Integrated electrical signal switching and amplifying system

• US 5,743,859 A
• Filed: 05/13/1996
• Issued: 04/28/1998
• Est. Priority Date: 11/13/1992
• Status: Expired due to Term

• Current Assignee: GE Marquette Medical Systems, Inc. (General Electric Company)
• Original Assignee: Quinton Electrophysiology Corporation
• Inventors: Fine, Richard Michael, Wodlinger, Harold Max
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): SCHAETZLE, KENNEDY
• Application Number:
  US08/648,529
• Time in Patent Office: 715 Days
• Field of Search: 128/709, 128/710, 128/696, 607/9, 607/18, 607/23, 600/522, 600/523, 600/509, 600/374
• US Class Current: 600/522
• CPC Class Codes: A61B 2562/226 comprising means for identifying the connector, e.g. to prevent incorrect connection to socket
• CPC Class Codes: A61B 5/30 Input circuits therefor
• CPC Class Codes: A61B 5/304 Switching circuits
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick
• CPC Class Codes: G16H 40/40 for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades

Abstract

A signal management system is disclosed which integrates a patient switching box and an amplification unit into a single compact enclosure sufficiently small to reside by the patient table in an operating unit set up for electrophysiology procedures. The system includes a front panel designed to accept standard ECG leads, a plurality of intracardiac leads, including leads available for stimulation and/or lesion generation, and a plurality of pressure channels. The front panel also includes a touch screen display to allow quick assignments of labels to each of the ECG or intracardiac leads and the pressure channels. The system includes an onboard microprocessor which allows any operation performed on the System to be automatically updated on a remote computer processing unit if attached, and vice-versa. Digital signal processors are used in the system to perform switching operations on the electrical signals received, and to perform gain, limiting and/or filtering processes thereon. The digital signal processors are automatically calibrated to adjust for varying gain and phase performance of the inputting front-end amplifiers which deliver the electrical signals from the intracardiac leads.

Claims

1. An integrated electrical signal switching and amplifying system for receiving intracardiac electrical signals from a patient, amplifying the intracardiac electrical signals from the patient, switching the amplified intracardiac electrical signals, and outputting the switched intracardiac electrical signals, said system comprising:

at least one electrical signal receiver for receiving intracardiac electrical signals from a patient,

at least one electrical signal amplifier for amplifying the intracardiac electrical signals received from the at least one electrical signal receiver,

at least one analog to digital converter for converting the amplified intracardiac electrical signals received from the amplifier into digital signals,

at least one digital signal processor for performing at least one signal switching operation on the amplified digital intracardiac electrical signals received from the converter,

at least one electrical signal output for outputting the switched intracardiac electrical signals received from said processor, and

means for visual review of the switched intracardiac electrical signals from the at least one electrical signal output.

2. A system according to claim 1 wherein said at least one electrical signal receiver includes means for receiving analog intracardiac electrical signals, and said at least one electrical signal amplifier includes means for converting the analog intracardiac electrical signals to digital intracardiac electrical signals associated therewith and said at least one digital signal processor further includes means for removing common mode signal noise from the digital intracardiac electrical signals.

3. A system according to claim 1 further including a microprocessor, said at least one digital signal processor being operatively interconnected with and controlled by said microprocessor at a location adjacent to the patient.

4. A system according to claim 1 further including a microprocessor which is operatively interconnected with and controls said digital signal processor from a location adjacent to the patient;

a separate processing unit at a location remote from the patient which is operatively interconnected with and controls said digital signal processor; and

an interactive display interconnected with said microprocessor and which allows operator control of said microprocessor therefrom.

5. A system according to claim 1 wherein said at least one digital signal processor further includes means for performing signal filtering operations on the amplified digital intracardiac electrical signals switched by said at least one digital signal processor.

6. A system according to claim 1 wherein said at least one electrical signal receiver includes a plurality of input terminals for receiving intracardiac electrical signals from one or more catheters interconnected therewith and said at least one electrical signal output further includes means for outputting information related to the position of the one or more catheters in the body of the patient and said plurality of input terminals receiving the intracardiac electrical signals from the one or more catheters therethrough.

7. A system according to claim 6 wherein said system further includes a microprocessor having means for receiving and storing information related to the position of said one or more catheters in the body of the patient and the intracardiac electrical signals via said plurality of input terminals.

8. A system according to claim 7 wherein said microprocessor includes means for storing a plurality of setup formats for identifying the positions of the one or more catheters interconnected to said plurality of input terminals and for receiving intracardiac electrical signals from the one or more catheters.

9. A system according to claim 7 further including a display means for displaying labels assigned to said plurality of input terminals.

10. A system according to claim 1 wherein said at least one electrical signal receiver further includes a plurality of electrical signal receivers for receiving intracardiac electrical signals from intracardiac catheters, a plurality of electrical signal receivers for receiving ECG electrical signals from ECG leads, and at least one electrical signal receiver for receiving pressure electrical signals from at least one pressure sensor.

