Method and apparatus for measurement of autonomic nervous system function

Abstract

The invention analyzes relationships between factors, within a patient population, to identify autonomic dysfunction patterns. Patient test results are then compared with the identified patterns to determine the patient's autonomic function. The invention can continually amend the patient population with new test results to create increasingly accurate normative data sets from which a patient's autonomic function can be more accurately assessed. The invention may apply this concept in an application service provider model. An embodiment of the invention may use a novel method of identifying ECG R-waves. The method locates R-waves by searching for maximum slope values, in signals, that exceed threshold values. Another embodiment of the invention entails a non-provocative HRV test whereby certain time domain and frequency domain factors are analyzed to determine a patient's autonomic function.

1 . A method for assessing autonomic function comprising the steps of: 
 receiving background data from a population of patients wherein the population of patients is comprised of a first group of patients with a first state of autonomic function and a second group of patients with a second state of autonomic function;    receiving physiologic data from the population of patients;    determining from the physiologic data and the background data a first discriminant equation that discriminates between the first group of patients with the first state of autonomic function and the second group of patients with the second state of autonomic function;    receiving physiologic data from a new patient; and    inputting the physiologic data from the new patient into the first discriminant equation to provide a first autonomic ranking that is indicative of an autonomic function of the new patient.    
     
     
         2 . The method of  claim 1  wherein the physiologic data from the population of patients comprises at least one HRV measurement; wherein the HRV measurement is selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec, E/I Ratio, SD, NNmin SB, NNmax SB, VARmax, VARmean, RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF, VR and combinations thereof.  
     
     
         3 . The method of  claim 1  wherein the physiologic data from the new patient comprises at least one HRV measurement; wherein the HRV measurement is selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec, E/I RATIO, SD, NNmin SB, NNmax SB, VARmax, VARmean, RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF, VR and combinations thereof.  
     
     
         4 . The method of  claim 1  wherein the background data from the population of patients includes age and at least one selection from the group consisting of: race, gender, smoker status and health condition.  
     
     
         5 . The method of  claim 1  further comprising the steps of: 
 receiving background data from an additional population of patients wherein the additional population of patients is comprised of a third group of patients with a first state of autonomic function and a fourth group of patients with a second state of autonomic function;    receiving physiologic data from the additional population of patients;    determining from the physiologic data from the additional population of patients and the background data from the additional population of patients a second discriminant equation that discriminates between the third group of patients with the first state of autonomic function from the additional population of patients and the fourth group of patients with the second state of autonomic function from the additional population of patients; and    inputting the physiologic data from the new patient into the second discriminant equation to provide a second autonomic ranking that is indicative of an alternative autonomic function the new patient.    
     
     
         6 . The method of  claim 5  further comprising the step of indicating if the second autonomic ranking differs by a predetermined amount from the first autonomic ranking.  
     
     
         7 . The method of  claim 5  further comprising the step of displaying the first and second autonomic rankings in proximity to each other.  
     
     
         8 . The method of  claim 1  further comprising the steps of: 
 receiving background data from an additional population of patients wherein the additional population of patients is comprised of a third group of patients with a first state of autonomic function and a fourth group of patients with a second state of autonomic function;    receiving physiologic data from the additional population of patients;    determining from the physiologic data from the additional population of patients and the background data from the additional population of patients a second discriminant equation that discriminates between the third group of patients with the first state of autonomic function from the additional population of patients and the fourth group of patients with the second state of autonomic function from the additional population of patients;    receiving additional physiologic data from the new patient; and    entering the additional physiologic data from the new patient into the second discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the new patient.    
     
     
         9 . The method of  claim 8  further comprising the step of displaying the first and second autonomic rankings in proximity to each other.  
     
     
         10 . The method of  claim 1  further comprising the steps of: 
 receiving additional physiologic data from the new patient; and    inputting the additional physiologic data from the new patient into the first discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the new patient.    
     
