US 11,653,844 B2
Risk determination of coronary artery disease
Samuel Emil Schmidt, Aalborg (DK)
Assigned to ACARIX A/S, Kgs Lyngby (DK)
Appl. No. 16/759,038
Filed by ACARIX A/S, Kgs Lyngby (DK)
PCT Filed Oct. 25, 2018, PCT No. PCT/EP2018/079263
§ 371(c)(1), (2) Date Apr. 24, 2020,
PCT Pub. No. WO2019/081630, PCT Pub. Date May 2, 2019.
Claims priority of application No. 17198552 (EP), filed on Oct. 26, 2017.
Prior Publication US 2020/0367771 A1, Nov. 26, 2020
Int. Cl. A61B 5/024 (2006.01); A61B 5/0255 (2006.01); A61B 5/00 (2006.01); A61B 7/04 (2006.01)
CPC A61B 5/02405 (2013.01) [A61B 5/0255 (2013.01); A61B 5/7275 (2013.01); A61B 7/045 (2013.01)] 18 Claims
OG exemplary drawing
 
15. A system for indicating a risk for coronary artery disease (CAD) for a person, wherein the system comprises:
a microphone configured for obtaining a recording of heart sounds from the person's heart when placed on the person's chest; and
a processor operatively connected to the microphone and configured, when programmed by executable instructions, to:
(a) identify a plurality of heart sounds in the recording of heart sounds;
(b) obtain a plurality of segments from the recording of heart sounds based on the plurality of heart sounds, wherein each segment covers at least a portion of a heart cycle including a diastole;
(c) determine a frequency power measure (FPM) based on a signal strength of a first frequency window of a period in the diastole of a first number of segments of the plurality of segments, and a signal strength of a second frequency window of the period in the diastole, wherein the second frequency window has a low cutoff that is above a high cutoff of the first frequency window, wherein the FPM is determined by: (1) determining a first sum based on the sum of the energy in the first frequency window of the first number of segments; (2) determining a second sum based on the sum of the energy in the second frequency window of the first number of segments; and (3) determining the frequency power measure (FPM) based on one of a ratio (FPR) between the first sum and the second sum, and the relative magnitude of the first sum and the second sum;
(d) determine an amplitude of a fourth heart sound (S4Amp) based on the plurality of heart sounds and the plurality of segments;
(e) determine an indication of a heart rate variability (HRV) based on the plurality of heart sounds; and
(f) determine an indication of the risk for coronary artery disease (CAD) based on the frequency power measure (FPM), the amplitude of the fourth heart sound (S4Amp), and the indication of the heart rate variability (HRV).