Rotational Atherectomy Device

Abstract

A rotational atherectomy device for removing a stenotic tissue from a vessel of a patient is disclosed. The device comprises a rotatable, flexible, hollow drive shaft having a fluid impermeable wall defining a lumen of the drive shaft and, an abrasive element mounted to a distal end portion of the drive shaft proximal to and spaced away from a distal support element formed at a distal end of the drive shaft. The distal support element is inflatable by pressurized fluid which flows in an antegrade direction through said lumen of the drive shaft and is least partially re-directed into the distal fluid inflatable support element. The distal fluid inflatable support element has an outer wall comprising an outflow opening.

1 . (canceled) 
     
     
         2 . A system for performing rotational atherectomy to remove stenotic lesion material from a blood vessel of a patient, the system comprising:
 an elongate drive shaft sheath defining a sheath lumen therethrough, the drive shaft sheath being configured to be at least partially disposed within the blood vessel; and   a rotational atherectomy device slidable through the elongate drive shaft sheath toward stenotic lesion material in a blood vessel, comprising:
 an elongate flexible drive shaft including: a torque-transmitting coil along a first portion of the drive shaft and extending to a distal portion of the drive shaft, and a fluid impermeable layer exposed along an exterior circumferential region of at least the distal portion of the drive shaft, wherein the first portion of the drive shaft is configured to be at least partially disposed within the sheath lumen while the distal portion of the drive shaft extends distally of the sheath lumen when the system is used for performing the rotational atherectomy, wherein the torque-transmitting coil is exposed along an exterior circumferential region of the first portion of the drive shaft when the system is used for performing the rotational atherectomy; 
 an eccentric abrasive element mounted to the distal portion of the drive shaft such that a center of mass of the eccentric abrasive element is offset from the longitudinal axis of the drive shaft, wherein the eccentric abrasive element comprises: an abrasive outer surface, and a mounting portion that wraps circumferentially around the distal portion of the drive shaft so that the abrasive outer surface is fixedly positioned relative to the distal portion of the drive shaft; and 
 a first coaxial stability element that is fixed to the distal portion of the drive shaft and that has a center of mass coaxial with the longitudinal axis, the first coaxial stability element being distally spaced apart from the eccentric abrasive element wherein rotation of the torque-transmitting coil about the longitudinal axis drives simultaneous rotation of the eccentric abrasive element and the first coaxial stability element about the longitudinal axis. 
   
     
     
         3 . The system of  claim 2 , wherein the drive shaft and fluid impermeable layer extend distally beyond the eccentric abrasive element. 
     
     
         4 . The system of  claim 2 , further comprising a second coaxial stability element that is fixed to the drive shaft and that has a center of mass coaxial with the longitudinal axis, the second stability element being proximally spaced apart from the eccentric abrasive element. 
     
     
         5 . The system of  claim 4 , wherein the first and second coaxial stability elements comprise inflatable stability elements. 
     
     
         6 . The system of  claim 4 , wherein the first and second stability coaxial elements are equally spaced apart from the eccentric abrasive element. 
     
     
         7 . The system of  claim 2 , further comprising a guidewire configured to be slidably withdrawn from the drive shaft. 
     
     
         8 . The system of  claim 2 , wherein the rotational atherectomy device comprises a proximal end configured to be connected to a handle assembly for both rotating and longitudinally moving the drive shaft. 
     
     
         9 . The system of  claim 2 , wherein the eccentric abrasive element defines a slot. 
     
     
         10 . The system of  claim 9 , wherein the mounting portion of the eccentric abrasive element comprises a strap which extends through said slot and is connected to the drive shaft. 
     
     
         11 . The system of  claim 2 , wherein the eccentric abrasive element has a leading edge and a trailing edge relative to a rotational direction of the drive shaft, the leading edge of the abrasive element being thinner than the trailing edge. 
     
     
         12 . The system of  claim 2 , wherein the eccentric abrasive element comprises a solid body defining the abrasive outer surface and extending around less than half of the circumference of the drive shaft. 
     
     
         13 . The system of  claim 2 , wherein the drive defines a central lumen that is surrounded by the fluid impermeable layer. 
     
     
         14 . The system of  claim 2 , the first coaxial stability element is fixedly positioned at a distal tip of the drive shaft. 
     
     
         15 . The system of  claim 2 , wherein the first coaxial stability element comprises an inflatable stability element. 
     
     
         16 . The system of  claim 2 , wherein the drive shaft comprises a closable valve positioned proximate to a distal end of the drive shaft.