CATHETER APPARATUSES, SYSTEMS, AND METHODS FOR RENAL NEUROMODULATION

• US 20120136350A1
• Filed: 10/21/2011
• Published: 05/31/2012
• Est. Priority Date: 10/21/2010
• Status: Active Grant

• Current Assignee: Medtronic Ardian Luxembourg SARL (Medtronic Plc)
• Original Assignee: Medtronic Ardian Luxembourg SARL (Medtronic Plc)
• Inventors: Goshgarian, Justin, Clark, Benjamin J., Leung, Mark S., Aboytes, Maria G., Dhamodharasamy, Rajeshkumar
• Granted Patent: US 9,084,610 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/00323 Cables or rods
• CPC Class Codes: A61B 2017/00331 with preformed bends
• CPC Class Codes: A61B 2018/00047 using Peltier effect
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00434 Neural system
• CPC Class Codes: A61B 2018/00511 Kidney
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/1807 using light other than laser radiation
• CPC Class Codes: A61N 1/36057 adapted for stimulating afferent nerves

Abstract

Catheter apparatuses, systems, and methods for achieving renal neuromodulation by intravascular access are disclosed herein. One aspect of the present application, for example, is directed to apparatuses, systems, and methods that incorporate a catheter treatment device comprising an elongated shaft. The elongated shaft is sized and configured to deliver an energy delivery element to a renal artery via an intravascular path. Thermal or electrical renal neuromodulation may be achieved via direct and/or via indirect application of thermal and/or electrical energy to heat or cool, or otherwise electrically modulate, neural fibers that contribute to renal function, or of vascular structures that feed or perfuse the neural fibers.

Claims

1. A catheter apparatus, comprising:

an elongated shaft extending along an axis, the elongated shaft having a proximal portion and a distal portion, wherein the elongated shaft comprises—

a force transmitting section at the proximal portion of the elongated shaft;

a transition section distal to the force transmitting section and having a lesser stiffness than the force transmitting section, wherein the transition section has a proximal region and a distal region;

a first flexure zone comprising a deflectable tubular body extending from the distal region of the transition section, wherein the first flexure zone and the transition section comprise a circumferential cut pattern having a decreasing density of circumferential cuts toward the proximal region of the transition section; and

a second flexure zone extending distally from the first flexure zone; and

an energy delivery element coupled to the distal portion of the elongated shaft and configured to deliver energy to modulate a renal nerve at a treatment site within the renal artery.

2. The catheter apparatus of claim 1 wherein the circumferential cut pattern comprises a laser-cut pattern.

3. The catheter apparatus of claim 1 wherein the circumferential cut pattern comprises a variable pitch pattern in which the spacing between adjacent cuts is greater at the proximal region of the transition section than at the distal region of the transition section.

4. The catheter apparatus of claim 1 wherein the circumferential cut pattern comprises a plurality of discrete cuts.

5. The catheter apparatus of claim 1 wherein the circumferential cut pattern comprises a continuous helical cut.

6. The catheter apparatus of claim 1 wherein:

two individual cuts at the distal region of the transition section are spaced apart from each other by an axial distance of about 0.4 mm; and

two individual cuts at the proximal region of the transition section are spaced apart from each other by an axial distance of about 5.7 mm.

7. The catheter apparatus of claim 1 wherein the elongated shaft is configured to make a transitional bend from the aorta of a patient to the renal artery of the patient.

8. The catheter apparatus of claim 1 wherein the transition section has a length from about 14 cm to about 20 cm.

9. The catheter apparatus of claim 1 wherein the second flexure zone comprises a laser cut pattern including a spine with projecting ribs.

10. The catheter apparatus of claim 1 wherein a cumulative length of the transition section, the first flexure zone, and the second flexure zone is from about 10 cm to about 40 cm.

11. A catheter apparatus, comprising:

an elongated shaft extending along an axis, the elongated shaft having a proximal portion and a distal portion, wherein the elongated shaft comprises—

a force transmitting section at the proximal portion of the elongated shaft;

a transition section distal to the force transmitting section, the transition section having a first circumferential cut pattern and an axial length from about 4 cm to about 6 cm;

a first flexure zone distal to the transition section, the first flexure zone having a second circumferential cut pattern different from the first circumferential cut pattern; and

a second flexure zone extending distally from the first flexure zone; and

an energy delivery element coupled to the distal portion of the elongated shaft and configured to delivery energy to modulate a renal nerve at a treatment site within the renal artery.

12. The catheter apparatus of claim 11 wherein the first circumferential cut pattern has a decreasing density of circumferential cuts toward a proximal region of the transition section.

13. The catheter apparatus of claim 11 wherein a cumulative length of the transition section, the first flexure zone, and the second flexure zone is from about 10 cm to about 20 cm.

14. The catheter apparatus of claim 11 wherein the elongated shaft is configured to make transitional bends from a radial artery of a patient to the renal artery of the patient.

15. The catheter apparatus of claim 11 wherein at least a portion of the shaft comprises nitinol.

16. The catheter apparatus of claim 11 wherein the second flexure zone and the energy delivery element are sized and configured for intravascular delivery into the renal artery via a 6 French guide catheter.

17. The catheter apparatus of claim 11 wherein the first circumferential cut pattern comprises a variable pitch pattern and the second circumferential cut pattern comprises a constant pitch pattern.

18. The catheter apparatus of claim 11 wherein the second flexure zone comprises a laser cut pattern including a spine with connecting ribs.

19. A catheter apparatus for intravascular renal neuromodulation, comprising:

an elongated shaft extending along an axis, the elongated shaft comprising a proximal portion and a distal portion, the distal portion including a controlled flexure zone;

an energy delivery element coupled to the controlled flexure zone, the energy delivery element configured to contact an intravascular tissue surface and deliver energy to renal nerves positioned adjacent to the intravascular tissue surface; and

an active cooling element, wherein—

the controlled flexure zone is configured for controlled flexure about the axis to position the energy delivery element into contact with the intravascular tissue surface;

the energy delivery element is configured to apply energy via the intravascular tissue surface to ablate the renal nerves; and

the active cooling element is configured to remove heat from the energy delivery element.

20. The catheter apparatus of claim 19 wherein the active cooling element comprises an infusion port in the energy delivery element, and wherein the infusion port is in fluid communication with a thermal fluid infusion source.

21. The catheter apparatus of claim 20 wherein the thermal fluid comprises a cryogenic fluid.

22. The catheter apparatus of claim 19 wherein the energy delivery element and active cooling element together comprise an irrigated electrode.

23. The catheter apparatus of claim 22 wherein the irrigated electrode comprises six infusion ports in fluid communication with a thermal fluid infusion source.

24. The catheter apparatus of claim 22 wherein the irrigated electrode comprises a drilled interior portion configured to accept a fluid supply lumen.

25. The catheter apparatus of claim 22 wherein the irrigated electrode comprises a plurality of laser-cut apertures.

26. The catheter apparatus of claim 22 wherein the irrigated electrode comprises helical shape wound around a thermal fluid infusion source.

27. The catheter apparatus of claim 22 wherein the irrigated electrode comprises a plurality of braided filaments and interstitial spaces among the filaments.

28. The catheter apparatus of claim 19, further comprising a temperature sensor coupled to the energy delivery element.

29. The catheter apparatus of claim 28, further comprising a feedback control system configured to alter the removal of heat by the active cooling element in response to the monitored temperature.