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US5277189A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for the measurement and analysis of cardiac rates and amplitude variations

Assignee: NID Inc
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Filing: 1991-08-16
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Granted: 1994-01-11
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Expires: 2011-08-16
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Abstract

Abstract A method and apparatus are provided for measuring selected patient heartbeat parameters such as heartrates and amplitude variations, for processing the measured parameters to place them in more usable form and for analyzing measured and processed heartbeat parameters to obtain certain useful information concerning the condition of the patient's cardiac function. Measurement preferably involves detection and storage of at least two of the P, R and T pulses for each heartbeat and the conversion of such information into time series for selective heartrates. Indicators δ j are computed for selected ones of the time series for selected values of j and the computed δ j 's are then compared against stored δ j values to obtain a measure of the state of cardiac function. The time series are preferably notched, detrended and normalized prior to being analyzed.

Inventors

  • 👤 Laurence A. Jacobs

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 07:25
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/024; A61B5/0245

Claims Analysis

Total Claims: 45
Claim 1
Independent Claim 60 words
A method for measuring selected instantaneous patient heart pulse parameters comprising the steps of: taking heartbeat readings on the patient; detecting at least two of the P, R and T pulses for each heartbeat; determining the times at which each detected pulse occurs; and storing as a time series the times of each of the detected pulses for successive heartbeats.
Claim 2
Independent Claim 60 words
A method for measuring selected instantaneous patient heart pulse parameters comprising the steps of: taking heartbeat readings on the patient; detecting at least two of the P, R and T pulses for each heartbeat; determining the times at which each detected pulse occurs; and storing as a time series the times of each of the detected pulses for successive heartbeats.
Claim 3
Dependent Claim 41 words
A method as claimed in claim 1 wherein said readings are taken on a plurality of channels and wherein the storing step includes the steps of normally storing the pulse times for detected pulses from a selected one of said channels.
Claim 4
Dependent Claim 56 words
A method as claimed in claim 2 wherein the time series storing step includes the steps of comparing times for corresponding detected pulses from different channels; and taking predetermined action if the time for a detected pulse from the selected channel is not consistent with the times detected from the other channels for the corresponding pulse.
Claim 5
Dependent Claim 20 words
A method as claimed in claim 1 wherein amplitude is also stored for each pulse for which time is stored.
Claim 6
Dependent Claim 21 words
A method as claimed in claim 1 wherein times are stored for the P, R and T pulses of each heartbeat.
Claim 7
Dependent Claim 34 words
A method as claimed in claim 5 including the step of converting the stored pulse times into heartrates for at least one of P-P, R-R, T-T, P-R, R-T, T-P, T-R, R-P and P-T heartrates.
Claim 8
Dependent Claim 33 words
A method as claimed in claim 5 including the step of converting the stored pulse times into heartrates for at least one of P-P, T-T, P-R, R-T, T-P, T-R, R-P and P-T heartrates.
Claim 9
Dependent Claim 22 words
A method as claimed in claim 1 wherein said detecting step includes the step of utilizing matched filters in the detection process.
Claim 10
Dependent Claim 18 words
A method as claimed in claim 8 including the step of deriving the matched filters from the readings.
Claim 11
Dependent Claim 41 words
A method as claimed in claim 1 wherein said detecting step includes the steps of detecting the R pulse for the heartbeat, scanning back for the P pulse for the heartbeat, and scanning ahead for the T pulse for the heartbeat.
Claim 12
Independent Claim 34 words
A method for analyzing a measured heartbeat parameter comprising the steps of: converting the measured heartbeat parameter into a time series; deriving selected Indicator values for the time series; and corresponding stored Indicator values.
Claim 13
Independent Claim 34 words
A method for analyzing a measured heartbeat parameter comprising the steps of: converting the measured heartbeat parameter into a time series; deriving selected Indicator values for the time series; and corresponding stored Indicator values.
Claim 14
Dependent Claim 30 words
A method as claimed in claim 11 wherein the Indicator values are δ j values where j may have values from 1 to n, with n being at least 5.
Claim 15
Dependent Claim 27 words
A method as claimed in claim 11 wherein the measured heartbeat parameter is heartrate, the measured heartrate being converted into a time series of a selected heartrate.
Claim 16
Dependent Claim 29 words
A method as claimed in claim 11 wherein the measure heartbeat parameter is peak voltage for each heartbeat, the measured peak voltages being converted into a peak voltage time-series.
Claim 17
Dependent Claim 19 words
A method as claimed in claim 11 wherein the stored Indicator values are standard values contained in a database.
Claim 18
Dependent Claim 31 words
A method as claimed in claim 11 wherein the measured heartbeat parameters are from a given subject; and wherein the stored Indicator values are from previous measurements on the same subject.
Claim 19
Dependent Claim 48 words
A method as claimed in claim 11 wherein said deriving step includes the step of deriving a set of Differential Indicators δ j from the time series, and said comparing step includes the step of comparing the derived set of Differential Indicators against corresponding stored Differential Indicator values.
Claim 20
Dependent Claim 34 words
A method as claimed in claim 11 wherein said determining step includes the step of determining the cardiac function state of the heart from which the heartrate was measured from the derived Indicator values.
Claim 21
Dependent Claim 26 words
A method as claimed in claim 11 wherein the derived Indicator values quantify the complexity of the heartbeat parameters, such complexity being indicative of cardiac function.
Claim 22
Dependent Claim 25 words
A method as claimed in claim 11 including the step; performed before said deriving step, of notching the time series to eliminate unwanted detected peaks.
