Catheter with irregular inner and/or outer surfaces to reduce travelling friction

A finished reinforced catheter made from a polymeric material and having a bore with an inner diameter and an outer diameter with a first reinforcement member wound in a first rotational direction to form a first helix and a second reinforcement member wound in a second helix in a second rotational direction which is opposite to said first rotational direction to form a second helix, said first and second reinforcement members being completely embedded within the wall of said catheter between said inner diameter and said outer diameter, said first reinforcement member being embedded sufficiently close to said inner diameter as to provide at least a ridge interrupting the smoothness of said inner diameter and following the contour of the reinforcement material located adjacent thereto, said ridge defining a land having an effective I.D. less than an actual I.D. of said interior diameter, so that when used as a guiding catheter, the effective friction force on an axially inserted or rotated concentric catheter is less than that exhibited by a smooth I.D. wall.