Apparatus for interpreting and displaying cardiac events of a heart connected to a cardiac pacing means

• US 4,791,936 A
• Filed: 06/20/1986
• Issued: 12/20/1988
• Est. Priority Date: 02/15/1985
• Status: Expired due to Term

• Current Assignee: Pacesetter AB
• Original Assignee: Siemens Pacesetter, Inc. (Abbott Laboratories Incorporated)
• Inventors: Snell, Jeffery D., Mann, Brian M., Sholder, Jason A.
• Primary Examiner(s): Jaworski, Francis J.
• Assistant Examiner(s): Manuel, George
• Application Number:
  US06/876,612
• Time in Patent Office: 914 Days
• Field of Search: 128/696, 128/419 PT, 128/903, 128/697, 128/702, 128/712, 340/870.01, 340/870.18, 340/870.26
• US Class Current: 600/510
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61N 1/37254 Pacemaker or defibrillator security, e.g. to prevent or inhibit programming alterations by hackers or unauthorised individuals

Abstract

An apparatus for interpreting and displaying cardiac events of a heart connected to an implanted cardiac pacing means (2) is disclosed. The apparatus includes a telemetry head (4), at least one interpreting means (6), and a controller (14). Information telemetered from the implanted pacing means is separated into identifiable sets of data pertaining to prescribed functions, such as atrial events, ventricular events, pacemaker timed events, sensor events, and the like. Skin ECG information may also be received through another interpreting means (12) in addition to pacemaker telemetered data. Parallel processing channels are employed to process all the received data while maintaining synchronization therebetween. Memory means (16) allow the synchronized processed data to be stored for subsequent print out through a D/A converter (20) and printer (22), or to be displayed on a display monitor (26). The display monitor is controlled by display logic (24) that includes the capability to simultaneously display a plurality of selected data sets while maintaining the synchronization therebetween, and that further allows displayed events to be identified with unique markers (44, 46, 64, 66 ) or synchronized with displayed time intervals (82, 84, 92, 94) associated with the operation of the pacemaker.

Claims

1. An apparatus for displaying cardiac events of a heart connected to an implanted cardiac pacemaker of a patient, said apparatus comprising:

first receiving means for receiving a first set of telemetered information from said implanted pacemaker;

second receiving means for receiving a second set of telemetered information from said implanted pacemaker;

controller means coupled to said first and second receiving means for synchronizing in time the telemetered information received through said first and second receiving means, and for processing the information thus received in parallel while maintaining the synchronization therebetween, said controller means generating digital command signals representative of the information received through the first and second receiving means and the synchronization therebetween;

memory means for storing said digital command signals; and

display means responsive to said digital command signals stored in said memory means for simultaneously displaying a synchronized representation of the telemetered information received through the first and second receiving means.

2. The apparatus of of claim 1 wherein said first receiving means comprises telemetry head means for receiving telemetered information from said implanted pacemaker coupled to said controller means via a first information channel;

and wherein said second receiving means comprises said telemetry head means coupled to said controller means via a second information channel.

3. The apparatus of claim 1 further including third receiving means for receiving a third set of information from skin electrodes placed at the skin of said patient, said third set of information being separate and distinct from the first and second sets of information received through said first and second receiving means.

4. An apparatus for displaying cardiac events of a heart connected to an implanted cardiac pacemaker of a patient, said apparatus comprising:

telemetry head means for receiving telemetered information from said implanted pacemaker;

controller means coupled to said telemetry head means via channel means for synchronizing in time the telemetered information received over the channel means, and for processing a plurality of sets of information contained within said telemetered information in parallel while maintaining the synchronization therebetween, said controller means generating command signals representative of the information contained in each of said sets of information and the synchronization therebetween;

said channel means including means for transferring to said controller means from said telemetry head means each of said plurality of sets of information in a way that maintains the identity of each set of information, each set of information including information relating to the pacemaker and events sensed by the pacemaker;

memory means for storing said command signals; and

display means responsive to said command signals stored in said memory means for simultaneously displaying a synchronized representation of the information derived from a selected plurality of said sets of information received through said telemetry head means and said channel means.

5. The apparatus of claim 4 wherein a first set of said plurality of sets of information contains cardiac event information sensed within said heart, and a second set of said plurality of sets of information contains pacemaker status information relating to the operation of said implanted cardiac pacemaker.

6. The apparatus of claim 5 wherein said first set of information contains cardiac event information sensed within the atrium of said heart, and wherein a third set of information contains cardiac event information sensed within the ventricle of said heart.

7. The apparatus of claim 4 further including means for receiving skin ECG information within said controller means as a separate set of information, said skin ECG information being processed in parallel with the received sets of telemetered information while maintaining the synchronization between the skin ECG information and the telemetered information.

8. In combination with an implanted cardiac pacemaker having telemetry means for telemetering data sensed and measured by said pacemaker, an apparatus for displaying a plurality of cardiac events in synchronization, said apparatus comprising

telemetry head means for receiving said telemetered data;

processing means for processing said received telemetered data, said processing means including

means for separating said telemetered data into a plurality of sets of data, each set of data relating to a specific cardiac/pacemaker event, at least one of said plurality of sets of data representing specific cardiac/pacemaker events that are sensed by said pacemaker, and another of said plurality of sets of data representing marker information that identifies the type of cardiac/pacemaker event that has been sensed and the time at which said event was sensed,

means for interpreting and processing said sets of data while maintaining the synchronization therebetween,

means for generating command signals representative of the synchronization between said sets of data, and

memory means for storing said processed sets of data and said command signals; and

display means coupled to said processing means for selectively displaying a synchronized representation of the information contained in a plurality of said sets of data,

said display means including means for displaying said sensed cardiac/pacemaker event in a way that the display is marked with said marker information so that the display apparatus identifies the type of cardiac/pacemaker event that occurred and the time at which it occurred.

