Tissue excision, cutting, and removal systems and methods
The disclosure provides various embodiments of catheters that can be used for various procedures. Embodiments of methods are also provided that can be performed with catheters in accordance with the present disclosure.
1. A catheter having a proximal end, a distal end, and defining a longitudinal axis, the catheter comprising:
a first elongate member having a proximal end, a distal end and defining a lumen at least partially along a length of the first elongate member, the first elongate member having a collapsible basket mounted thereon having an open distally facing end;
a tether operably coupled to and at least partially surrounding a perimeter of the open distally facing end of the collapsible basket, the tether further extending proximally parallel to the longitudinal axis toward the proximal end of the catheter, wherein the open distally facing end of the collapsible basket is configured to be collapsed by applying tension to the tether along a proximal direction;
a second elongate member slidably disposed within the lumen of the first elongate member, the second elongate member having a proximal end and a distal end, wherein the distal end of the second elongate member can be advanced distally beyond the distal end of the first elongate member;
a cutting snare loop operably coupled to the distal end of the second elongate member, wherein:
the cutting snare loop is configured to be laterally collapsed and withdrawn proximally into a distal end of the lumen of the first elongate member by withdrawing the second elongate member along the proximal direction into the lumen of the first elongate member;
the cutting snare loop is configured to be deployed distally out of the distal end of the lumen of the first elongate member by advancing the second elongate member distally;
the cutting snare loop is configured to self-orient into a first plane that is oriented transversely with respect to the longitudinal axis of the catheter when deployed distally outwardly from the lumen of the first elongate member, and further wherein a user can use the basket to at least partially surround an object attached to a tissue mass, collapse the basket around the object by applying tension to the actuator, and then sever the tissue mass by cutting through the tissue mass with the deployable cutting snare loop.
2. The catheter of claim 1 , wherein cutting by way of the cutting snare loop is accomplished at least in part by withdrawing the cutting snare loop proximally into the lumen of the first elongate member.
3. The catheter of claim 1 , wherein the collapsible basket is formed from a laser cut hypotube formed into a stent-like pattern defined by zig-zag rows of struts.
4. The catheter of claim 1 , wherein a proximal end of the collapsible basket is fastened to the elongate member by a radiopaque marker band and the first elongate member further includes a second radiopaque marker at a distal end of the first elongate member.
5. The catheter of claim 1 , further comprising a tissue grasper, wherein the tissue grasper can be advanced distally out of the collapsible basket to grasp tissue.
6. The catheter of claim 5 , wherein the the tissue grasper includes a plurality of radially outwardly biased gripping arms, wherein the radially outwardly biased gripping arms collapse radially inwardly when the tissue grasper is advanced along a proximal direction with respect to the collapsible basket.
7. The catheter of claim 6 , wherein each said gripping arm is formed from a planar strip of material that terminates in a radially inwardly converging distal tip and includes proximal end affixed to a distal end of an inner elongate member, and a preformed bend that bends the arm radially outwardly, and then bends radially inwardly as the arm approaches a tapered distal tip.
8. The catheter of claim 1 , wherein the cutting snare loop is coupled to an electrical power source to electrify the cutting snare loop.
9. The catheter of claim 1 , wherein the perimeter of the open distally facing end of the collapsible basket is disposed in a second plane that is oriented transversely with respect to the longitudinal axis of the catheter.
10. The catheter of claim 9 , wherein the cutting snare loop is configured to align axially with the open distally facing end of the collapsible basket when the cutting snare loop is deployed to permit an object to be removed from a patient's anatomy to be received through the cutting snare loop and through the open distally facing end of the collapsible basket at the same time.
11. A method of removing a mitral clip coupled to two native mitral valve leaflets while a patient's heart is beating, comprising:
providing a catheter according to claim 1 ;
deploying the cutting snare loop;
sliding the cutting snare loop around the mitral clip;
advancing the cutting snare loop along the mitral clip to a location where the mitral clip it adjoins native valve tissue;
at least partially surrounding the mitral clip with the collapsible basket;
collapsing the collapsible basket around the mitral clip to grip the mitral clip by applying tension to the tether;
severing the mitral clip from the native valve tissue by cutting the native valve tissue with the deployable cutting snare loop; and
removing the mitral clip from the patient.
12. The method of claim 11 , wherein the procedure is performed percutaneously.
13. The method of claim 11 , wherein the procedure is performed apically.
14. A method of using the catheter to remove a mitral clip, comprising:
providing a catheter according to claim 5 ;
advancing a distal end of the catheter to a mitral clip attached to a pair of native mitral valve leaflets;
distally extending the tissue grasper to surround the mitral clip; and
grasping the mitral clip with the tissue grasper to hold the mitral clip in place.