Abstract: A balloon catheter comprises a long shaft including an inner pipe and an outer pipe, and a balloon provided at a distal end of the shaft, a distal end of the balloon being connected to the inner pipe, a proximal end of the balloon being connected to the outer pipe, and the balloon being inflated and deflated according to pressure of fluid supplied to an inside of the balloon. The balloon is molded in advance such that the balloon is inflated by pressure only to an extent in which a film of the balloon is not stretched, such that the balloon becomes a curved shape having a curved part between the proximal end and the distal end of the balloon, and such that the balloon, when deflated, is folded so as to be in a straight shape, in which the curved part is hidden, and wound around the inner pipe.

Abstract: A balloon catheter capable of expanding a narrowed site of a blood vessel in the vicinity of a curved part of the blood vessel, and of easily adapting the shape of the balloon to the shape of the curved part of the blood vessel. The balloon has a shape with a curved part, and the outer portion of the curved part (the shaded area) formed so as to have a smaller film thickness as compared with the remaining portion of the balloon is stretched by an amount larger than the remaining portion of the balloon. The difference in stretch amount between the outer portion of the curved part of the balloon and the remaining portion of the balloon becomes larger as the internal pressure of the balloon is increased. Accordingly, the extent of curve of the balloon can be controlled arbitrarily by controlling the internal pressure of the balloon.