Apparatus, system and method of determining a heart rate variability value
View Patent ↗A system for measuring heart rate variability (HRV) comprising 3 sub-systems: a data collection sub-system, a data analysis sub-system, and an output sub-system. A patient is connected to a heart monitoring device such as an ECG and the data collection sub-system records the patients heart beats, and an ECG chart is produced from which the patient's HRV value is derived by the data analysis sub-system. The present invention obtains the HRV value through calculation of a new parameter called relative density (RD). In accordance with the inventive method, data points are generated from the peak interval data of measured heart beats and the HRV relative density parameter (RD) is calculated by correlation between two subsets of data points.
1. A system for measuring heart rate variability (HRV), the system comprising:
a data generator to receive heartbeat information of a subject, the heartbeat information recorded by a data collector, said heartbeat information representing a series of heart beat intervals corresponding to said subject, said data generator is further to generate a plurality of data points based on the heartbeat information in the form of a two-dimensional representation having a coordinate system including a first axis and a second axis;
a data analyzer to identify two subsets of data points from said plurality of data points, said two subsets including a first subset of data points within a first axis-interval of said first axis, and a second subset of data points within a second axis-interval of said second axis;
a processor to calculate a subject-specific heart rate variability (HRV) relative density parameter (RD) value by dividing a first factor, which is based on said first subset of data points by a second factor, which is based on the second subset of data points; and
an output device, to output the subject-specific HRV RD value.
2. The system for measuring heart rate variability (HRV) according to claim 1 , wherein the output device is at least one device selected from the group consisting of: a screen, to display the subject-specific HRV RD value, a printer to print the subject-specific HRV RD value, an alarm to raise an audible sound, and an injector, to deliver an injection to a patient.
3. The system of claim 1 , wherein said subject-specific HRV RD value is configured to be compared to at least one predefined reference value corresponding to a heart condition, wherein a relationship between the subject-specific HRV RD value and the reference value is to represent a risk of said subject to suffer from said heart condition.
4. The system of claim 3 , wherein said subject-specific HRV RD value comprises a subject-specific dy/dx value, and said reference value comprises a reference dy/dx value.
5. The system of claim 4 , wherein said reference dy/dx value is lesser than 2.3.
6. The system of claim 4 , wherein said reference dy/dx value comprises a diagnostic dy/dx value configured to be compared to said subject-specific dy/dx value to diagnose said heart condition.
7. The system of claim 4 , wherein said reference dy/dx value comprises a prognostic dy/dx value configured to be compared to said subject-specific dy/dx value to provide a prognosis of said heart condition.
8. The system of claim 3 , wherein said heart condition comprises congestive heart failure.
9. The system of claim 3 , wherein said heart condition comprises Ventricular Tachcardia (VT).
10. The system of claim 1 , wherein one factor of said first and second factors comprises a dx factor and another factor of said first and second factors comprises a dy factor, the dx factor corresponding to an x-axis of a Cartesian coordinate system and the dy factor corresponding to a y-axis of the Cartesian coordinate system.
11. The system of claim 10 , wherein said dx factor is based on a first number of points within said first axis-interval, said first axis-interval comprises an interval along said x-axis having a maximal number of points compared to other axis-intervals along said x-axis, and wherein said dy factor is based on a second number of points within said second axis-interval, said second axis-interval comprises an interval along said y-axis having a maximal number of points compared to other axis-intervals along said y-axis.
12. The system of claim 1 , wherein said subject-specific HRV RD value is equal to the quotient of said first and second factor values.
13. A computer-based method for measuring heart rate variability (HRV), the method comprising:
receiving, by a computing device, heartbeat information of a subject, the heartbeat information recorded by a data collector, said heartbeat information representing a series of heart beat intervals corresponding to said subject;
generating, by said computing device, a plurality of data points based on the heartbeat information in the form of a two-dimensional representation having a coordinate system including a first axis and a second axis;
identifying, by said computing device, two subsets of data points from said plurality of data points, said two subsets including a first subset of data points within a first axis-interval of said first axis, and a second subset of data points within a second axis-interval of said second axis;
calculating, by said computing device, a subject-specific heart rate variability (HRV) relative density parameter (RD) value by dividing a first factor, which is based on said first subset of data points by a second factor, which is based on the second subset of data points; and
outputting the subject-specific HRV RD value.
14. The method of claim 13 , wherein said subject-specific HRV RD value is configured to be compared to at least one predefined reference value corresponding to a heart condition, wherein a relationship between the subject-specific HRV RD value and the reference value is to represent a risk of said subject to suffer from said heart condition.
15. The method of claim 14 , wherein said subject-specific HRV RD value comprises a subject-specific dy/dx value, and said reference value comprises a reference dy/dx value.
16. The method of claim 15 , wherein said reference dy/dx value is lesser than 2.3.
17. The method of claim 15 , wherein said reference dy/dx value comprises a diagnostic dy/dx value configured to be compared to said subject-specific dy/dx value to diagnose said heart condition.
18. The method of claim 13 , wherein one factor of said first and second factors comprises a dx factor and another factor of said first and second factors comprises a dy factor, the dx factor corresponding to an x-axis of a Cartesian coordinate system and the dy factor corresponding to a y-axis of the Cartesian coordinate system.
19. The method of claim 18 , wherein said dx factor is based on a first number of points within said first axis-interval, said first axis-interval comprises an interval along said x-axis having a maximal number of points compared to other axis-intervals along said x-axis, and wherein said dy factor is based on a second number of points within said second axis-interval, said second axis-interval comprises an interval along said y-axis having a maximal number of points compared to other axis-intervals along said y-axis.
20. The method of claim 13 , wherein said subject-specific HRV RD value is equal to the quotient of said first and second factor values.