Event marker alignment by inclusion of event marker transmission latency in the real-time data stream

• US 6,535,763 B1
• Filed: 08/22/1999
• Issued: 03/18/2003
• Est. Priority Date: 08/22/1999
• Status: Expired due to Term

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Simms, Howard D. Jr., Hiebert, James F. W., Koshiol, Allan T.
• Primary Examiner(s): Getzow, Scott M.
• Application Number:
  US09/382,154
• Time in Patent Office: 1,304 Days
• Field of Search: 607/32, 607/5, 600/510
• US Class Current: 607/32
• CPC Class Codes: A61N 1/37247 User interfaces, e.g. input or presentation means
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data

Abstract

A cardiac rhythm management system transmits event markers from an implantable device to a remote user interface such as an external programmer. The event markers include timestamp information. A printed/displayed event marker representation is aligned to a printed/displayed heart signal representation based at least in part on the timestamp information. Proper alignment of the printed/displayed heart signal representation to the printed/displayed event marker and proper alignment of the printed/displayed event markers with respect to each other, provides more accurate diagnostic information to the caregiver. This assists the caregiver in using the cardiac rhythm management system to provide a patient with proper cardiac rhythm management therapy.

Claims

1. A cardiac rhythm management system, including:

an implantable cardiac rhythm management (CRM) device; and

a user interface (UI), remote from the CRM device, the user interface adapted to be communicatively coupled to the CRM device for receiving a substantially real-time event marker and a substantially real-time electrogram therefrom, in which the event marker includes a timestamp relating at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker, and based at least in part on the timestamp, the UI aligns an indication of the event marker to a substantially real-time representation of a heart signal on one of a display or a recording.

2. The system of claim 1, in which the heart signal is based on at least one of an electrogram signal communicated from the CRM device and a surface ECG signal.

3. The system of claim 1, in which the UI also aligns the indication of the event marker to the representation of the electrogram signal based on a fixed delay.

4. The system of claim 3, in which the event marker is one of a plurality of types of event markers, in which at least one type of event marker has a different transmission time from at least one other type of event marker.

5. The system of claim 4, in which the fixed delay is based on the longest transmission time among all of the types of event markers.

6. The system of claim 1 in which the UI is adapted to receive data from the CRM device in frames, in which each data frame includes a plurality of data slots including:

a first data slot associated with a first event marker associated with a first electrode; and

a second data slot associated with a second event marker associated with a second electrode different from the first electrode.

7. The system of claim 6, in which at least one event marker requires more than one data frame for transmission of the event marker from the CRM device to the UI.

8. The system of claim 7, in which a first type of event marker includes an express event marker including at least two bytes of data, and a second type of event marker includes a full event marker including more bytes of data than the express event marker.

9. The system of claim 8, in which the express event marker includes a Hamming code error correction field.

10. The system of claim 1, in which the timestamp relates at least in part to an approximate time between the an event associated with the event marker and another event associated with another event marker.

11. The system of claim 1 in which the timestamp relates at least in part to an approximate time between an event associated with the event marker and another event associated with a previous event marker associated with the same electrode.

12. The system of claim 1, in which the timestamp relates at least in part to an approximate time between an event associated with the event marker and another event associated with a previous event marker associated with the same heart chamber.

13. The system of claim 1, in which the timestamp relates at least in part to all approximate time between an event associated with the event marker and the transmission completion time associated with a previous event marker associated with the same heart chamber.

14. A cardiac rhythm management system, including:

an atrial lead, including at least one atrial electrode;

a ventricular lead, including at least one ventricular electrode;

an implantable cardiac rhythm management (CRM) device; and

an external programmer, including a screen display and a strip chart recorder, the programmer adapted to be communicatively coupled to the CRM device for receiving frames of data therefrom, each data frame including;

at least one first channel electrogram data slot;

at least one second channel electrogram data slot;

an atrial event marker data slot, for transmitting a first atrial event marker having a first transmission time and a second atrial event marker having a second transmission time different from the first transmission time, the second atrial event marker including a flag field, an event code field, a timestamp field, and a Hamming-coded error correction field;

