IMPLANTABLE MEDICAL DEVICE DIAGNOSTIC DATA ACQUISITION AND STORAGE

• US 20100234914A1
• Filed: 06/01/2010
• Published: 09/16/2010
• Est. Priority Date: 09/05/2006
• Status: Active Grant

• Current Assignee: Allan T. Koshiol, Joseph E. Bange, Zhe Shen
• Original Assignee: Allan T. Koshiol, Joseph E. Bange, Zhe Shen
• Inventors: SHEN, Zhe, KOSHIOL, Allan T., BANGE, Joseph E.
• Granted Patent: US 8,200,324 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/335 using integrated circuit memory devices
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/7232 involving compression of the physiological signal, e.g. to extend the signal recording period
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: A61N 1/3706 Pacemaker parameters stimulation threshold A61N1/371

Abstract

A method carried out by a therapeutic implantable medical device includes detecting a plurality of physiologic episodes and recording a set of diagnostic data associated with the plurality of physiological episodes. The plurality of physiologic episodes are prioritized based on episode types associated with the physiologic episodes. The diagnostic data is analyzed based on a minimum and maximum number associated with each episode type relating to a minimum and maximum number of sets of diagnostic data to be recorded for the associated episode type. The recorded set of diagnostic data is deleted only if a later recorded set of diagnostic data is associated with a detected physiologic episode having an episode type of a higher priority, and deletion of the set of diagnostic data would not result in fewer sets of diagnostic data than the minimum number specified for the episode type associated with the set of diagnostic data.

Claims

1. A method carried out by a therapeutic implantable medical device (IMD), the method comprising:

detecting a plurality of physiologic episodes;

recording a set of diagnostic data associated with the plurality of physiological episodes;

prioritizing the plurality of physiologic episodes based on episode types associated with the physiologic episodes;

analyzing the diagnostic data based on a minimum number and a maximum number associated with each episode type, wherein the minimum number indicates a minimum number of sets of diagnostic data to be recorded for the associated episode type, and wherein the maximum number indicates a maximum number of sets of diagnostic data to be recorded for the associated episode type; and

deleting the recorded set of diagnostic data only if a later recorded set of diagnostic data is associated with a detected physiologic episode having an episode type of a higher priority, and deletion of the set of diagnostic data would not result in fewer sets of diagnostic data than the minimum number specified for the episode type associated with the set of diagnostic data.

2. The method as recited in claim 1, further comprising:

associating a therapy delivery attempt with one of the plurality of physiologic episodes, wherein the therapy delivery attempt occurs at a time after the associated physiologic episode;

recording another set of diagnostic data at the time of the therapy delivery attempt; and

associating the another set of diagnostic data with the associated physiologic episode.

3. The method as recited in claim 1, wherein the recorded set of diagnostic data comprises one of electrogram data, marker data, processed waveform data, or other physiologic sensor data.

4. The method as recited in claim 3, further comprising compressing the single set of diagnostic data using differential pulse code modulation (DPCM) and Huffman encoding.

5. The method as recited in claim 1, wherein recording the set of diagnostic data comprises copying diagnostic data from a circular buffer into another part of memory.

6. The method as recited in claim 1, wherein the recording step comprises:

in response to detecting a first physiologic episode, recording diagnostic data that is received during a first time span ending at a first specified end time;

in response to detecting a second physiologic episode during the first time span, specifying a second end time; and

recording diagnostic data that is received during a second time span ending at the second specified end time to form the set of diagnostic data associated with both the first physiologic episode and the second physiologic episode.

7. The method as recited in claim 6, and further comprising:

delivering therapy during the first time span or the second time span;

in response to delivering therapy, specifying a third end time; and

recording diagnostic data that is received during a third time span ending at the third specified end time, wherein the diagnostic data received during the third time span is included in the set of diagnostic data.

8. The method as recited in claim 7, further comprising associating the delivering of therapy with one of the first physiologic episode or the second physiologic episode.

9. The method as recited in claim 8, further comprising transmitting data descriptive of the delivering of therapy in response to receiving a request for diagnostic data related to the physiologic episode that is associated with the delivering of therapy.

10. The method as recited in claim 6, further comprising associating the first physiologic episode with the set of diagnostic data by determining that the first physiologic episode occurred at a time included in the first time span.

11. The method as recited in claim 6, wherein the prioritizing step comprises prioritizing the first physiologic episode and the second physiologic episode based on a first episode type and a second episode type, respectively.

12. The method as recited in claim 11, and further comprising:

detecting a third physiologic episode of a third episode type having a higher priority than the first physiologic episode;

in response to detecting the third physiologic episode, recording diagnostic data to form another set of diagnostic data;

determining whether more than a specified minimum number of sets of diagnostic data associated with episodes of the first episode type exist in memory; and

deleting the set of diagnostic data associated with the first physiologic episode if more than the specified minimum number of sets of diagnostic data associated with episodes of the first episode type exist in memory.

13. The method as recited in claim 11, and further comprising:

detecting a third physiologic episode of a third episode type; and

recording diagnostic data to form another set of diagnostic data associated with the third physiologic episode if the maximum number of sets of diagnostic data associated with the third episode type do not exist in memory.

14. The method as recited in claim 6, wherein the IMD is operable to deliver therapy, and wherein the method further comprises:

generating a physiologic episode data structure associated with, and descriptive of, the first physiologic episode;

detecting one or more attempts to deliver therapy in response to detecting the first physiologic episode;

for each of the one or more attempts to deliver therapy, generating a therapy delivery attempt data structure associated with, and descriptive of, the therapy delivery attempt; and

associating all of the therapy delivery attempt data structures with the physiologic episode data structure.

15. The method as recited in claim 14, wherein associating all of the therapy delivery attempt data structures with the physiologic episode data structure comprises generating a linked list of the therapy delivery attempt data structures.

16. An implantable medical device (IMD) configured for implantation in a patient to monitor cardiac activity in, and deliver therapy to, the patient'"'"'s heart, the IMD comprising:

a pulse generator operable to deliver pacing pulses and shock pulses;

a plurality of leads having proximate ends coupled to the pulse generator and distal ends affixed to the patient'"'"'s heart at selected locations, wherein the leads are configured to pick up electrical activity in the patient'"'"'s heart, and wherein the leads are further configured to deliver the pacing pulses and the shock pulses to the patient'"'"'s heart;

a memory storing a prioritization schedule of cardiac episodes, wherein the prioritization schedule specifies a priority for each of a plurality of types of cardiac episodes, a minimum number indicating a minimum number of data sets to be recorded for each of the cardiac episodes, and a maximum number indicating a maximum number of data sets to be recorded for each of the cardiac episodes; and

a processor operable to delete a first recorded set of diagnostic data associated with a type of cardiac episode of a first priority, only if a second received set of diagnostic data is associated with a type of cardiac episode of a second priority that is higher than the first priority, and deletion of the first set of diagnostic data would not result in fewer sets of diagnostic data than the minimum number specified for the type of episode associated with the first set of diagnostic data.

17. The IMD as recited in claim 16, wherein the processor is further operable to delete the first set of diagnostic data only if fewer than the maximum number of sets of diagnostic data specified for the type of episode associated with the second set of diagnostic data have been recorded.

18. The IMD as recited in claim 16, further comprising a circular buffer receiving diagnostic data.