Systems and methods for twisting an expansion element of a cryoablation system

Patent metadata

Field	Value
Publication number	US-11026740-B2
Application number	US-201916730541-A
Country	US
Kind code	B2
Filing date	Dec 30, 2019
Priority date	Sep 1, 2009
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

A cryoablation catheter assembly includes a catheter that defines at least one coolant outtake region and receives a rotatable guide tube and a coolant transfer tube. The coolant transfer tube receives and transfers coolant from a coolant source to a distal end of the coolant transfer tube. An expansion element is coupled to a distal portion of the catheter and defines an inner expansion-element space. The inner expansion-element space is in fluid communication with the at least one coolant outtake region and the distal end of the coolant transfer tube. A distal end of the expansion element couples to the guide tube. A rotation system is coupleable to, or coupled to, a proximal end of the guide tube and rotates the distal end of the expansion element relative to the proximal end of the expansion element by rotating the guide tube relative to the catheter.

First claim

What is claimed is:

1. A catheter assembly comprising:
a catheter having a distal portion, a proximal portion, and a longitudinal length, the catheter configured and arranged for insertion into patient vasculature, the catheter comprising a body;
a rotatable guide tube disposed within the catheter, the guide tube having a proximal end and a distal end;
an expansion element defining an interior space and having a proximal end coupled to the body of the catheter and a distal end coupled to the rotatable guide tube, the expansion element having an inner layer and an outer layer;
a rotation system coupleable to, or coupled to, the proximal end of the guide tube, the rotation system including a linearly moveable actuator and a linear gear assembly mated with a rotational gear assembly, wherein the rotation system is configured and arranged to rotate the distal end of the expansion element relative to the proximal end of the expansion element by rotating the guide tube relative to the catheter, wherein the rotation system is configured and arranged such that linear movement of the actuator causes rotation of the guide tube.

2. The catheter assembly of claim 1 , wherein the expansion element includes an intra expansion-element space between the inner layer and outer layer, wherein the interior space of the expansion element and the intra expansion-element space are both in fluid communication with a fluid-drawing source.

3. The catheter assembly of claim 2 , wherein the fluid-drawing source is a vacuum.

4. The catheter assembly of claim 1 , wherein the rotation system is integrated into a control module comprising at least one sensor configured to monitor at least one condition within the catheter.

5. The catheter assembly of claim 4 , wherein the at least one condition is pressure.

6. The catheter assembly of claim 4 , wherein the at least one condition is temperature.

7. The catheter assembly of claim 1 , wherein the actuator is fixedly coupled to the linear gear assembly.

8. The catheter assembly of claim 7 , wherein the linear gear assembly further comprises a rack gear with a longitudinal length and a tactile control for controlling linear movement of the rack gear along the rotational gear assembly.

9. The catheter assembly of claim 8 , wherein the rotational gear assembly further comprises a spur gear that mates with the rack gear to convert linear movement of the rack gear to rotational movement of the spur gear.

10. The catheter assembly of claim 1 , further comprising a coolant transfer tube disposed in the catheter, the coolant transfer tube extending along at least a portion of the catheter such that a distal end of the coolant transfer tube extends beyond the distal portion of the catheter, wherein the coolant transfer tube defines a lumen configured and arranged to receive and transfer coolant from a coolant source to the distal end through the coolant transfer tube.

11. A method for cryoablating patient tissue, the method comprising:
inserting a catheter in patient vasculature, the catheter having a distal portion, a proximal portion, and a longitudinal length, the catheter comprising a body and defining at least one coolant outtake region, the catheter receiving a guide tube and a coolant transfer tube each extending along at least a portion of the catheter, wherein the guide tube extends beyond the distal portion of the catheter, the catheter having an expansion element coupled thereto, wherein a proximal end of the expansion element is coupled to the body and a distal end of the expansion element is coupled to the guide tube;
guiding the catheter in proximity to patient tissue to be ablated;
drawing coolant from a coolant source such that coolant flows along the coolant transfer tube and is sprayed into an interior of the expansion element, thereby expanding the expansion element and reducing the temperature of the expansion element to a temperature sufficiently low enough to ablate patient tissue upon contact;
contacting patient tissue with the expanded expansion element for a time period adequate to ablate tissue contacting the expansion element;
deflating the expansion element by drawing the coolant along the at least one coolant outtake region from the expansion element; and
while deflating the expansion element, also twisting the expansion element by rotating the guide tube relative to the catheter using a coupled rotation system, the rotation system including a linearly moveable actuator coupled to the guide tube and a linear gear assembly mated with a rotational gear assembly, wherein rotating the guide tube includes linearly moving the actuator relative to the catheter body, thereby twisting the expansion element.

12. The method of claim 11 , wherein expanding the expansion element includes controlling the rate of flow of coolant using a fluid-drawing source.

13. The method of claim 12 , wherein the fluid-drawing source is a vacuum or pump.

14. The method of claim 12 , wherein the expansion element includes an inner layer and an outer layer and an intra expansion-element space defined therebetween, wherein the interior of the expansion element and the intra expansion-element space are both in fluid communication with the fluid-drawing source, wherein deflating the expansion element includes drawing coolant out of the expansion element with the fluid-drawing source.

15. The method of claim 11 , wherein rotating the guide tube comprises translating the linear movement of the actuator to rotational movement of the guide tube.

16. The method of claim 15 , wherein the actuator is coupled to a linear gear assembly, the guide tube is coupled to a rotational gear assembly, and the linear and rotational gear assemblies are coupled to one another, wherein linearly moving the actuator moves the linear gear assembly which rotates the rotational gear assembly, thereby rotating the guide tube.

17. The method of claim 16 , wherein deflating the expansion element includes linearly moving the actuator a desired distance, wherein the distance corresponds to a predetermined number of rotations of the guide tube.

18. The method of claim 16 , wherein the linear gear assembly further comprises a rack gear with a longitudinal length, wherein the actuator controls linear movement of the rack gear along the rotational gear assembly.

19. The method of claim 18 , wherein the rotational gear assembly further comprises a spur gear that mates with the rack gear to convert linear movement of the rack gear to rotational movement of the spur gear.

20. The method of claim 11 , wherein guiding the catheter in proximity to patient tissue to be ablated comprises disposing the catheter into a steerable sheath.

Assignees

• Boston Scient Scimed Inc

Inventors

• Chun Byron

Classifications

• A61B2018/0212

  using an instrument inserted into a body lumen, e.g. catheter · CPC title

• A61B18/02 Primary

  by cooling, e.g. cryogenic techniques · CPC title

• A61B2018/0022

  Balloons · CPC title

• A61B2018/00214

  Expandable means emitting energy, e.g. by elements carried thereon · CPC title

• A61B2018/00202

  rotating · CPC title