     
         11 . The method of  claim 10  further comprising the step of indicating if the second autonomic ranking differs by a predetermined amount from the first autonomic ranking.  
     
     
         12 . The method of  claim 10  further comprising the step of displaying the first and second autonomic rankings in proximity to each other.  
     
     
         13 . The method of  claim 1  further comprising the step of classifying the first autonomic ranking as a condition.  
     
     
         14 . The method of  claim 13  wherein the condition is selected from the group consisting of: normal, abnormal, borderline and combinations thereof.  
     
     
         15 . The method of  claim 1  further comprising the step of classifying the first autonomic ranking as being indicative of an illness.  
     
     
         16 . The method of  claim 15  wherein the illness is selected from the group consisting of: diabetes, coronary artery disease, anxiety, depression, sudden cardiac death, myocardial infarction and hypertension.  
     
     
         17 . The method of  claim 1  wherein the first state of autonomic function is indicative of an illness; wherein the illness is selected from the group consisting of: diabetes, coronary artery disease, anxiety, depression, sudden cardiac death, myocardial infarction and hypertension.  
     
     
         18 . The method of  claim 1  wherein the second state of autonomic function is indicative of an illness; wherein the illness is selected from the group consisting of: diabetes, coronary artery disease, anxiety, depression, sudden cardiac death, myocardial infarction and hypertension.  
     
     
         19 . The method of  claim 1  further comprising the step of adding at least a portion of the additional physiologic data from the new patient to the physiologic data from the population of patients.  
     
     
         20 . One or more program storage media readable by a machine and containing instructions for performing the method contained in  claim 1 .  
     
     
         21 . The method of  claim 1  wherein the physiologic data from the new patient is obtained pursuant to the following steps: 
 receiving a first set of ECG data from the patient wherein the first set of ECG data is recorded while the patient is in a substantially reclined position and is breathing in a non-provoked manner;    measuring the first set of ECG data to obtain a first HRV measurement;    receiving a second set of ECG data from the patient wherein the second set of ECG data is recorded pursuant to one or more HRV tests; wherein the one or more HRV tests is selected from the group consisting of: Orthostatic test, Metronomic test and Valsalva test; and    measuring the second set of ECG data to obtain a second HRV measurement that is related to the one or more HRV tests, wherein the physiologic data from the new patient is comprised of the first HRV measurement and the second HRV measurement.    
     
     
         22 . The method of  claim 21  wherein the first HRV measurement is selected from the group consisting of: RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF and combinations thereof.  
     
     
         23 . The method of  claim 1  wherein the population of patients is further comprised of non-human patients.  
     
     
         24 . A system for assessing autonomic performance comprising: 
 a memory unit operable for storing one or more computer products for assessing autonomic performance; and    a processor coupled to the memory unit, wherein the processor executes the one or more computer products for performing the steps of:    receiving background data and HRV data from a population of patients having patients with a first state of autonomic function and patients with a second state of autonomic function;    performing discriminant analysis on the HRV data and the background data from the population of patients to determine a plurality of discriminant equations wherein each discriminant equation discriminates between the patients with the first state of autonomic function and the patients with the second state of autonomic function;    receiving background data and HRV data from a new patient;    selecting a discriminant equation from the plurality of discriminant equations in response to the background data from the new patient; and    inputting the HRV data from the new patient into the selected discriminant equation to provide an autonomic ranking that is indicative of an autonomic function of the new patient.    
     
     
         25 . The system of  claim 24  wherein the background data from the new patient includes age and at least one selection from the group consisting of: race, gender, smoker status and health condition.  
     
     
         26 . The system of  claim 24  wherein the processor executes the one or more computer products for performing the step of selecting the discriminant equation from the plurality of discriminant equations in a substantially automatic manner.  
     
     
         27 . The system of  claim 24  wherein the processor executes the one or more computer products for performing the additional step of classifying the autonomic ranking as a classification selected from the group consisting of: normal, abnormal, borderline and combinations thereof.  
     
