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Abstract Heart rhythm assessment is indispensable in diagnosis and management of many cardiac conditions and to study heart rate variability in healthy individuals. We present a proof-of-concept system for acquiring individual heart beats using smart speakers in a fully contact-free manner. Our algorithms transform the smart speaker into a short-range active sonar system and measure heart rate and inter-beat intervals (R-R intervals) for both regular and irregular rhythms. The smart speaker emits inaudible 18–22 kHz sound and receives echoes reflected from the human body that encode sub-mm displacements due to heart beats. We conducted a clinical study with both healthy participants and hospitalized cardiac patients with diverse structural and arrhythmic cardiac abnormalities including atrial fibrillation, flutter and congestive heart failure. Compared to electrocardiogram (ECG) data, our system computed R-R intervals for healthy participants with a median error of 28 ms over 12,280 heart beats and a correlation coefficient of 0.929. For hospitalized cardiac patients, the median error was 30 ms over 5639 heart beats with a correlation coefficient of 0.901. The increasing adoption of smart speakers in hospitals and homes may provide a means to realize the potential of our non-contact cardiac rhythm monitoring system for monitoring of contagious or quarantined patients, skin sensitive patients and in telemedicine settings.
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Non-Invasive, Continuous, Pulse Pressure Monitoring Method
Many individuals suffer from ailments such hypertension that require frequent health monitoring. Unfortunately, current technology does not possess the ability for unobtrusive, continuous monitoring. This paper proposes estimation of pulse pressure based on pulse transient time determined from one non-contact, and one contact sensor: Doppler radar for non-contact detection of heart beat, and piezoelectric finger pulse sensor. The time delay between heart beat and finger pulse was determined using MATLAB software, and pulse wave velocity (PWV) was calculated. Finally, subjects' pulse pressure estimated using PWV was found to be in good agreement with pulse pressure measured using an off the shelf sphygmomanometer by reading and taking difference of systolic and diastolic blood pressure.
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- Award ID(s):
- 1831303
- PAR ID:
- 10415719
- Date Published:
- Journal Name:
- 2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)
- Page Range / eLocation ID:
- 6574 to 6577
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/EMBC.2019.8857439
