Balloon catheter and manufacturing method of balloon catheter

A method of manufacturing a balloon catheter, the balloon catheter including an inner shaft into which a guidewire is insertable, an outer shaft positioned outwardly of on an outer periphery of the inner shaft, a membranous material positioned outwardly of an outer periphery of a distal portion of the inner shaft to form a space portion between the distal portion of the inner shaft and the membranous material, and a balloon positioned outwardly of an outer periphery of the membranous material to define a lumen between the balloon and the membranous material, at least a part of the inner shaft being transformable so as to contract radially inward in response to an increase in internal pressure in the space portion, the method comprising:

• sealing one opening portion of a first tube material in a state in which a second tube material forming the membranous material is positioned inside the first tube material forming the balloon, the one opening portion of the first tube material being either a proximal opening portion at a proximal end of the first tube material or a distal opening portion at a distal end of the first tube material, the first tube material possessing an other opening portion at an end of the first tube opposite to the one opening portion;
• discharging gas between the first tube material and the second tube material via the other opening portion which is not sealed;
• sealing the other opening portion of the first tube material;
• and
• joining the first tube material and the second tube material to a shaft assembly which includes the inner shaft and the outer shaft.

A method of using a balloon catheter comprising

• inserting a balloon catheter into a living body organ, the balloon catheter comprising:
• an inner shaft that includes a guidewire lumen, an outer shaft positioned outwardly of the inner shaft, a membranous material positioned outwardly of the inner shaft, and an inflatable and deflatable balloon located outwardly of the membranous material, the membranous material possessing an inner peripheral surface and the inner shaft possessing an outer peripheral surface;
• moving the balloon catheter in the living body organ by guiding the balloon catheter along a guidewire located in the guidewire lumen to move the balloon catheter relative to the guidewire within the living body organ;
• introducing fluid into a space between the outer peripheral surface of the inner shaft and the inner peripheral surface of the membranous material to cause a portion of the inner shaft to deform inwardly into contact with the guidewire in the guidewire lumen so that the guidewire and the balloon catheter move together as a unit;
• moving the balloon catheter while the portion of the inner shaft is in contact with the guidewire to move the guidewire and the balloon catheter together and position the balloon catheter at a stenosis;
• and
• inflating the balloon into contact with the stenosis to spread out the stenosis.