     
         28 . The system of  claim 24  wherein the processor executes the one or more computer products for performing the step of classifying the autonomic ranking as being indicative of an illness.  
     
     
         29 . The system of  claim 28  wherein the illness is selected from the group consisting of: diabetes, coronary artery disease, anxiety, depression, sudden cardiac death, myocardial infarction and hypertension.  
     
     
         30 . The system of  claim 24  wherein the processor executes the one or more computer products for performing the steps of: 
 receiving additional HRV data from the new patient; and    inputting the additional HRV data from the new patient into the selected discriminant equation to provide a second autonomic ranking that is indicative of an alternative autonomic function of the new patient.    
     
     
         31 . The system of  claim 30  further comprising a display that displays both the first autonomic ranking and the second autonomic ranking.  
     
     
         32 . The system of  claim 24  wherein the processor executes the one or more computer products for performing the steps of: 
 receiving background data and HRV data from an additional population of patients having patients with a first state of autonomic function and patients with a second state of autonomic function;    performing discriminant analysis on the HRV data and the background data from the additional population of patients to determine a second plurality of discriminant equations wherein each of the second plurality of discriminant equations discriminates between the patients with the first state of autonomic function from the additional population of patients and the patients with the second state of autonomic function from the additional population of patients;    selecting a discriminant equation from the second plurality of discriminant equations in response to the background data from the new patient; and    inputting the HRV data from the new patient into the selected discriminant equation from the second plurality of discriminant equations to provide a second autonomic ranking that is indicative of an alternative autonomic function of the new patient.    
     
     
         33 . The system of  claim 32  further comprising a display that displays both the first autonomic ranking and the second autonomic ranking.  
     
     
         34 . The system of  claim 24  wherein the population of patients is further comprised of non-human patients.  
     
     
         35 . A method for assessing autonomic performance using a computer system, wherein the computer system includes one or more client computers, a server computer coupled to the one or more client computers, one or more memories coupled to the server computer, and one or more computer program products stored in the one or more memories, the method comprising: 
 storing a population data set, comprised of physiologic data and background data received from a population of patients wherein the population of patients is comprised of patients with a first state of autonomic function and patients with a second state of autonomic function, in the one or more memories;    using the one or more computer program products to process the population data set to determine a first discriminant equation that discriminates between the patients with the first state of autonomic function and the patients with the second state of autonomic function;    storing the first discriminant equation in the one or more memories;    using the one or more client computers to access the first discriminant equation; receiving physiologic data from a new patient;    and entering the physiologic data from the new patient into the first discriminant equation to produce a first autonomic ranking, wherein the first autonomic ranking is indicative of an autonomic function of the new patient.    
     
     
         36 . The method of  claim 35  wherein the step of entering the physiologic data from the new patient into the first discriminant equation may be performed in a manner; wherein the manner is selected from the group consisting of: manually and importing.  
     
     
         37 . The method of  claim 35  further comprising the step of adding the physiologic data from the new patient to the population data set.  
     
     
         38 . The method of  claim 35  further comprising: 
 storing an additional population data set, comprised of physiologic data and background data received from an additional population of patients wherein the additional population of patients is comprised of patients with a first state of autonomic function and patients with a second state of autonomic function, in the one or more memories;    using the one or more computer program products to process the additional population data set to determine a second discriminant equation that discriminates between the patients with the first state of autonomic function from the additional population of patients and the patients with the second state of autonomic function from the additional population of patients;    storing the second discriminant equation in the one or more memories;    accessing the second discriminant equation; and    entering the physiologic data from the new patient into the second discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the individual patient.    
     
     
         39 . The method of  claim 38  further comprising the step of indicating if the second autonomic ranking differs by a predetermined amount from the first autonomic ranking.  
     
     
         40 . The method of  claim 35  further comprising the step of displaying the first and second autonomic rankings in proximity to each other.  
     
