The invention provides a system, device and method for localized application of therapeutic agents within a biological conduit. A referred biological conduit comprises a blood vessel. A preferred device comprises a high-speed rotational atherectomy device having, in various embodiments, a flexible, elongate nonrotatable therapeutic agent delivery sheath having a lumen therethrough and a flexible, elongated, rotatable, drive shaft with at least one flexible eccentric enlarged abrading head disposed within lumen of the delivery sheath. The operator may actuate a controlled amount or dose of one or more therapeutic agents to release from the distal end of the delivery sheath lumen during high-speed rotation of the drive shaft. The therapeutic agent(s) is thus released into a turbulent fluidic environment resulting from high-speed rotation and orbital motion of the eccentric abrading head.
