Stent delivery assembly

A stent delivery assembly comprising:

• a catheter including a shaft having a proximal end and a distal end, and a balloon provided closer to the proximal end than the distal end on the shaft;
• and
• a stent having a tubular shape, and coupled to the balloon to surround an outer circumferential surface of the balloon,
• wherein the balloon includes a main body having a first end and a second end,
• the stent is located to be biased towards the first end, such that the main body of the balloon includes a preferential inflation region that is not surrounded by the stent in a region between the second end and the stent and a delayed inflation region surrounded by the stent,
• the main body is formed to extend in an uninflated state with a single inner space having a diameter that is constant from the first end to the second end,
• in a process in which the balloon is inflated, a portion of the stent surrounding a distal end of the delayed inflation region close to the preferential inflation region is inflated to form a tapered shape portion by a force caused when the preferential inflation region of the balloon is preferentially inflated as compared to a proximal end of the delayed inflation region of the balloon subjected to resistance to inflation,
• a length of the preferential inflation region is within a range of 3 mm to 6 mm, and
• an initial angle of the tapered shape portion is inclined within a range of 39° to 43° from a central axis of the catheter.

A stent delivery assembly comprising:

• a catheter including a shaft having a proximal end and a distal end, and a balloon provided closer to the proximal end than the distal end on the shaft;
• and
• a stent having a tubular shape, and coupled to the balloon to surround an outer circumferential surface of the balloon,
• wherein the balloon includes a main body having a first end and a second end,
• the stent is located to be biased towards the first end, such that the main body of the balloon includes a preferential inflation region that is not surrounded by the stent in a region between the second end and the stent and a delayed inflation region surrounded by the stent,
• the main body is formed to extend in an uninflated state with a single inner space having a single diameter that is constant from the first end to the second end,
• the shaft includes a lumen communicating with the single inner space,
• in a process in which the balloon is inflated by a fluid supplied into the single inner space through the lumen, a portion of the stent surrounding a distal end of the delayed inflation region close to the preferential inflation region is inflated to form a tapered shape portion by a force caused when the preferential inflation region of the balloon is preferentially inflated as compared to a proximal end of the delayed inflation region of the balloon subjected to resistance to inflation,
• a length of the preferential inflation region is within a range of 3 mm to 6 mm, and
• an initial angle of the tapered shape portion is inclined within a range of 39° to 43° from a central axis of the catheter.