Patent ID: 8500765

Claim:
A rotational atherectomy device for removing a stenotic tissue from a vessel of a patient, the device comprising: a rotatable, flexible, hollow drive shaft including a torque transmitting coil and a fluid delivery lumen coaxial with the torque transmitting coil for communicating fluid to the distal end portion of the drive shaft; an abrasive element mounted to a distal end portion of the drive shaft, the entire abrasive element extending around less than half of the circumference of the drive shaft and being fixedly positioned relative to the circumference of the drive shaft; proximal and distal inflatable counterweights fixedly positioned on the drive shaft along the distal end portion of the drive shaft such that the proximal and distal inflatable counterweights rotate together with the abrasive element in response to rotation of the drive shaft, wherein the abrasive element is positioned between and longitudinally spaced apart from the proximal and distal inflatable counterweights, wherein each of the proximal and distal inflatable counterweights is in fluid communication with the fluid delivery lumen of the drive shaft, wherein a center of mass of each of the proximal and distal inflatable counterweights is offset from the longitudinal axis of the drive shaft in a first direction while the center of mass of the abrasive element is offset from the longitudinal axis of the drive shaft in a second opposite direction; and wherein the distal end of the drive shaft includes a distal facing port, and the distal facing port of the drive shaft is adjusted from an opened condition to an occluded condition in response to fluid flow passing through the fluid delivery lumen of the drive shaft toward the distal end portion of the drive shaft.