Electrophysiology laboratory system for use with magnetic resonance imaging systems

Patent metadata

Field	Value
Publication number	US-12350055-B2
Application number	US-202016798243-A
Country	US
Kind code	B2
Filing date	Feb 21, 2020
Priority date	Apr 23, 2012
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

An electrophysiological laboratory system comprises a subsystem configured to perform diagnostic and/or therapeutic functions, a medical device, and an interface module disposed therebetween. The medical device comprises a shaft having proximal and distal portions, high- and low-impedance electrical pathways disposed within the shaft, and an electrode disposed at the distal portion of the shaft and electrically coupled to one or both of the high- and low-impedance electrical pathways. The electrode is configured to perform diagnostic and/or therapy delivery functions. The interface module comprises a high-impedance channel configured to couple the high-impedance pathway of the medical device to the subsystem, and to attenuate magnetic resonance RF and gradient field pulses generated by the MRI system. The interface module further comprises a low-impedance channel configured to couple the low-impedance pathway of the medical device to the subsystem.

First claim

What is claimed is:

1. An interface module for an electrophysiology laboratory (EP lab) system configured for use with a magnetic resonance imaging (MRI) system, the EP lab system including a medical device and at least one subsystem, the at least one subsystem including a diagnostic subsystem or a therapeutic subsystem, the interface module comprising:
a housing;
a first port on an exterior of the housing, the first port configured to mate with a first connector of the medical device that is electrically coupled to a high-impedance pathway of the medical device;
a second port on the exterior of the housing, the second port configured to mate with a second connector of the medical device that is electrically coupled to a low-impedance pathway of the medical device;
a third port on the exterior of the housing, the third port configured to mate with a first connector of the at least one subsystem;
a fourth port on the exterior of the housing, the fourth port configured to mate with a second connector of the at least one subsystem;
a high-impedance channel located within the housing, the high-impedance channel comprising first wired circuitry extending between the first port and the third port within the housing, the first wired circuitry configured to attenuate magnetic resonance radio frequency pulses and gradient field pulses generated by the MRI system while still communicating first electrical signals between the medical device and the at least one subsystem; and
a low-impedance channel located within the housing and including a plurality of electrical pathways, each of the plurality of electrical pathways comprising second wired circuitry extending between the second port and the fourth port within the housing, the second wired circuitry configured to communicate second electrical signals between the medical device and the at least one subsystem.

2. The interface module of claim 1 , wherein the first wired circuitry comprises a high input impedance amplifier.

3. The interface module of claim 1 , wherein the low-impedance channel is a first low-impedance channel, and the interface module further includes a second low-impedance channel configured to electrically couple a patch electrode with the at least one subsystem.

4. The interface module of claim 1 , wherein the first wired circuitry comprises a low-pass filter configured to be electrically coupled to the high-impedance electrical pathway of the medical device and to attenuate the magnetic resonance radio frequency pulses generated by the MRI system.

5. The interface module of claim 4 , wherein the first wired circuitry further comprises a voltage limiter circuit electrically coupled to an output of the low-pass filter and configured to attenuate the magnetic resonance gradient field pulses generated by the MRI system.

6. The interface module of claim 5 , wherein the first wired circuitry further comprises a high input impedance amplifier configured to be electrically coupled between an output of the voltage limiter circuit and the at least one subsystem to which the high-impedance electrical pathway of the medical device is coupled.

7. The interface module of claim 1 , wherein:
one electrical pathway of the plurality of electrical pathways of the low-impedance channel is configured to provide an uninterruptable connection between the low-impedance electrical pathway of the medical device and the at least one subsystem to which the low-impedance electrical pathway of the medical device is coupled; and
another electrical pathway of the plurality of electrical pathways comprises an interrupter circuit, the interrupter circuit configured to be electrically coupled between the low-impedance electrical pathway of the medical device and the at least one subsystem to which the low-impedance electrical pathway of the medical device is coupled.

8. A system comprising:
the interface module of claim 1 ; and
the medical device comprising the first connector of the medical device, the second connector of the medical device, the high-impedance pathway of the medical device that is electrically coupled to the first connector of the medical device, and the low-impedance pathway of the medical device that is electrically coupled to the second connector of the medical device.

9. The system of claim 8 , wherein the high-impedance electrical pathway has an impedance of greater than or equal to 2kΩ.

10. The system of claim 8 , wherein the high-impedance electrical pathway includes a non-ferromagnetic electrical conductor having a high impedance.

11. The system of claim 10 , wherein the electrical conductor is constructed of a metal alloy selected from the group consisting of:
a nickel-chromium alloy,
a nickel-iron alloy,
a copper-nickel alloy, and
a manganese-nickel-copper alloy.

12. The system of claim 8 , wherein the high-impedance electrical pathway includes an electrical conductor with a plurality of segments and a resistor element electrically connected in series between a pair of conductor segments.

13. The system of claim 8 , wherein the low-impedance electrical pathway includes an inductive element configured to:
attenuate magnetic resonance radio frequency pulses, and
limit a magnitude of radio frequency currents induced in the low-impedance electrical pathway.

14. The system of claim 13 , wherein the inductive element is a choke.

15. The system of claim 13 , wherein the low-impedance electrical pathway further includes a non-ferromagnetic electrical conductor having a plurality of segments, and the inductive element is electrically connected in series between a pair of conductor segments.

16. The system of claim 8 , further comprising a temperature sensor electrically coupled to the low-impedance electrical pathway.

17. The interface module of claim 1 , wherein the first ends of each of the plurality of electrical pathways are electrically coupled to one another.

18. The system of claim 8 , wherein the high-impedance electrical pathway is configured to limit a magnitude of radio frequency currents induced in the high-impedance pathway by magnetic resonance radio frequency pulses.

19. The interface module of claim 7 , wherein the interrupter circuit comprises a sample-and-hold circuit.

20. The interface module of claim 19 , wherein the sample-and-hold circuit comprises a capacitor configured to disconnect the subsystem.

Assignees

• St Jude Medical Atrial Fibrillation Div Inc

Inventors

• Deno D Curtis
• Schweitzer Jeffrey A

Classifications

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• A61B5/28 Primary

  for electrocardiography [ECG] · CPC title

• G01R33/285

  Invasive instruments, e.g. catheters or biopsy needles, specially adapted for tracking, guiding or visualization by NMR · CPC title

• A61N1/05

  for implantation or insertion into the body, e.g. heart electrode (A61N1/06 takes precedence) · CPC title

• A61B2018/00577

  Ablation · CPC title