a ventricular event marker data slot, for transmitting a first ventricular event marker having a third transmission time and a second ventricular event marker having a fourth transmission time different from the third transmission time, the second atrial event marker including a flag field, an event code field, a timestamp field, and a Hamming-coded error correction field; and

in which the programmer aligns, on one of the display or the recorder, indications of the atrial and ventricular event markers to at least one of (a) an electrogram representation or (b) a surface electrocardiogram (ECG) representation, and in which the alignment of event markers is based on the associated timestamps and a fixed delay corresponding to the longest transmission time of the event markers, and in which at least one event marker requires more than one data frame for transmission of the event marker from the CRM device to the external programmer, and in which the timestamp field in the atrial and ventricular event markers relates to an approximate time between the event marker and a previous event marker associated with the same heart chamber.

15. The system of claim 14, further including at least one shock electrode, and in which the first and second electrogram data slots provide electrogram signal data associated with two electrodes selected from the group consisting of:

the atrial electrode, the ventricular electrode, and the shock electrode.

16. A method, including:

observing the occurrence of an event associated with an implantable cardiac rhythm management device;

timestamping the event with a time that relates to the event'"'"'s time of occurrence;

transmitting a substantially real-time electrogram and an event marker, which includes the timestamp, to a remote user interface, wherein the timestamp relates at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker;

receiving the electrogram and the event marker at the remote user interface;

aligning in time, based at least in part on the timestamp, a representation of the event marker to a substantially real-time representation of a cardiac signal; and

displaying, recording, or storing the aligned event marker representation and cardiac signal representation.

17. The method of claim 16, in which the timestamping the event is carried out relative to an occurrence of an earlier event.

18. The method of claim 16, in which the timestamping the event is carried out relative to a transmission completing time of a previous event marker being transmitted at the event'"'"'s time of occurrence.

19. The method of claim 16, in which the aligning in time is also based on a fixed delay.

20. The method of claim 19, in which the aligning in time is also based on a fixed delay associated with a transmission time of an event marker.

21. The method of claim 20, in which the transmission and receiving the event marker includes transmitting and receiving a plurality of types of event markers, at least one type of event marker having a transmission time that is different from one other type of event marker.

22. The method of claim 21, in which the aligning in time is also based on a fixed delay associated with a longest transmission time of the different types of event markers.

23. The method of claim 16, it which the transmitting the event marker is carried out over a plurality of data frames.

24. The method of claim 16, in which transmitting the event marker includes coding at least a portion of the event marker with a Hamming code error checking field included in the event marker.

25. A method, including:

receiving first and second channel electrogram data associated with first and second electrodes associated with all implantable cardiac rhythm management device;

observing the occurrence of a first event associated with the first electrode;

transmitting a first event marker from the device based on the occurrence of the first event;

observing, during the transmitting of the first event marker, the occurrence of a second event associated with the first electrode;

timestamping a second event marker with information relating to the time between the first and second events;

receiving the first event marker at a remote user interface (UI);

transmitting the second event marker, which includes the timestamp, to a remote UI after completion of the transmission of the first event marker;

receiving the second event marker at the remote UI;

aligning in time, based at least in part on the timestamp, a representation of the second event marker to a representation of a cardiac signal; and

displaying, recording, or storing the aligned second event marker representation and the cardiac signal representation.

26. A cardiac rhythm management system, including:

an implantable cardiac rhythm management (CRM) device; and

a user interface (UI), remote from the CRM device, the user interface adapted to be communicatively coupled to the CRM device for receiving a substantially real-time event marker therefrom, in which the event marker includes a timestamp relating at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker, and based at least in part on the timestamp, the UI aligns an indication of the event marker to a substantially real-time representation of a heart signal on one of a display or a recording, and in which the UI also aligns the indication of the event marker to the representation of the electrogram signal based on a fixed delay.

27. The system of claim 26, in which the event marker is one of a plurality of types of event markers, in which at least one type of event marker has a different transmission time from at least one other type of event marker.

