Cooling tissue inside the body

• US 20060025840A1
• Filed: 08/02/2004
• Published: 02/02/2006
• Est. Priority Date: 08/02/2004
• Status: Abandoned Application

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Willard, Martin
• Application Number:
  US10/909,695
• Publication Number:
  US 20060025840A1
• Time in Patent Office: Days
• US Class Current: 607/113
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2018/0212 using an instrument inserted into a body lumen, e.g. catheter
• CPC Class Codes: A61B 2018/0262 using a circulating cryogenic fluid
• CPC Class Codes: A61F 2007/0056 for cooling
• CPC Class Codes: A61F 2007/126 for invasive application, e.g. for introducing into blood vessels
• CPC Class Codes: A61F 7/123 using a flexible balloon containing the thermal element
• CPC Class Codes: A61M 25/104 used for angioplasty

Abstract

Devices and methods for cooling a target tissue region inside the body are disclosed. A catheter for cooling blood includes an elongated member with a lumen extending longitudinally through a portion of the member. The lumen has an entry port and an exit port through which blood from a body vessel may enter and exit the lumen. An inflatable balloon is positioned between the entry and exit ports of the lumen, which when inflated, occludes the body vessel and prevent normal blood flow. A cooling element cools blood as it flows through the lumen. The cooling element may include a chamber that cools the blood by using a Joule-Thompson orifice to create a phase change of liquid to a gas. The cooling element may also include a thermoelectric cooler.

Claims

1. A catheter comprising:

an elongated member that has a lumen extending longitudinally through a portion of the member, the lumen having an entry port through which blood from a body vessel enters the lumen and an exit port through which the blood exits the lumen;

an inflatable balloon positioned between the entry and exit ports of the lumen; and

a cooling element that cools blood as it flows through the lumen.

2. The catheter of claim 1 wherein the entry and exit ports of the lumen are positioned such that when the catheter is in the body vessel, the entry and exit ports are both within the body vessel.

3. The catheter of claim 2 wherein the body vessel is a coronary artery.

4. The catheter of claim 1 wherein the inflatable balloon, when inflated, has an outer diameter that is approximately five millimeters or less.

5. The catheter of claim 1 wherein the lumen is structured to provide a blood flow of twenty milliliters per minute through the lumen with normal blood pressure.

6. The catheter of claim 5 wherein the lumen has a diameter of less than about 45 thousandths of an inch.

7. The catheter of claim 1 wherein the cooling element is located in a distal portion of the catheter.

8. The catheter of claim 1 wherein the cooling element further comprises a chamber that cools the blood by using a Joule-Thompson orifice to create a phase change of liquid to a gas.

9. The catheter of claim 8 wherein the inflatable balloon comprises an inflation chamber, and wherein the balloon'"'"'s inflation chamber serves as the chamber that cools the blood using the Joule-Thompson orifice.

10. The catheter of claim 1 wherein the cooling element comprises a thermoelectric cooler.

11. The catheter of claim 10 wherein the thermoelectric cooler comprises a plurality of thermoelectric semiconductors.

12. A method of providing cooled blood to a target tissue region inside a body, the method comprising:

introducing a catheter into a body vessel, the catheter having an inflatable balloon near the catheter'"'"'s distal end;

inflating the balloon to restrict normal blood flow to the target tissue region through the body vessel;

allowing blood to flow through a lumen in the balloon catheter from an entry port proximal to the balloon to an exit port distal to the balloon; and

cooling the blood as it flows through the lumen.

13. The method of claim 12 wherein the catheter is positioned in the body vessel such that the entry and exit ports of the lumen are also within the body vessel.

14. The method of claim 13 wherein the body vessel is a coronary artery.

15. The method of claim 12 wherein the method is performed during a percutaneous transluminal coronary angioplasty.

16. A catheter for providing cooled blood to a target tissue region inside a body, the catheter comprising:

an elongated member that has a lumen extending longitudinally through a portion of the member, the lumen having an entry port through which blood from a body vessel enters the lumen and an exit port through which blood exits the lumen; and

a chamber positioned in a distal portion of the catheter between the entry and exit ports of the lumen so that the chamber may cool the blood as it flows through the lumen by using a Joule-Thompson orifice to create a phase change of liquid to a gas.

17. The catheter of claim 16 wherein the entry and exit ports of the lumen are positioned such that when the catheter is in the body vessel, the entry and exit ports are both within the body vessel.

18. The catheter of claim 17 wherein the body vessel is a coronary artery.

19. The catheter of claim 16 wherein the chamber expands to occlude a body vessel to prevent normal blood flow to the target tissue region.

20. The catheter of claim 19 wherein the inflated outer diameter of the chamber is approximately five millimeters or less.