DOI QR코드

DOI QR Code

Smartphone-Attachable Vascular Compliance Monitoring Module

스마트폰 탈착형 혈관 탄성 모니터링 모듈

  • Se-Hwan Yang (Dept. of Medical IT Convergence Engineering, Kumoh National Institute of Technology) ;
  • Ji-Yong Um (Dept. of Medical IT Convergence Engineering, Kumoh National Institute of Technology)
  • 양세환 ;
  • 엄지용
  • Received : 2024.06.11
  • Accepted : 2024.06.27
  • Published : 2024.06.30

Abstract

This paper presents a smartphone-attachable vascular compliance monitoring module. The proposed sensor module measures photoplethysmogram (PPG) and reconstructs an accelerated PPG waveform. The feature points are extracted from the accelerated PPG waves, and vascular compliance is estimated using these extracted features. The module is powered via the smartphone's USB terminal and transmits the acquired waveforms along with vascular compliance values through Bluetooth. The transmitted waveforms and vascular compliance value are displayed through the smartphone application. This work proposes an assessment method for consistency of PPG instrumentation, and it was implemented in a processor of sensor module. The proposed sensor module can be easily attached to smartphone that does not support PPG instrumentation, providing simple measurment and numerical analysis of vascular compliance. To verify the performance of the implemented sensor module, we acquired vascular compliance and pulse pressure data from 29 subjects. Pulse pressure, which serves as a representative indicator of vascular compliance, was obtained using a commercial blood pressure monitor. The analysis results showed that the Pearson coefficient between vascular compliance and pulse pressure was 0.778, confirming a relatively high correlation between two metrics.

본 논문은 스마트폰 탈착형 혈관 탄성 모니터링 모듈을 제안한다. 제안하는 센서 모듈은 광용적맥파(photoplethysmogram, PPG)를 계측하고 가속도 맥파를 복원한다. 복원된 가속도 맥파로부터 특징점을 추출하며, 해당 특징점을 이용하여 혈관 탄성 수치를 추정한다. 해당 모듈은 스마트폰의 USB 단자를 통해 전원을 공급 받으며, 블루투스 방식으로 가속도 맥파 파형과 혈관 탄성 수치를 스마트폰으로 전송한다. 스마트폰으로 전송된 파형과 혈관 탄성 수치는 안드로이드 어플리케이션을 통해 화면에 디스플레이 된다. 본 연구는 PPG 계측의 일관성을 평가하는 기법을 제안하며, 해당 기법은 모듈의 프로세서 내에 구현되었다. 본 연구에서 개발한 혈관 탄성 모니터링 모듈은 PPG 신호의 계측 및 분석을 지원하지 않는 스마트폰에 쉽게 탈착이 가능한 형태로 적용이 가능하며, 혈관 탄성의 손쉬운 계측 및 수치 분석을 제공하는 특징을 지닌다. 구현된 혈관 탄성 모니터링 모듈의 성능 검증을 위해, 29명의 피험자를 대상으로 혈관 탄성 수치와 맥압을 측정하였다. 맥압은 상용 혈압계를 이용하여 획득하였으며, 해당 지표는 혈관 탄성을 나타내는 대표적 지표에 해당한다. 분석 결과, 제작된 혈관 탄성 모니터링 모듈로부터 획득한 혈관 탄성 수치와 맥압 간의 피어슨 상관계수는 0.778이며, 두 수치 간의 비교적 높은 상관 관계를 확인하였다.

Keywords

Acknowledgement

This research was supported by Kumoh National Institute of Technology(2022).

References

  1. M. Elgendi et al., "The use of photoplethysmography for assessing hypertension," npj Dig. Med., vol.2, no.60, 2019. DOI: 10.1038/s41746-019-0136-7
  2. X. Ding et al., "Pulse transit time based continuous cuffless blood pressure estimation: a new extension and a comprehensive evaluation," Sci. Rep., vol.7, pp.11554-11564, 2017. DOI: 10.1038/s41598-017-11507-3
  3. F. Sarhaddi et al., "A comprehensive accuracy assessment of Samsung smartwatch heart rate and heart rate variability," PLoS One, vol.17, no.12, 2022. DOI: 10.1371/journal.pone.0268361
  4. H. Y. Lee et al., "Smartphone / smartwatch-based cuffless blood pressure measurement:a position paper from the Korean Society of Hypertension," Clin. Hypertens. vol.27, no.4, 2021. DOI: 10.1186/s40885-020-00158-8
  5. Gallup Korea (2023, July 13). 2012-2023 Smartphone Usage & Brand Survey.
  6. M. Elgendi et al., "Detection of a and b waves in the acceleration photoplethysmogram," Biomed. Eng. Online, vol.13, no.1, 2014. DOI: 10.1186/1475-925X-13-139
  7. L. Wang et al., "Multi-Gaussian fitting for pulse waveform using weighted least squares and multi-criteria decision making method," Computers in Biology and Medicine, vol.43, no.11, 2013. DOI: 10.1016/j.compbiomed.2013.08.004
  8. A. Chirinos et al., "Large-artery stiffness in health and disease: JACC state-of-the-art review," Journal of the American College of Cardiology, vol.74, no.9, 2019. DOI: 10.1016/j.jacc.2019.07.012
  9. E. Wowern et al., "Digital photoplethysmography for assessment of arterial stiffness: repeatability and comparison with applanation tonometry," PLoS One, vol.10, no.8, Aug. 2015. DOI: 10.1371/journal.pone.0135659
  10. S.-W. Kim et al., "Comparison of peripheral vascular compliance between normal and diabetic group using second derivative of photoplethysmogram," Journal of the Institute of Electronics Engineers of Korea. SC, vol.44, no.4, pp.15-20, 2007.
  11. M. Theodor et al., "Implantable acceleration plethysmography for blood pressure determination," IEEE EMBS, pp.4038-4041, 2013. DOI: 10.1109/EMBC.2013.6610431
  12. Chung-Luyl Lee, and Kyung-Ho Kim, "A study on estimate vascular compliance using acceleration photoplethysmogram," The Transactions of the Korean Institute of Electrical Engineers, vol.62, no.6, pp.840-844, 2013.
  13. K. Takazawa et al., "Assessment of vasoactive agents and vascular aging by the second derivative of photoplethysmogram waveform," Hypertension, vol.32, no.2, pp.365-370, 1998. DOI: 10.1161/01.hyp.32.2.365
  14. R. E. Klabunde, Cardiovascular Physiology Concepts. Indianapolis, IN, USA, Wolters Kluwer Health, 2020.
  15. J. Joseph et al., "Technical validation of ARTSENS - an image free device for evaluation of vascular stiffness," IEEE J. Transl., Eng., Health Med., vol.3, Art. no.1900213, 2015. DOI: 10.1109/JTEHM.2015.2431471