Moderate calcification will be defined as radiopaque density observed only during the cardiac cycle and typically involving only one side of the vascular wall, and severe calcification will be defined as radiopaque density noted without cardiac motion prior to contrast injection and involving both sides of the arterial wall. After completion of diagnostic angiogram and confirmation of subject eligibility, subjects will be randomly assigned to Rotational Atherectomy (RA) or Cutting Balloon Angioplasty (CBA)/Percutaneous Transluminal Coronary Angioplasty (PTCA) group in a 1:1 fashion.