System and method for providing dynamic gain over non-noise electrocardiographic data with the aid of a digital computer
In one embodiment, a system and method for providing dynamic gain over non-noise electrocardiographic data with the aid of a digital computer are provided. A time series of a plurality of voltage values that comprises a digital representation of a raw electrocardiography (“ECG”) signal recorded by an ambulatory monitor recorder is obtained. One or more segments of the ECG signal is marked as noise, each of the segments including a plurality of the values, based on a difference between a maximum one and a minimum one of the values within that segment. Further segments not marked as noise are analyzed, each of the segments comprising a plurality of the values. A gain factor for all of the values in the analyzed further segments is determined based on the analysis.
1. A system for providing dynamic gain over non-noise electrocardiographic data with the aid of a digital computer, comprising:
a download station configured to execute code comprising:
a value module configured to obtain a time series of a plurality of voltage values that comprises a digital representation of a raw electrocardiography (“ECG”) signal recorded by an ambulatory monitor recorder;
a mark module configured to mark one or more segments of the ECG signal as noise, each of the segments comprising a plurality of the values, based on a difference between a maximum one and a minimum one of the values within that segment; and
an analysis module configured to analyze further segments not marked as noise each of the segments comprising a plurality of the values, and to determine a gain factor for all of the values in the analyzed further segments based on the analysis.
2. A system according to claim 1 , wherein the analysis comprises determining a maximum and a minimum values in each of the non-noise segments and determining a statistical correlation based on the maximum and the minimum values of each of the further segments.
3. A system in accordance with claim 1 , further comprising:
a filter module configured to apply a filter during the marking of the noise selected from the group comprising a high pass filter, a low pass filter, an amplitude change filter, and a zero-crossings filter.
4. A system according to claim 1 , wherein each of the further segments falls within temporal windows of a same duration.
5. A system according to claim 4 , wherein the duration is long enough to capture at least one heart beat.
6. A system according to claim 1 , the download station further comprising:
a bridging module configured to bridge the further segments to create a continuous ECG signal for display.
7. A system according to claim 6 , the download station further comprising:
a storage module configured to store the time series; and
a display module configured to display a representation of the raw ECG signal upon receiving a user command.
8. A method for providing dynamic gain over non-noise electrocardiographic data with the aid of a digital computer, comprising the steps of:
obtaining a time series of a plurality of voltage values that comprises a digital representation of a raw electrocardiography (“ECG”) signal recorded by an ambulatory monitor recorder;
marking one or more segments of the ECG signal as noise, each of the segments comprising a plurality of the values, based on a difference between a maximum one and a minimum one of the values within that segment; and
analyzing further segments not marked as noise each of the segments comprising a plurality of the values; and
determining a gain factor for all of the values in the analyzed further segments based on the analysis,
wherein the steps are performed by a suitably-programmed computer.
9. A method according to claim 8 , wherein the analysis comprises determining a maximum and a minimum values in each of the non-noise segments and determining a statistical correlation based on the maximum and the minimum values of each of the further segments.
10. A method in accordance with claim 8 , further comprising the step of:
applying a filter during the marking of the noise selected from the group comprising a high pass filter, a low pass filter, an amplitude change filter, and a zero-crossings filter.
11. A method according to claim 8 , wherein each of the further segments falls within temporal windows of a same duration.
12. A method according to claim 11 , wherein the duration is long enough to capture at least one heart beat.
13. A method according to claim 8 , further comprising:
bridging the further segments to create a continuous ECG signal for display.
14. A method according to claim 13 , the further comprising:
storing the time series; and
displaying a representation of the raw ECG signal upon receiving a user command.
15. An ambulatory adjustable encoding monitor recorder, comprising:
a memory configured to store a plurality of codes and a plurality of electrocardiographic values associated with each of the codes;
a microcontroller configured to sense electrocardiographic values during a sequence of temporal windows and to process the electrocardiographic values within each of the windows, the microcontroller further configured to:
calculate a mathematical relationship between a maximum one and a minimum one of the electrocardiographic values in each of the temporal windows;
compare each of the relationships to an at least one threshold;
based on the comparison of the relationship for at least one of the windows, adjust the plurality of the electrocardiographic values associated with each of the codes;
encode each of the electrocardiography values within that window with one of the codes based on the adjusted plurality of the electrocardiographic values associated with that code; and
write each of the codes into a sequence in the memory of the monitor recorder.
16. A monitor recorder according to claim 15 , wherein the adjusted plurality of the electrocardiographic windows are used for the processing of at least one of the windows following that window.
17. A monitor recorder according to claim 15 , the microcontroller further configured to:
define a desired value for the mathematical correlation; and
calculate a difference between the desired value and the at least one threshold; and
adjust the plurality of the electrocardiographic values based on the difference.
18. A monitor recorder according to claim 15 , the microcontroller further configured to:
define a length of each of the temporal windows and an acceptable peak-to-peak threshold associated with that window, wherein the at least one threshold comprises the peak-to-peak threshold.
19. A monitor recorder according to claim 18 , wherein the peak-to-peak threshold comprises 1.0 mv.
20. A monitor recorder according to claim 15 , the microcontroller further configured to:
associate a message regarding at least one of the adjustments with the codes stored in the memory.