Tissue-removing catheter with adjustable cross-sectional dimension

Abstract

A tissue-removing catheter includes a drive shaft and a tissue-removing head. The tissue-removing head is at the distal end of the drive shaft and is configured to rotate about a longitudinal axis of the drive shaft. The tissue-removing head is selectively adjustable from an initial cross-sectional dimension to an expanded cross-sectional dimension larger than the initial cross-sectional dimension.

1 - 20 . (canceled) 
     
     
         21 . A tissue-removing catheter comprising;
 a drive shaft having opposite proximal and distal ends and configured for rotation about a longitudinal axis;   a tissue-removing head at the distal end of the drive shaft, the tissue-removing head comprising a tubular body extending along a head axis from a proximal end portion to an opposite distal end portion, the proximal end portion of the tubular body being operatively connected to the distal end of the drive shaft such that the tissue-removing head rotates with the drive shaft about the longitudinal axis, the tubular body comprising a plurality of longitudinal fingers extending along the axis from the proximal end portion of the tubular body to the distal end portion of the tubular body, a plurality of longitudinal slots being formed in the tubular body at circumferentially spaced apart locations about the head axis to separate the longitudinal fingers from one another, wherein the tissue-removing head has an initial configuration and an expanded configuration, wherein in the initial configuration of the tissue-removing head, the tubular body has a substantially constant initial cross-sectional outer dimension along the head axis from the proximal end portion to the distal end portion, and in the expanded configuration of the tissue-removing head, the longitudinal fingers are deflected to be convex along the head axis such that the longitudinal fingers define an expanded cross-sectional dimension that is greater than the initial cross-sectional dimension; and   a balloon inside the tissue-removing head and configured to be inflated to selectively adjust the tissue-removing head from the initial configuration to the expanded configuration.   
     
     
         22 . The tissue-removing catheter as set forth in  claim 21 , wherein the balloon has an expandable portion that is convex in longitudinal cross-section when the balloon is inflated. 
     
     
         23 . The tissue-removing catheter as set forth in  claim 22 , wherein the expandable portion of the balloon is arcuate in longitudinal cross-section when the balloon is inflated. 
     
     
         24 . The tissue-removing catheter as set forth in  claim 23 , wherein the expandable portion of the balloon has a proximal end and a distal end, and when the balloon is inflated, the expandable portion comprises a radial outermost point relative to the head axis that is longitudinally spaced from the proximal and distal ends of the expandable portion. 
     
     
         25 . The tissue-removing catheter as set forth in  claim 21 , wherein the balloon presses against the fingers in a radially outward direction when the balloon is inflated. 
     
     
         26 . The tissue-removing catheter as set forth in  claim 21 , wherein each of the longitudinal slots is straight along the head axis and extends radially through an entire wall thickness of the tubular body from an interior surface of the tubular body through an exterior surface of the tubular body. 
     
     
         27 . The tissue-removing catheter as set forth in  claim 21 , further comprising a control handle, the control handle including a rotary actuator for selectively rotating the driveshaft about the longitudinal axis. 
     
     
         28 . The tissue-removing catheter as set forth in  claim 21 , wherein the distal end of the drive shaft is spaced apart proximally from the distal end of the tubular body. 
     
     
         29 . The tissue-removing catheter as set forth in  claim 21 , wherein the tissue-removing head further comprises a cap connected to the distal end portion of the tubular body. 
     
     
         30 . The tissue-removing catheter as set forth in  claim 29 , wherein the cap has a proximal end and a distal end spaced apart along the head axis, the cap having a cross-sectional dimension that tapers along the head axis from the proximal end toward the distal end. 
     
     
         31 . The tissue-removing catheter as set forth in  claim 30 , wherein the cap is generally conical. 
     
     
         32 . The tissue-removing catheter as set forth in  claim 30 , wherein the cross-sectional dimension of the cap at the proximal end of the cap is the same as the initial cross-sectional dimension of the tubular body. 
     
     
         33 . The tissue-removing catheter as set forth in  claim 21 , wherein the tubular body is formed from one of nitinol and spring steel. 
     
     
         34 . The tissue-removing catheter as set forth in  claim 21 , wherein the drive shaft has a cross-sectional dimension, the initial cross-sectional dimension of the tubular body being about the same as the cross-sectional dimension of the drive shaft. 
     
     
         35 . The tissue-removing catheter as set forth in  claim 21 , wherein the tissue-removing head comprises abrasive grit on an exterior of the tissue-removing head. 
     
     
         36 . The tissue-removing catheter as set forth in  claim 21 , wherein the balloon is connected with the driveshaft such that the balloon rotates with the drive shaft about the longitudinal axis. 
     
     
         37 . The tissue-removing catheter as set forth in  claim 21 , wherein in the expanded configuration of the tissue-removing head, the longitudinal fingers are deflected to have a generally parabolic shape. 
     
     
         38 . The tissue-removing catheter as set forth in  claim 21 , wherein in the expanded configuration of the tissue-removing head, the longitudinal fingers are deflected to be generally arcuate. 
     
     
         39 . The tissue-removing catheter as set forth in  claim 21 , wherein in the expanded configuration of the tissue-removing head, each longitudinal finger has a vertex at about a midpoint along a length extending along the head axis between the proximal end portion and the distal end portion of the tubular body. 
     
     
         40 . The tissue-removing catheter as set forth in  claim 39 , wherein in the expanded configuration of the tissue-removing head, each longitudinal finger slopes radially inward along an entire proximal segment extending from the vertex to the proximal end portion of the tubular body along the head axis and slopes radially inward along an entire distal segment extending from the vertex to the distal end portion of the tubular body along the head axis.