28. The system of claim 27, in which the fixed delay is based on the longest transmission time among all of the types of event markers.

29. A cardiac rhythm management system, including:

an implantable cardiac rhythm management (CRM) device; and

a user interface (UI), remote from the CRM device, the user interface adapted to be communicatively coupled to the CRM device for receiving a substantially real-time event marker therefrom, in which the event marker includes a timestamp relating at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker, and based at least in part on the timestamp, the UI aligns an indication of the event marker to a substantially real-time representation of a heart signal on one of a display or a recording, and in which the UI is adapted to receive data from the CRM device in frames, in which each data frame includes a plurality of data slots including;

a first data slot associated with a first event marker associated with a first electrode; and

a second data slot associated with a second event marker associated with a second electrode different from the first electrode.

30. The system of claim 29, in which at least one event marker requires more than one data frame for transmission of the event marker from the CRM device to the UI.

31. The system of claim 30, in which a first type of event marker includes an express event marker including at least two bytes of data, and a second type of event marker includes a full event marker including more bytes of data than the express event marker.

32. The system of claim 31, in which the express event marker includes a Hamming code error correction field.

33. A cardiac rhythm management system, including:

an implantable cardiac rhythm management (CRM) device; and

a user interface (UI), remote from the CRM device, the user interface adapted to be communicatively coupled to the CRM device for receiving a substantially real-time event marker therefrom, in which the event marker includes a timestamp relating at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker, and based at least in part on the timestamp, the UI aligns an indication of the event marker to a substantially real-time representation of a heart signal on one of a display or a recording, and in which the timestamp relates at least in part to an approximate time between an event associated with the event marker and the transmission completion time associated with a previous event marker associated with the same heart chamber.

34. A method, including:

observing the occurrence of an event associated with an implantable cardiac rhythm management device;

timestamping the event with a time that relates to the event'"'"'s time of occurrence, in which the timestamping the event is carried out relative to a transmission completion time of a previous event marker being transmitted at the event'"'"'s time of occurrence;

transmitting an event marker, which includes the timestamp, to a remote user interface, wherein the timestamp relates at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker;

receiving the event marker at the remote user interface;

aligning in time, based at least in part on the timestamp, a representation of the event marker to a substantially real-time representation of a cardiac signal; and

displaying, recording, or storing the aligned event marker representation and cardiac signal representation.

35. The method of claim 34, in which the aligning in time is also based on a fixed delay.

36. The method of claim 35, in which the aligning in time is also based on a fixed delay associated with a transmission time of an event marker.

37. The method of claim 36, in which the transmitting and receiving the event marker includes transmitting and receiving a plurality of types of event markers, at least one type of event marker having a transmission time that is different from one other type of event marker.

38. The method of claim 37, in which the aligning in time is also based on a fixed delay associated with a longest transmission time of the different types of event markers.

39. A method, including:

observing the occurrence of an event associated with an implantable cardiac rhythm management device;

timestamping the event with a time that relates to the event'"'"'s time of occurrence, in which the transmitting the event marker is carried out over a plurality of data frames;

transmitting an event marker, which includes the timestamp, to a remote user interface, wherein the timestamp relates at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker;

receiving the event marker at the remote user interface;

aligning in time, based at least in part on the timestamp, a representation of the event marker to a substantially real-time representation of a cardiac signal; and

displaying, recording, or storing the aligned event marker representation and cardiac signal representation.

40. A method, including:

observing the occurrence of an event associated with an implantable cardiac rhythm management device;

timestamping the event with a time that relates to the event'"'"'s time of occurrence;

transmitting an event marker, which includes the timestamp, to a remote user interface, wherein the timestamp relates at least in part to an approximate time between an event associated with the event marker and another event associated with another event marker, in which transmitting the event marker includes coding at least a portion of the event marker with a Hamming code error checking field included in the event marker;

receiving the event marker at the remote user interface;

aligning in time, based at least in part on the timestamp, a representation of the event marker to a substantially real-time representation of a cardiac signal; and

displaying, recording, or storing the aligned event marker representation and cardiac signal representation.