11. A system according to claim 1 wherein said at least one digital signal processor is a differential amplifier and performs said at least one signal switching operation on the amplified digital intracardiac electrical signals.

12. A system according to claim 1 further including means for calibrating and wherein said at least one electrical signal amplifier includes a plurality of front-end amplifiers therein and said means for calibrating operates to correct for gain and phase performance variations between said plurality of front-end amplifiers of said at least one electrical signal amplifier.

13. A system according to claim 12 wherein said means for calibrating further includes means for determining and storing digital calibration values associated therewith and wherein said digital calibration values correspond to the difference between the gain and phase values of a known calibration signal and the gain and phase values of the known calibration signal as received by said at least one digital signal processor after the known calibration signal has passed through said plurality of front-end amplifiers.

14. A system according to claim 13 further including means for applying said digital calibration values to the amplified digital intracardiac electrical signals received by said at least one digital signal processor from said front-end amplifiers wherein the amplified digital intracardiac electrical signals received by said at least one digital signal processor are altered using the digital calibration values to correct for gain and phase performance variations between each of said plurality of front-end amplifiers.

15. An integrated intracardiac signal switching and amplifying system for receiving intracardiac signals from the body of a patient, amplifying the received intracardiac signals, switching the amplified intracardiac signals, and outputting the switched intracardiac signals, said system comprising:

an intracardiac signal receiver for receiving the intracardiac signals from a patient,

an intracardiac signal amplifier for amplifying the received intracardiac signals,

an analog to digital converter for converting the amplified intracardiac signals into digital intracardiac signals,

a digital signal processor for performing a signal switching operation on the digital intracardiac signals, and

an intracardiac signal output for outputting the switched intracardiac signals.

16. A system according to claim 15 wherein said signal receiver receives analog intracardiac signals from the body of a patient, and said signal amplifier converts the analog intracardiac signals to digital intracardiac signals and said digital signal processor further performs a common mode signal noise operation on the digital intracardiac signals.

17. A system according to claim 15 wherein said signal receiver includes a plurality of input terminals and said signal output further includes means for outputting information related to the origination of the intracardiac signals received via said input terminals.

18. A system according to claim 17 further including a microprocessor having means for receiving and storing information related to said input terminals and for receiving intracardiac signals.

19. A system according to claim 18 wherein said microprocessor includes means for storing a plurality of setup formats identifying the positions of catheters connected to said input terminals.

20. A system according to claim 15 wherein said signal receiver includes a plurality of intracardiac signal receivers for receiving electrical signals from intracardiac catheters, a plurality of ECG signal receivers for receiving electrical signals from ECG leads, and at least one pressure signal receiver for receiving electrical signals from at least one pressure sensor via said input terminals.

21. A system according to claim 20 wherein said signal receiver includes a plurality of input terminals and said signal output further includes means for outputting information related to the origination of said intracardiac and pressure signals via said input terminals.

22. A system according to claim 20 further including input terminals for receiving electrical signals from stimulation and lesion generating cardiac catheters.

23. A system according to claim 15 wherein said signal amplifier further includes a means for calibrating and said

means for calibrating operates to correct for gain and phase performance variations between said amplifier and the phase and gain of a known signal.

24. A system according to claim 23 wherein said means for calibrating includes storage means for storing digital calibration values in said said storage means and wherein said digital calibration values represent the difference between the gain and phase values of a known calibration signal and the gain and phase values of said known calibration signal as received by said digital signal processor after said known calibration signal has passed through said amplifier and is received by said digital signal processor.

25. A system according to claim 23 including means for automatically applying said stored digital calibration values to signals received by said digital signal processor from said amplifier such that said signals received by said digital signal processor are digitally calibrated to correct for gain and phase performance variations caused by said amplifier.

26. A method for processing an intracardiac signal from a patient with an integrated signal and amplifying system for use in an electrophysiology procedure, the method including:

receiving an intracardiac signal from the patient with a received,

amplifying the intracardiac signal received by the receiver with an amplifier to create an amplified signal,

converting the amplified signal received from the amplifier with an analog to digital converter to create a digital intracardiac signal,

performing a switching operation on the digital intracardiac signal received from the converter with a digital signal processor to create a switched digital intracardiac signal, and

outputting the switched intracardiac signal from the system.

27. The method of claim 26 further including the step of performing a common mode noise rejection operation on the digital intracardiac signal by the digital signal processor.

28. The method of claim 26 further including the step of processing the digital intracardiac signal for gain and signal limiting and filtering the digital intracardiac signal by the digital signal processor.

29. The method of claim 26 further including the step of performing a calibration of the system to correct variations between each of a plurality of front-end amplifiers used in the amplification of the received intracardiac signal by applying digital stored calibration values to the amplified intracardiac signals received by the digital signal processor.

30. The method of claim 29 further including the step of performing a calibration of the system to correct variations between each of said plurality of front-end amplifiers used in the amplification of the received intracardiac signal by applying stored calibration values to each of the amplified intracardiac signals received by the digital signal processor.