     
         41 . The method of  claim 35  further comprising: 
 receiving additional physiologic data from the new patient;    entering the additional physiologic data from the new patient into the first discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the new patient.    
     
     
         42 . The method of  claim 41  further comprising the step of indicating if the second autonomic ranking differs by a predetermined amount from the first autonomic ranking.  
     
     
         43 . The method of  claim 41  further comprising the step of displaying the first and second autonomic rankings in proximity to each other.  
     
     
         44 . One or more program storage media readable by a machine and containing instructions for performing the method contained in  claim 35 .  
     
     
         45 . The method of  claim 30  wherein the population of patients is further comprised of non-human patients.  
     
     
         46 . A method of assessing autonomic function comprising: 
 receiving background data from a population of patients wherein the population of patients is comprised of patients with abnormal autonomic function and patients with normal autonomic function;    receiving ECG data from the population of patients;    measuring the ECG data from the population of patients to obtain one or more HRV parameters from the population of patients wherein the one or more HRV parameters from the population of patients are selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec, E/I Ratio, SD, NNmin SB, NNmax SB, VARmax, VARmean, RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF, VR and combinations thereof;    performing statistical discriminant analysis on the one or more HRV parameters from the population of patients and the background data from the population of patients to determine a plurality of discriminant equations wherein each discriminant equation discriminates between the patients with abnormal autonomic function and the patients with normal autonomic function;    receiving background data from a new patient;    receiving ECG data from the new patient;    measuring the ECG data from the new patient to obtain one or more HRV parameters from the new patient wherein the one or more HRV parameters are selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec, E/I Ratio, SD, NNmin SB, NNmax SB, VARmax, VARmean, RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF, VR and combinations thereof;    selecting a discriminant equation from the plurality of discriminant equations in response to the background data from the new patient;    inputting the one or more HRV parameters from the new patient into the selected discriminant equation to provide an autonomic ranking that is indicative of an autonomic function of the new patient.    
     
     
         47 . One or more program storage media readable by a machine and containing instructions for performing the method contained in  claim 46 .  
     
     
         48 . A method for assessing autonomic function comprising: 
 receiving HRV data from a patient that comprises at least one HRV measurement;    inputting the HRV data into a first discriminant equation to provide a first autonomic ranking that is indicative of an autonomic function of the patient, wherein the first discriminant equation discriminates between a first group of patients with a first state of autonomic function and a second group of patients with a second state of autonomic function.    
     
     
         49 . The method of  claim 48  wherein the HRV data comprises at least two HRV measurements.  
     
     
         50 . The method of  claim 48  wherein the HRV measurement is selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec and combinations thereof.  
     
     
         51 . The method of  claim 48  wherein the HRV measurement is selected from group consisting of: E/I Ratio, SD, NNmin SB, NNmax SB, VARmax, VARmean and combinations thereof.  
     
     
         52 . The method of  claim 48  wherein the HRV measurement is selected from group consisting of: RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF and combinations thereof.  
     
     
         53 . The method of  claim 48  further comprising the step of inputting the HRV data into a second discriminant equation to provide a second autonomic ranking that is indicative of an alternative autonomic function of the patient, wherein the second discriminant equation discriminates between a third group of patients with a first state of autonomic function and a fourth group of patients with a second state of autonomic function.  
     
     
         54 . The method of  claim 48  further comprising the following steps: 
 receiving additional HRV data from the patient that comprises at least one HRV measurement; and    inputting the additional HRV data into a second discriminant equation to provide a second autonomic ranking that is indicative of an alternative autonomic function of the patient, wherein the second discriminant equation discriminates between a third group of patients with a first state of autonomic function and a fourth group of patients with a second state of autonomic function.    
     
     
         55 . The method of  claim 48  further comprising the following steps: 
 receiving additional HRV data from the patient that comprises at least one HRV measurement; and    inputting the additional HRV data into the first discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the new patient.    
     
