System and Method for Deriving a Pulse Wave Velocity-Blood pressure Transform

1 . A method for deriving a pulse wave velocity-blood pressure (PWV-BP) transform, the method comprising:

providing a general population PWV-BP transform comprising an average population correlation of PWV measurements to BP measurements, where a selected average population shares common characteristics with a selected first individual;

determining the validity of a personal PWV-BP transform, where the personal PWV-BP transform is based upon PWV and BP measurements for the first individual; and,

when the personal PWV-BP transform is determined to be invalid, using the general population PWV-BP to correlate a current PWV measurement for the first individual, to an estimated BP value for the first individual.

2 . The method of claim 1 further comprising:

simultaneously taking at least a first PWV measurement and a first BP measurement for the first individual;

modifying the general population PWV-BP transform using the at least the first PWV measurement and the first BP measurement; and,

saving the modified general population PWV-BP transform as an updated general population PWV-BP transform.

3 . The method of claim 2 further comprising:

taking a plurality of simultaneous PWV measurements and BP measurements for the first individual; and,

establishing the personal PWV-BP transform in response to the plurality of PWV and BP measurements.

4 . The method of claim 3 further comprising:

when the personal PWV-BP transform is determined to be valid, using the personal PWV-BP transform to correlate the current PWV measurement for the first individual, to the BP estimate for the first individual.

5 . The method of claim 4 wherein determining the validity of the personal PWV-BP transform includes determining invalidity when the current PWV measurement fails to meet a statistical limit derived from the current PWV measurement for the first individual and the plurality of simultaneous PWV measurements and BP measurements for the first individual.

6 . The method of claim 5 wherein determining the validity of the personal PWV-BP transform includes determining invalidity when the plurality of simultaneous PWV measurements and BP measurements for the first individual fail to meet a statistical limit.

7 . The method of claim 6 wherein taking the plurality of simultaneous PWV measurements and BP measurements for the first individual includes collecting a plurality of PWV-to-BP data points, cross-referenced to timestamps; and,

wherein establishing the personal PWV-BP transform includes establishing the personal PWV-BP transform in consideration of the PWV-to-BP data point timestamps, and a PWV-to-BP data point count.

8 . The method of claim 3 wherein establishing the personal PWV-BP transform includes collecting a PWV measurement as a statistical mean over many arterial pulses within the time interval of the PWV measurement.

9 . The method of claim 8 wherein taking the plurality of simultaneous PWV measurements and BP measurements for the first individual includes collecting a sample set with PWV-to-BP data points, cross-referenced to timestamps, where the period of time between timestamps is greater than a first period of time.

10 . The method of claim 9 wherein collecting the plurality of PWV-to-BP data points includes collecting PWV-to-BP data points for a plurality of physical and mental conditions for the first individual.

11 . A device for correlating pulse wave velocity (PWV) and blood pressure (BP) measurements, the device comprising:

a PWV measurement interface comprising an electrocardiogram (ECG) sensor and a photoplethysmography (PPG) sensor for measuring ECG and PPG signals;

a processor:

a non-transitory memory including:

a general population PWV-BP transform file with an average population correlation of PWV measurements to BP measurements, where a selected average population shares common characteristics with a selected first individual;

a personal PWV-BP transform file, where the personal PWV-BP transform file is based upon PWV and BP measurements for a first individual; and,

a screening application enabled as a sequence of processor instructions for determining the validity of the personal PWV-BP transform file, the screening application selecting the general population PWV-BP transform file when the personal PWV-BP transform file is determined to be invalid, and using the general population PWV-BP file to correlate a current PWV measurement for the first individual, to an estimated BP value for the first individual.

12 . The device of claim 11 further comprising:

a BP port for accepting BP measurements;

wherein the screening application accepts data for at least a first PWV measurement and a first BP measurement, simultaneously taken for the first individual, and creates an updated general population PWV-BP transform file; and,

the non-transitory memory further comprising:

the updated general population PWV-BP transform file including the general population PWV-BP transform file as modified by at least the first PWV measurement and the first BP measurement.

13 . The device of claim 12 wherein the screening application accepts data for a plurality of simultaneous PWV measurements and BP measurements taken for the first individual, and creates the personal PWV-BP transform file in response to the plurality of PWV and BP measurements.

14 . The device of claim 13 wherein the screening application uses the personal PWV-BP transform file to correlate the current PWV measurement for the first individual, to a BP estimate for the first individual, when the personal PWV-BP transform file is determined to be valid.

15 . The device of claim 14 wherein the screening application determines the personal PWV-BP transform file to be invalid when the current PWV measurement fails to meet a statistical limit derived from the current PWV measurement and the plurality of simultaneous PWV measurements and BP measurements for the first individual.

16 . The device of claim 15 wherein the screening application determines the personal PWV-BP transform file to be invalid when the personal PWV-BP transform fails to meet a predetermined statistical limit derived from the plurality of simultaneous PWV measurements and BP measurements for the first individual.

17 . The device of claim 13 wherein the personal PWV-BP transform fib includes a plurality of PWV-to-BP data points, cross-referenced to timestamps; and,

wherein the screening application creates the personal PWV-BP transform file in response to the PWV-to-BP data point timestamps and a PWV-to-BP data point count.

18 . The device of claim 13 wherein the screening application creates the personal PWV-BP transform file by collecting a PWV measurement as a statistical mean over many arterial pulses within the time interval of the PWV measurement.

19 . The device of claim 13 wherein the personal PWV-BP transform file includes a PWV-to-BP sample set, with PWV-to-BP data points cross-referenced to timestamps, where the period of time between timestamps is greater than a first period of time: and,

wherein a sample set is collected for a plurality of physical and mental conditions for the first individual.