Atherectomy devices and methods

1. A method of rotationally abrading a material along an interior of an arteriovenous graft, the system comprising:

simultaneously rotating an array of eccentric abrasive burrs within an interior of a synthetic arteriovenous graft at a rotational speed of 20,000 to 160,000 rpms so that at least one eccentric abrasive burr in the array travels in an orbital path having an orbit diameter multiple times greater than an outer maximum diameter of said at least one eccentric abrasive burr, the array of eccentric abrasive burrs being fixedly mounted to a torque-transmitting coil that defines a longitudinal axis extending in a longitudinal direction; and

during said simultaneously rotating the array of eccentric abrasive burrs within the interior of the synthetic arteriovenous graft, reciprocating the array of eccentric abrasive burrs back and forth in the longitudinal direction within the interior of the synthetic arteriovenous graft;

wherein during said simultaneously rotating the array of eccentric abrasive burrs within an interior of the synthetic arteriovenous graft, simultaneously rotating a distal concentric metallic element along with the array of eccentric abrasive burrs within an interior of the synthetic arteriovenous graft, the distal concentric metallic element having an abrasive outer coating and being fixedly mounted to the torque-transmitting coil at a position distally of the array of eccentric abrasive burrs so that the distal concentric metallic element has a center of mass aligned with the longitudinal axis.

2. The method of claim 1 , wherein the array of eccentric abrasive burrs are fixedly mounted to a distal end portion of the torque-transmitting coil such that a center of mass of each eccentric abrasive burr in the array is offset from the longitudinal axis.

3. The method of claim 2 , wherein the array of eccentric abrasive burrs comprises a helical array such that a center of mass of each eccentric abrasive burr in the helical array is offset from the longitudinal axis and the centers of mass of the eccentric abrasive burrs in the helical array are arranged along a path that spirals around the longitudinal axis.

4. The method of claim 3 , wherein in response to rotation of the torque-transmitting coil within the interior of the synthetic arteriovenous graft, the helical array of eccentric abrasive burrs rotates together with the distal concentric metallic element and at least one eccentric abrasive burr in the helical array orbits around the longitudinal axis in the orbital path while the distal concentric metallic element remains aligned with the longitudinal axis.

5. The method of claim 1 , wherein the abrasive outer coating of the concentric metallic element is configured to define an initial abrading path through a stenotic lesion material within the synthetic arteriovenous graft.

6. The method of claim 5 , wherein the concentric metallic element is positioned distally of the helical array of eccentric abrasive burrs such that the eccentric abrasive burrs are movable in the longitudinal direction through the stenotic lesion material after the initial abrading path is defined by the distal concentric metallic element.

7. The method of claim 1 , further comprising activating an electric motor housed within an actuator handle assembly positioned at a proximal end portion of the torque-transmitting coil to drive said simultaneously rotation of the array of eccentric abrasive burrs within the interior of the synthetic arteriovenous graft at the rotational speed of 20,000 to 160,000 rpms.

8. The method of claim 7 , further comprising slidably moving a carriage within a housing of the actuator handle assembly to reciprocate the array of eccentric abrasive burrs back and forth in the longitudinal direction, wherein the carriage is slidably movable in the longitudinal direction at the proximal end of the torque-transmitting coil.

9. The method of claim 8 , wherein said slidably moving a carriage within a housing of the actuator handle assembly comprises moving the electric motor together with the carriage within the housing of the actuator handle assembly.

10. The method of claim 9 , wherein the actuator handle assembly comprises an electrical switch to activate the electric motor to drive said rotation of the array of eccentric abrasive burrs within the interior of the synthetic arteriovenous graft at the rotational speed of 20,000 to 160,000 rpm.

11. The method of claim 10 , wherein the electric motor of the actuator handle assembly is configured to modify the rotational speed of the drive shaft so as to modify the orbit diameter of the orbital path of the at least one eccentric abrasive burr in the array.

12. The method of claim 1 , wherein the synthetic arteriovenous graft has an outer diameter multiple times greater than a largest diameter of all of the eccentric abrasive burrs in the array.

13. The method of claim 12 , wherein each of eccentric abrasive burrs in the array has an outer diameter of 1.5 mm to 2.5 mm.

14. The method of claim 13 , wherein the array of eccentric abrasive burrs comprises five spherical abrasive burrs spaced apart from one another along the torque-transmitting coil.

15. The method of claim 14 , wherein a central abrasive burr of the five spherical abrasive burrs has a diameter that is greater than or equal to a diameter of a proximal-most abrasive burr and a distal-most abrasive burr of the array of eccentric abrasive burrs.

16. The method of claim 14 , wherein the five spherical abrasive burrs of the helical array of eccentric abrasive burrs have the same diameter.

17. A method of rotationally abrading a material along an interior of an arteriovenous graft, the system comprising:

simultaneously rotating an array of eccentric abrasive burrs within an interior of a synthetic arteriovenous graft at a rotational speed of 20,000 to 160,000 rpms so that at least one eccentric abrasive burr in the array travels in an orbital path having an orbit diameter multiple times greater than an outer maximum diameter of said at least one eccentric abrasive burr, the array of eccentric abrasive burrs being fixedly mounted to a torque-transmitting coil that defines a longitudinal axis extending in a longitudinal direction; and

during said simultaneously rotating the array of eccentric abrasive burrs within the interior of the synthetic arteriovenous graft, reciprocating the array of eccentric abrasive burrs back and forth in the longitudinal direction within the interior of the synthetic arteriovenous graft;

activating an electric motor housed within an actuator handle assembly positioned at a proximal end portion of the torque-transmitting coil to drive said simultaneously rotation of the array of eccentric abrasive burrs within the interior of the synthetic arteriovenous graft at the rotational speed of 20,000 to 160,000 rpms; and

slidably moving a carriage within a housing of the actuator handle assembly to reciprocate the array of eccentric abrasive burrs back and forth in the longitudinal direction, wherein the carriage is slidably movable in the longitudinal direction at the proximal end of the torque-transmitting coil;

wherein said slidably moving a carriage within a housing of the actuator handle assembly comprises moving the electric motor together with the carriage within the housing of the actuator handle assembly.

18. A method of rotationally abrading a material along an interior of an arteriovenous graft, the system comprising:

simultaneously rotating an array of eccentric abrasive burrs within an interior of a synthetic arteriovenous graft at a rotational speed of 20,000 to 160,000 rpms so that at least one eccentric abrasive burr in the array travels in an orbital path having an orbit diameter multiple times greater than an outer maximum diameter of said at least one eccentric abrasive burr, the array of eccentric abrasive burrs being fixedly mounted to a torque-transmitting coil that defines a longitudinal axis extending in a longitudinal direction;

during said simultaneously rotating the array of eccentric abrasive burrs within the interior of the synthetic arteriovenous graft, reciprocating the array of eccentric abrasive burrs back and forth in the longitudinal direction within the interior of the synthetic arteriovenous graft wherein the synthetic arteriovenous graft has an outer diameter multiple times greater than a largest diameter of all of the eccentric abrasive burrs in the array;

wherein each of eccentric abrasive burrs in the array has an outer diameter of 1.5 mm to 2.5 mm;

wherein the array of eccentric abrasive burrs comprises five spherical abrasive burrs spaced apart from one another along the torque-transmitting coil.