9. The display apparatus of claim 8 wherein said marker information includes information relating to the beginning of a refractory period initiated by said pacemaker.

10. The display apparatus of claim 8 wherein said processing means further includes means for receiving a set of data relating to skin ECG data, said skin ECG data comprising data sensed at the skin of a patient that is not telemetered through said telemetry head means, and wherein the data separating means of said processing means separates said skin ECG data into an identifiable set of data while maintaining the synchronization between said skin ECG data and said plurality of sets of telemetered data.

11. An apparatus for displaying cardiac/pacemaker events of a heart in communication with a cardiac pacemaker, said pacemaker including means for sensing and monitoring a plurality of cardiac/pacemaker events and telemetering respective data signals representative of the occurrence of said cardiac/pacemaker events, said apparatus comprising:

means for receiving said data signals;

means for processing said data signals in parallel in a plurality of data channels, said means for processing including

means for classifying said data signals as belonging to one of a plurality of specified data sets,

means for directing the data signals of each data set to a respective data channel, and

means for maintaining the synchrony or timed relationship between the data signals of each data set within each data channel as said data signals are processed for display;

means for displaying a selected plurality of said data signals in a single multi-channel time-base display;

said means for displaying including;

a display surface,

means for displaying on said display surface a plurality of display channels having elapsed time as one axis thereof, and

means for displaying in each of said display channels a representation of selected data signals from a specified data set, each such representation depicting the occurrence of a corresponding cardiac/pacemaker event as a function of time, the combined display channels thereby depicting a selected plurality of cardiac/pacemaker events as a function of time, whereby a synchronized display of said selected plurality of cardiac/pacemaker events is realized.

12. The apparatus of claim 11 wherein a fourth of said data sets comprises data signals representing a sensed physiological parameter of a patient in whom said cardiac pacemaker is carried.

13. The apparatus of claim 11 wherein a first of said data sets comprises data signals representing sensed intracardiac ECG activity, and a second of said data sets comprises data signals identifying specific events, such as the sensing of a P-wave, included in the first data set.

14. The apparatus of claim 13 wherein a third data set comprises data signals representing specified time intervals associated with the operation of said pacemaker.

15. A method of displaying cardiac/pacemaker events of a heart controlled by an implanted cardiac pacemaker, said pacemaker including means for sensing and monitoring a plurality of cardiac/pacemaker events and telemetering respective data signals depicting the occurrence of said cardiac/pacemaker signals to an external, non-implanted receiving apparatus, said receiving apparatus including display means for displaying a plurality of data channels in a synchronized display, said method comprising the steps of:

(1) separating the received data signals into a plurality of data sets, each data set containing data signals relating to a specific cardiac/pacemaker function,

(2) processing the data sets in parallel processing channels, said processing in each channel including;

(a) generating command signals identifying the sequence and timed relationship of the information contained in said data sets, said sequence and timed relationship of a given data set including the time when a particular data signal was received, the duration of said particular data signal, and the length of time between specified data signals within the same data set, and

(b) storing said data sets and command signals for subsequent retrieval;

(3) selectively presenting a plurality of data sets with respective command signals to said display means; and

(4) displaying, in each data channel of said synchronized display, under control of said command signals, a selected one of said plurality of data sets, the events represented by said data sets being displayed in a sequence and timed relationship representative of the sequence and timed relationship of the information derived from the received data signals.

16. A method of externally identifying the types of signals sensed by an implanted medical device, said implanted medical device having transmitting means for sending to a non-implanted monitoring device the signals sensed internally by the implanted medical device, said method comprising the steps of:

(1) transmitting the sensed signals of the implanted medical device to the non-implanted monitoring device;

(2) transmitting, in conjunction with each transmitted signal sent in step (1), a marker code signal that identifies the sensed signal that has been transmitted;

(3) processing the signals transmitted in steps (1) and (2) within said non-implanted monitoring device in order to prepare such signals for display; and

(4) displaying the sensed signal and its associated marker code signal on a multi-channel display surface of the non-implanted monitoring device, said step of displaying including;

(a) presenting the sensed signal on a first display channel of said display surface, said first display channel having a desired parameter, such as amplitude, as one axis thereof, and having time as another axis thereof, whereby the sensed signal is displayed as a function of time, and

(b) presenting the marker code signal on a signal display channel of said display surface, said marker code signal being presented as an identifiable symbol that is displayed in synchrony with the sensed signal displayed on the first display channel, each component of interest of the displayed sensed signal being marked with an appropriate marker code that identifies that component of sensed signal.

17. The signal identification method of claim 16 wherein the implanted medical device comprises a pacemaker coupled to a heart and wherein the sensed signals comprise a first signal representing activity sensed in the atrium of the heart and a second signal representing activity sensed in the ventricle of the heart, and wherein step (4) (a) includes presenting the first signal on the first display channel of the display surface and presenting the second signal on a third display channel of the display surface, whereby both said first and second sensed signals are displayed as a function of time.