Abstract: A catheter for performing an atherectomy procedure to remove plaque from an artery is disclosed. The catheter includes a plaque cutting head having an outer shell of thin flexible material generally cylindrical in cross-section and shaped to engage plaque in an artery. The outer shell has a plurality of openings through which the plaque will enter the shell as the shell is forced against the plaque. A cutter rotates inside the shell to cut the plaque that enters into the shell into small pieces as the catheter is pushed through an artery. A motor drive elongated drive shaft rotates the cutter.