Material removal device having improved material capture efficiency and methods of use
An improved atherectomy catheter includes a part for propelling fluid distally in a tissue collection chamber. The part includes a drive shaft having a proximal end and a distal portion, and a propeller attached to the distal portion of the drive shaft.
1. An atherectomy catheter, comprising:
a body having an opening;
a rotatable shaft coupled to the body;
a cutting element coupled to the rotatable shaft, the cutting element having a cutting edge;
a tissue collection chamber coupled to the body and positioned distal to the cutting element; and
a part for propelling fluid distally in the tissue collection chamber, the part including a drive shaft having a proximal end and a distal portion, and a propeller attached to the distal portion of the drive shaft, wherein the proximal end of the drive shaft is attached to the cutting element.
2. The catheter of claim 1 , wherein the cutting element has a cup-shaped surface, the cup-shaped surface being configured to re-direct tissue cut by the cutting edge in a distal direction when the cup-shaped surface moves in the distal direction.
3. The catheter of claim 1 , wherein the propeller is located distally of the opening and proximally of a distal end of the collection chamber.
4. The catheter of claim 1 , wherein the propeller is located immediately distally of the opening.
5. The catheter of claim 1 , wherein the propeller is located in a distal half of the collection chamber.
6. The catheter of claim 1 , wherein the proximal end of the drive shaft is attached to a cup-shaped surface of the cutting element, the cup-shaped surface being configured to re-direct tissue cut by the cutting edge in a distal direction when the cup-shaped surface moves in the distal direction.
7. The catheter of claim 1 , wherein the tissue collection chamber comprises vent holes.
8. The catheter of claim 7 , wherein the tissue collection chamber comprises 10 to 200 vent holes.
9. The catheter of claim 7 , wherein the vent holes have a diameter of from 25 to 200 microns.
10. The catheter of claim 1 , wherein the collection chamber comprises a portion at a distal end that can be opened to remove cut material and particles.
11. The catheter of claim 1 , wherein the cutting element is movable between a stored position and a cutting position relative to the opening.
12. A method of removing material from a body lumen, the method comprising:
providing an atherectomy catheter, the atherectomy catheter comprising:
a body having an opening;
a rotatable shaft coupled to the body;
a cutting element coupled to the rotatable shaft, the cutting element having a cutting edge;
a tissue collection chamber coupled to the body and positioned distal to the cutting element; and
a part for propelling fluid distally in the tissue collection chamber, the part including a drive shaft having a proximal end and a distal portion, and a propeller attached to the distal portion of the drive shaft, wherein the proximal end of the drive shaft is attached to the cutting element;
placing the catheter in the body lumen; and
moving the catheter in the body lumen to contact the cutting element with the material in the body lumen.
13. The method of claim 12 , wherein the catheter is moved in a distal direction to contact the cutting edge with the material in the body lumen.
14. The method of claim 12 , wherein the catheter is placed in the body lumen with the cutting element in the stored position and the catheter is moved to contact the material with the cutting element in a cutting position.
15. The method of claim 12 , wherein the body lumen is a blood vessel.