     
         56 . One or more program storage media readable by a machine and containing instructions for performing the method contained in  claim 48 .  
     
     
         57 . One or more computer program products, having one or more computer readable mediums with computer program logic recorded thereon, for assessing autonomic function, comprising: 
 programming operable for receiving background data from a population of patients wherein the population of patients is comprised of a first group of patients with a first state of autonomic function and a second group of patients with a second state of autonomic function;    programming operable for receiving physiologic data from the population of patients;    programming operable for determining from the physiologic data and the background data a first discriminant equation that discriminates between the first group of patients with the first state of autonomic function and the second group of patients with the second state of autonomic function;    programming operable for receiving physiologic data from a new patient; and    programming operable for inputting the physiologic data from the new patient into the first discriminant equation to provide a first autonomic ranking that is indicative of an autonomic function of the new patient.    
     
     
         58 . The one or more computer program products of  claim 57  wherein the physiologic data from the population of patients comprises at least one HRV measurement; wherein the HRV measurement is selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec, E/I Ratio, SD, NNmin SB, NNmax SB, VARmax, VARmean, RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF, VR and combinations thereof.  
     
     
         59 . The one or more computer program products of  claim 57  wherein the physiologic data from the new patient comprised at least one HRV measurement; wherein the HRV measurement is selected from the group consisting of: 30:15 Ratio, NNmin Standing, NNmax Standing, Tmax, Trec, E/I Ratio, SD, NNmin SB, NNmax SB, VARmax, VARmean, RMS-SD, NN, SDNN, TP, LFnorm, HFnorm, LF/HF, VLF, LF, HF, VR and combinations thereof.  
     
     
         60 . The one or more computer program products of  claim 57  wherein the background data from the population of patients includes age and a selection from the group consisting of: race, gender, smoker status and health condition.  
     
     
         61 . The one or more computer program products of  claim 57  further comprising: 
 programming operable for receiving background data from an additional population of patients wherein the additional population of patients is comprised of a third group of patients with a first state of autonomic function and a fourth group of patients with a second state of autonomic function;    programming operable for receiving physiologic data from the additional population of patients;    programming operable for determining from the physiologic data from the additional population of patients and the background data from the additional population of patients a second discriminant equation that discriminates between the third group of patients with the first state of autonomic function from the additional population of patients and the fourth group of patients with the second state of autonomic function from the additional population of patients; and    programming operable for inputting the physiologic data from the new patient into the second discriminant equation to provide a second autonomic ranking that is indicative of an alternative autonomic function the new patient.    
     
     
         62 . The one or more computer program products of  claim 61  further comprising programming operable for displaying the first and second autonomic rankings in proximity to each other.  
     
     
         63 . The one or more computer program products of  claim 57  further comprising: 
 programming operable for receiving background data from an additional population of patients wherein the additional population of patients is comprised of a third group of patients with a first state of autonomic function and a fourth group of patients with a second state of autonomic function;    programming operable for receiving physiologic data from the additional population of patients;    programming operable for determining from the physiologic data from the additional population of patients and the background data from the additional population of patients a second discriminant equation that discriminates between the third group of patients with the first state of autonomic function from the additional population of patients and the fourth group of patients with the second state of autonomic function from the additional population of patients;    programming operable for receiving additional physiologic data from the new patient; and    programming operable for entering the additional physiologic data from the new patient into the second discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the new patient.    
     
     
         64 . The one or more computer program products of  claim 63  further comprising programming operable for displaying the first and second autonomic rankings in proximity to each other.  
     
     
         65 . The one or more computer program products of  claim 57  further comprising: 
 programming operable for receiving additional physiologic data from the new patient; and    programming operable for inputting the additional physiologic data from the new patient into the first discriminant equation to produce a second autonomic ranking, wherein the second autonomic ranking is indicative of an alternative autonomic function of the new patient.    
     
     
         66 . The method of  claim 65  further comprising programming operable for displaying the first and second autonomic rankings in proximity to each other.