated by fluid passing through said lumen of said first tubular member;

(c) a second tubular member having an outer diameter less than said predetermined inside diameter of said first tubular member, a proximal end, a distal end, and a lumen extending from said proximal end to said distal end of said second tubular member, said second tubular member being coaxially disposed within said lumen of said first tubular member with a predetermined clearance between said outer diameter of said second tubular member, allowing rotation and axial displacement of the distal end of said second tubular member beyond the distal end of said first tubular member;

(d) a cutter member attached to said distal end of said second tubular member, said cutter member including a plurality of filamentary strands having one end thereof adhered to said distal end of said second tubular member and normally extending parallel to the axis of said second tubular member;

(e) motor means coupled to said proximal end of said second tubular member for imparting rotation thereto within said lumen of said first tubular member;

(f) means coupled to said proximal end of said first tubular member for directing fluid through said lumen of said first tubular member to inflate and deflate said expander member;

(g) means for applying a negative pressure to said lumen of said second tubular member at the proximal end portion thereof; and

(h) means located at said proximal end of said second tubular member for axially extending and retracting said distal end of said second tubular and said cutter member from said distal end of said first tubular member as said second member is being rotated by said motor means, rotation of said second tubular member causing said filamentary strands to project radially from said second tubular member.