Device for cutting tissue

An atherectomy catheter comprising:

• a rotatable shaft;
• a cutting element coupled to the rotatable shaft and configured to rotate the cutting element about an axis of rotation, the cutting element having
• an annular cutting edge,
• an interior surface radially inward of the annular cutting edge, and
• a raised element comprising first, second and third walls extending from the interior surface of the cutting element, wherein the first and third walls extend generally radially relative to the axis of rotation from adjacent the annular cutting edge toward the axis of rotation, wherein the second wall is radially inward of the first and third walls and extends between and connects the first and third walls, wherein the first wall curves toward the third wall from the second wall toward the annular cutting edge to direct cut particles of material toward the axis of rotation of the cutting element.