Catheter drive apparatus having fluid delivery bearing

Claim 1

A catheter for treating a subject vessel comprising: a) an elongated flexible sheath having a center passageway and a length sufficient to extend from outside the subject to a treatment region within the subject vessel; b) a rotatable working head supported at a distal end of said sheath for abrasively treating interior walls of the vessel as the working head rotates with respect to the sheath; c) a drive shaft extending through the center passageway in the sheath and connected to the working head for transmitting motive power from outside the subject to the working head to effect rotation of the working head; and d) a bearing carried by a distal portion of the sheath for rotatably supporting the working head and defining one or more tortuous fluid flow paths between the vessel and the center passageway of the elongated flexible sheath; said bearing having an annular bearing body defining a center bore to accommodate a portion of the rotatable working head and having a flanged end portion which defines a distally facing bearing end surface; said bearing body defining one or more tortuous fluid delivery passageways each of which comprises: i) an axially extending passageway that opens into the center passageway of the elongated flexible sheath and ii) a corresponding radially extending passageway that extends radially outward from the axially extending passageway through the bearing body and opens into the vessel via a port in the bearing end surface that is at least partially exposed as the working head rotates; said port being located radially inwardly from the radial outer edge of said flanged end portion; said bearing supporting the working head in a position to simultaneously completely cover all of the axially extending passageways of the one or more tortuous fluid delivery passageways as said working head rotates.