The disclosure provides plaque treatment catheter assemblies for the treatment of arterial plaques and removal of clots. One assembly includes a second catheter tube movable within a first catheter tube, and an expansion member movable within the second tube. The second catheter tube has one or more distally-disposed and outwardly-expandable plaque treatment portion(s). Another assembly includes a catheter tube and at least one channel(s) within the catheter. The channel includes an elongate member with a distally-disposed plaque scoring or clot retrieval member. Optionally, the assembly includes an expandable member that can cause movement of the scoring member.