Rotational atherectomy device with fluid inflatable support elements and two torque transmitting coils

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 fluid impermeable 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 being inflatable by pressurized fluid which flows in an antegrade direction through said lumen of the drive shaft and is at least partially re-directed into the distal fluid inflatable support element.

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;   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 defining a central lumen and a longitudinal axis, the drive shaft configured for rotation about the longitudinal axis, wherein a first portion of the drive shaft is configured to be at least partially disposed within the sheath lumen while a distal portion of the drive shaft extends distally of the sheath lumen when the system is used for performing the rotational atherectomy, wherein a torque-transmitting coil of the drive shaft is disposed along an outermost exterior of the first portion of the drive shaft while a fluid impermeable membrane is disposed along an outermost exterior of the distal portion of the drive shaft; 
 an abrasive element that is mounted to the drive shaft and extends around less than half of a circumference of the drive shaft such that a center of mass of the abrasive element is offset from the longitudinal axis of the drive shaft, wherein the abrasive element comprises an abrasive outer surface that is fixedly positioned relative to the drive shaft; and 
 a distal stability element that is fixed to the distal portion of the drive shaft and that has a center of mass aligned with the longitudinal axis of the drive shaft, wherein the fluid impermeable membrane is exposed along an exterior of the distal stability element such that the exterior of the distal stability element is smoother and different from the abrasive outer surface of the abrasive element, and wherein the distal stability element being distally spaced apart from the abrasive element by the distal separation distance; and 
   a guidewire removable from the drive shaft of the rotational atherectomy device after the drive shaft is advanced over the guidewire across the stenotic lesion material in the blood vessel.   
     
     
         3 . The system of  claim 2 , wherein the abrasive element and the distal stability element are both fixed to the drive shaft so that the abrasive element and the distal stability element rotate together with the distal portion of the drive shaft. 
     
     
         4 . The system of  claim 2 , wherein the center of mass of the abrasive element is offset from the longitudinal axis of the drive shaft such that, during rotation of the drive shaft, the abrasive element has an orbital path about an axis of rotation that is substantially greater diameter than a travel path of the distal stability element. 
     
     
         5 . The system of  claim 2 , wherein a distalmost end of the drive shaft defines a distal facing port. 
     
     
         6 . The system of  claim 5 , wherein the rotational atherectomy device further comprises a movable element arranged in the drive shaft to adjust the distal facing port of the drive shaft from the opened condition to the closed condition. 
     
     
         7 . The system of  claim 2 , wherein the fluid impermeable membrane provides a fluid-impermeable lumen along the drive shaft. 
     
     
         8 . The system of  claim 2 , wherein the guidewire is configured to be slidably withdrawn from the central lumen of the drive shaft. 
     
     
         9 . The system of  claim 2 , wherein the distal stability element comprises an inflatable stability element. 
     
     
         10 . The system of  claim 2 , wherein the rotational atherectomy device further comprises a proximal stability element that is fixed to the drive shaft. 
     
     
         11 . The system of  claim 10 , wherein the proximal stability element has a center of mass aligned with the longitudinal axis of the drive shaft. 
     
     
         12 . The system of  claim 11 , wherein the proximal stability element comprises an inflatable stability element. 
     
     
         13 . The system of  claim 10 , wherein the distal and proximal stability elements are equally spaced apart from the abrasive element. 
     
     
         14 . The system of  claim 2 , wherein the torque-transmitting coil of the drive shaft is an outer torque transmitting coil. 
     
     
         15 . The system of  claim 14 , wherein the drive shaft further comprises an inner torque transmitting coil, at least a portion of the inner torque transmitting coil being surrounded by the fluid impermeable membrane. 
     
     
         16 . The system of  claim 2 , wherein the distal stability element comprise a fluid output port in fluid communication with the central lumen of the drive shaft. 
     
     
         17 . The system of  claim 2 , wherein the abrasive element comprises a solid body that is mounted to an outer region of the drive shaft. 
     
     
         18 . The system of  claim 2 , wherein the fluid impermeable membrane is folded on itself at the distal portion of the drive shaft so as to form the distal stability element between inner and outer layers of a folded region of the fluid impermeable membrane.