Claim 23
Dependent Claim 75 words
A method as claimed in claim 20 wherein said notching step includes the steps of determining the mean for the time series, determining the deviation from the mean for each entry of the time series; determining if the standard deviation from the mean for each entry exceeds a predetermined threshold, eliminating the value for each entry having a deviation from the mean exceeding the threshold, and substituting a selected average value for the eliminated value.
Claim 24
Dependent Claim 27 words
A method as claimed in claim 21 wherein the substituted selected average value is the mean of the preceding and succeeding entry values in the time series.
Claim 25
Dependent Claim 22 words
A method as claimed in claim 21 wherein the steps of said notching step are repeated recursively until predetermined conditions are satisfied.
Claim 26
Dependent Claim 28 words
A method as claimed in claim 11 including the step, performed before said deriving step, of detrending the time series to remove low-frequency variations in the time series.
Claim 27
Dependent Claim 40 words
A method as claimed in claim 24 wherein said detrending step includes the steps of low-pass filtering the time series to isolate frequencies below a predetermined minimum threshold, and subtracting the results of the filtering step from the time series.
Claim 28
Dependent Claim 16 words
A method as claimed in claim 24 including the step of normalizing the detrended time series.
Claim 29
Dependent Claim 64 words
Apparatus for measuring selected instantaneous patient heart pulse parameters comprising: means for taking heartbeat readings on the patient; means for detecting at least two of the P, R and T pulses for each heartbeat; means for determining the time at which each detected pulse occurs; and means for storing as a time series the times of each of the detected pulses for successive heartbeats.
Claim 30
Dependent Claim 64 words
Apparatus for measuring selected instantaneous patient heart pulse parameters comprising: means for taking heartbeat readings on the patient; means for detecting at least two of the P, R and T pulses for each heartbeat; means for determining the time at which each detected pulse occurs; and means for storing as a time series the times of each of the detected pulses for successive heartbeats.
Claim 31
Dependent Claim 19 words
Apparatus as claimed in claim 27 including means for storing amplitude for each pulse for which time is stored.
Claim 32
Dependent Claim 21 words
Apparatus as claimed in claim 27 wherein the means for storing stores the P, R and T pulses of each heartbeat.
Claim 33
Dependent Claim 32 words
Apparatus as claimed in claim 29 including means for converting the stored pulse times into heartrates for at least one of P-P, R-R, T-T, P-R, R-T, T-P, T-R, R-P and P-T heartrates.
Claim 34
Dependent Claim 31 words
Apparatus as claimed in claim 29 including means for converting the stored pulse times into heartrates for at least one of P-P, T-T, P-R, R-T, T-P, T-R, R-P and P-T heartrates.
Claim 35
Dependent Claim 31 words
Apparatus as claimed in claim 27 wherein said means for detecting includes means for deriving matched filters from the readings, and means for utilizing the matched filters in the detection process.
Claim 36
Dependent Claim 44 words
Apparatus as claimed in claim 27 wherein said means for detecting includes means for detecting the R pulse for the heartbeat, means for scanning back for the P pulse for the heartbeat, and means for scanning ahead for the T pulse for the heartbeat.
Claim 37
Dependent Claim 44 words
Apparatus for analyzing a measured heartbeat parameter comprising: means for converting the measured heartbeat parameter into a time series; means for deriving Indicator values δ j for the time series; and means for comparing the derived Indicator values against a corresponding stored Indicator value.
Claim 38
Dependent Claim 44 words
Apparatus for analyzing a measured heartbeat parameter comprising: means for converting the measured heartbeat parameter into a time series; means for deriving Indicator values δ j for the time series; and means for comparing the derived Indicator values against a corresponding stored Indicator value.
Claim 39
Dependent Claim 26 words
Apparatus as claimed in claim 34 wherein the measured heartbeat parameter is heartrate, the measured heartrate being converted into a time series of a selected heartrate.
Claim 40
Dependent Claim 29 words
Apparatus as claimed in claim 34 wherein the measured heartbeat parameter is peak voltage for each heartbeat, the measured peak voltages being converted into a peak voltage time series.
Claim 41
Dependent Claim 48 words
Apparatus as claimed in claim 34 wherein the means for deriving includes means for deriving a set of Differential Indicators δ j from the time series, and wherein the means for comparing includes means for comparing the derived set of Differential Indicators against corresponding stored Differential Indicator values.
Claim 42
Dependent Claim 29 words
Apparatus as claimed in claim 34 including means for notching the time series to eliminate unwanted detected peaks, said means for notching being operative before said mean for deriving.
Claim 43
Dependent Claim 80 words
Apparatus as claimed in claim 38 wherein said means for notching includes means for determining the means for the time series, means for determining the deviation from the mean for each of the time series, means for determining if the deviation from the mean for each entry exceeds a predetermined threshold, means for eliminating the value for each entry having a deviation from the mean exceeding the threshold, and means for substituting a selected average value for each eliminated value.
Claim 44
Dependent Claim 31 words
Apparatus as claimed in claim 34 including means for detrending the time series to remove low-frequency variations in the time series, the means for detrending being operative before the deriving means.
Claim 45
Dependent Claim 41 words
Apparatus as claimed in claim 40 wherein said means for detrending includes means for low-pass filtering the time series to isolate frequencies below a predetermined minimum threshold, and means for subtracting the results of the filtering step from the time series.

References Cited (Backward Citations)

US4478224A Cited
US4583553A Cited
US5092340A Cited
US4951680A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-01-10 1997-07-12 1998-01-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-01-10 2001-07-12 2002-01-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-01-10 2005-07-12 2006-01-11 $7700.00 Window Closed / Lapsed

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