Balloon Catheter

Abstract

A balloon catheter includes a balloon/shaft assembly and a linear member. The balloon/shaft assembly includes a catheter shaft extending from a proximal end to a distal end and a balloon connected to the catheter shaft. The linear member straddles an inflatable region of the balloon and is mounted on the balloon/shaft assembly. The linear member includes a hard portion and a flexible portion. The hard portion includes at least an outer portion disposed on an opposite side to an inner portion facing the inflatable region, of a portion disposed along an outer peripheral surface of the inflatable region in an inflated state. The flexible portion is a portion other than the hard portion. The flexible portion is extendable and has a lower hardness than the hard portion.

What is claimed is: 
     
         1 . A balloon catheter comprising:
 a balloon/shaft assembly that includes a catheter shaft extending from a proximal end to a distal end and a balloon connected to the catheter shaft, the balloon having an inflatable region configured to inflate outward in a radial direction around the catheter shaft; and   a linear member straddling the inflatable region of the balloon and being mounted on the balloon/shaft assembly at a distal end position located further toward a distal end side than the inflatable region and at a proximal end position located further toward a proximal end side than the inflatable region,   wherein the linear member includes:
 a hard portion that includes at least an outer portion disposed on an opposite side to an inner portion facing the inflatable region, of a portion disposed along an outer peripheral surface of the inflatable region in an inflated state, and 
 a flexible portion that is a portion other than the hard portion, the flexible portion being extendable and having a hardness lower than the hard portion, 
   wherein the flexible portion extends between the distal end position and the proximal end position,   wherein the hard portion protrudes to the outside from the outer portion of a portion of the flexible portion that is disposed along the outer peripheral surface of the inflatable region in the inflated state, and   wherein, a thickness of a portion of the flexible portion, which is located further toward the distal end side than the hard portion, is narrower than a thickness of a portion of the flexible portion located further toward the proximal end side than the hard portion.   
     
     
         2 . The balloon catheter according to  claim 1 , wherein a slit is formed extending toward the inside in the radial direction from an end portion on the outside of the hard portion. 
     
     
         3 . The balloon catheter according to  claim 1 , wherein a direction extending to the outside along a distal end portion is inclined toward a proximal end side, the distal end portion being an end portion on the distal end side of the hard portion. 
     
     
         4 . The balloon catheter according to  claim 1 , wherein a direction extending to the outside along a proximal end portion is inclined toward the distal end side, the proximal end portion being an end portion on the proximal end side of the hard portion. 
     
     
         5 . The balloon catheter according to  claim 1 , wherein
 a first direction extending to the outside along a distal end portion is inclined toward the proximal end side, the distal end portion being an end portion on the distal end side of the hard portion,   a second direction extending to the outside along a proximal end portion is inclined toward the distal end side, the proximal end portion being an end portion on the proximal end side of the hard portion, and   an angle of the first direction with respect to an extending direction of the catheter shaft is smaller than an angle of the second direction with respect to the extending direction of the catheter shaft.   
     
     
         6 . The balloon catheter according to  claim 2 , wherein the slit is a notch where a part of the linear member is cut out. 
     
     
         7 . The balloon catheter according to  claim 2 , wherein the slit is an incision having two surfaces that face each other and are in contact with each other. 
     
     
         8 . The balloon catheter according to  claim 1 , wherein at least a part of the flexible portion of the linear member is bonded to the balloon. 
     
     
         9 . The balloon catheter according to  claim 1 , wherein the linear member is disposed along an outer peripheral surface of the balloon in the inflated state. 
     
     
         10 . The balloon catheter according to  claim 1 , wherein
 two radiopaque markers are respectively provided in two positions separated from each other in an extending direction of the catheter shaft,   of the two radiopaque markers, a position of a marker provided on the distal end side corresponds to a position of a boundary of the inflatable region on the distal end side, in the extending direction of the catheter shaft, and   of the two radiopaque markers, a position of a marker provided on the proximal end side corresponds to a position of a boundary of the inflatable region on the proximal end side, in the extending direction of the catheter shaft.   
     
     
         11 . The balloon catheter according to  claim 1 , wherein
 the balloon includes a proximal end side leg portion bonded to the catheter shaft at a position further toward the distal end side than the proximal end position, and   an end portion on the proximal end side of the linear member is bonded to the balloon/shaft assembly at the proximal end position.   
     
     
         12 . The balloon catheter according to  claim 1 , wherein
 the balloon includes a proximal end side leg portion bonded to the catheter shaft at the proximal end position, and   an end portion on the proximal end side of the linear member is bonded to an outer peripheral surface of the proximal end side leg portion.   
     
     
         13 . The balloon catheter according to  claim 1 , wherein the linear member is formed of a synthetic resin. 
     
     
         14 . The balloon catheter according to  claim 1 , wherein the linear member includes end portions in an extending direction, at least one of the end portions being connected to the catheter shaft. 
     
     
         15 . The balloon catheter according to  claim 1 , wherein the thickness of the portion of the flexible portion located further toward the distal end side than the hard portion is constant.