An atherectomy device has a drive circuit which rotates a direct-current motor. The drive circuit has a three-terminal regulator having an ADJ terminal. A partial pressure resistor is connected between the ADJ terminal and an output terminal of the three-terminal regulator. Moreover, one end of six variable resistors whose resistances are set to be different from each other is connected to the ADJ terminal. The other end of the six variable resistors is selectively connected to the negative electrode of a battery by a change-over switch which is a rotary switch having six contacts. When the variable resistors are switched by the change-over switch, the output current of the three-terminal regulator becomes large. Thus, the rotation speed of a cutter which is rotated by the direct-current motor becomes high.
