The invention relates to an intravascular rotary
cutting device which comprises a sheathing canal, a rotating shaft, a
tool bit assembly and a
handle. The cutter head
assembly comprises a first rotary cutter and a second rotary cutter, the second rotary cutter is provided with an arched structure, the arched height of the second rotary cutter can be increased or decreased under the action of external force, so that the second rotary cutter has a variable
cutting diameter in a working state, the
cutting diameter is not restrained by the inherent size of the sheathing canal any more, and the minimally invasive approach is kept while the cutting
diameter is increased. A larger effective lumen and a better tissue treatment capability can be realized; in a non-working state, the device can be retracted into the sheath tube, so that the damage to the
blood vessel is reduced; the
handle comprises a shell, a rotary cutting driving
assembly and a telescopic driving assembly; the near end of the sheathing canal or the shell is of a detachable sectional type structure, by means of the design of the detachable sectional type sheathing canal or the shell, the cutter head assembly and the rotating shaft can be independently withdrawn, meanwhile, a complete instrument channel is reserved, follow-up examination or treatment instruments can be directly introduced, and the whole
system does not need to be completely withdrawn from the
human body.