Magnetically guided catheters

• US 9,023,033 B2
• Filed: 08/04/2010
• Issued: 05/05/2015
• Est. Priority Date: 08/04/2010
• Status: Active Grant

• Current Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Original Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Inventors: Tegg, Troy T., Kauphusman, James V.
• Primary Examiner(s): ROANE, AARON F
• Application Number:
  US12/850,485
• Publication Number:
  US 20120035605A1
• Time in Patent Office: 1,735 Days
• Field of Search: 606/41
• US Class Current: 606/41
• 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 2018/00011 with fluids
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 34/73 Manipulators for magnetic surgery
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61M 2025/0166 Sensors, electrodes or the like for guiding the catheter to a target zone, e.g. image guided or magnetically guided
• CPC Class Codes: A61M 25/0127 Magnetic means; Magnetic markers
• CPC Class Codes: A61M 25/0158 with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A magnetically-guided catheter includes a tip positioning magnet in the distal electrode assembly configured to interact with externally applied magnetic fields for magnetically-guided movement. A magnetically-guided mapping catheter includes an electrically-conductive capsule in the form of a casing that includes a distal ablation surface and isolates the positioning magnet from bio-fluids to prevent corrosion. An open irrigation ablation catheter includes an isolated manifold that isolates the positioning magnet from contact with irrigation fluid to prevent corrosion.

Claims

1. An electrode assembly for an ablation catheter, comprising:

a positioning magnet body having a proximal shank portion and a distal portion;

a manifold including a distribution cavity configured to receive irrigation fluid and an irrigation passageway coupled to said cavity having a distal exit port for delivery of said fluid, said cavity and said passageway being isolated from said body; and

a unitary outer capsule surrounding said body so as to isolate said body from external bio-fluids, said capsule comprising electrically conductive material including a distal ablation surface.

2. The assembly of claim 1 wherein said body comprises one of a permanent magnet, a permanent magnet comprising rare earth elements and an electro-magnet.

3. The assembly of claim 2 wherein said permanent magnet comprises neodymium iron boron (NdFeB) material.

4. The assembly of claim 1 wherein said manifold includes a tubular portion having said distribution cavity and extending along an axis, said tubular portion including a proximal end portion configured to receive said fluid, said irrigation passageway extending from a distal end portion of said tubular portion, said passageway being in fluid communication with said tubular portion, said manifold being disposed in corresponding recesses in said body.

5. The assembly of claim 4 wherein said corresponding recesses in said body include a centrally-disposed, longitudinally-extending bore configured to receive said tubular portion of said manifold.

6. The assembly of claim 4 wherein said exit port associated with said passageway comprises one of a distal exit port, a side exit port and an angled exit port.

7. The assembly of claim 4 wherein said irrigation passageway is a radially-extending irrigation passageway.

8. The assembly of claim 4 wherein said capsule comprises an electrically conductive coating.

9. The assembly of claim 8 wherein said coating comprises one of:

(i) a first layer of Ni—

Ni material on an outer surface of said body, a second layer comprising gold (Au) material on said first layer and a third layer comprising platinum (Pt) material on said second layer; and

(ii) a first layer of Ni—

Ni material on an outer surface of said body, a second layer comprising titanium (Ti) material on said first layer and a third layer comprising platinum (Pt) material on said second layer.

10. The assembly of claim 1 wherein said body and said manifold extend along an axis wherein said irrigation passageway is an axially-extending irrigation passageway.

11. The assembly of claim 1 wherein said capsule includes (i) a cup-shaped tip cap configured to cover said distal portion of said body, and (ii) a cylindrical-shaped shank cover configured to surround said shank portion, said tip cap including at least one aperture corresponding to said irrigation exit port.

15. The assembly of claim 1 further including a safety line having distal end portion coupled to an inner bore of said body and a proximal end.

16. The assembly of claim 15 wherein said safety line comprises one of liquid crystal polymer (LCP) material and a para-aramid synthetic fiber.

12. An electrode assembly for an electrode catheter, comprising:

a positioning magnet body having a proximal shank portion and a distal portion; and

a unitary outer casing surrounding said body so as to isolate said body from external bio-fluids, said casing including a cup-shaped tip cap configured to cover said distal portion of said body and a cylindrical-shaped shank cover configured to surround said shank portion of said body, said casing including said cup-shaped tip cap comprising electrically conductive material, said shank cover being configured to receive a distal end portion of a catheter shaft.

13. The assembly of claim 12 wherein said body is one of a permanent magnet, a permanent magnet comprising rare earth elements and an electro-magnet.

14. The assembly of claim 13 wherein said permanent magnet comprises neodymium iron boron (NdFeB) material.