Apparatus includes an elongated flexible catheter having proximal and distal
end portions, with fluidly connected coaxial lumens extending therebetween, and
a diameter sufficiently small for insertion into a patient's intraluminal passageways.
One or more treating elements are positionable within one of the lumens and movable
between the proximal and distal portions by fluid flowing through the lumens. The
distal portion includes a distal guide wire lumen having a proximal exit port distally
located relative to the treatment elements positioned at the distal portion. To
simultaneously achieve stiffness along the proximal portion and flexibility along
the distal portion, the inner and/or outer coaxial members may be of more than
one-piece construction. The inner and/or outer members may also be stepped or bumped
in diameter to decrease the pressure and fluid transit times within the catheter.
A balloon may be added to the distal portion for positioning the catheter or performing angioplasty.
