A device and method for intravascular treatment of atherosclerotic plaque perforates the plaque with microperforations by small sharp spikes to act as serrations for forming cleavage lines or planes in the plaque. In preferred embodiments, expansion may be obtained by mechanical apparatus, expansion balloon, or balloon-assisted deployment. The plaque treatment enables a subsequent balloon angioplasty to be performed without creating substantial dissections and at low balloon pressure so as to avoid injury to the arterial wall. The plaque treatment may include dilatation of the plaque at low pressure, sufficiently that no subsequent balloon angioplasty is needed. The plaque preparation may be followed by applying one or a few ring tacks to secure the compressed plaque with minimal emplacement of foreign material.
