Extraction and Evaluation of Discriminative Indexes of the Wearing Condition for High-Precision Blood Pressure Pulse Wave Measurement

Q: What is the clinical evidence from this study?

Population: Healthy volunteer for blood pressure pulse wave measurement (n=1). Intervention: Discriminant index (LF/HF ratio of low-frequency to high-frequency blood pressure pulse wave components) using a prototype MEMS 3-axis force sensor arterial tonometry device vs. Amplitude of the blood pressure pulse wave (AP). Primary outcome: Correlation coefficient with blood pressure pulse wave amplitude (AP) and coefficient of variation across 20 repeated wearing experiments (R = 0.879; CV reduced by 12.8%).

Q: What does this research mean for the field?

The proposed low-frequency to high-frequency ratio (LF/HF) discriminant index strongly correlates with pulse wave amplitude (R = 0.879) while reducing coefficient of variation by 12.8% when evaluating arterial tonometry device wearing conditions. Novelty: ClaimNovelty.METHODOLOGICAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

Yosuke Osawa; Tetsuji DOHI

doi:10.3390/mi13050679

April 27, 2022MicromachinesOpen Access

Extraction and Evaluation of Discriminative Indexes of the Wearing Condition for High-Precision Blood Pressure Pulse Wave Measurement

View Full Paper

Ask AI

Bookmark

Share

Key result

Novel LF/HF discriminant index reduces arterial tonometry measurement variability by ~13%.

R = 0.879; CV reduced by 12.8%
n=1

Figures

Why the study?

Accurate arterial tonometry requires proper device wearing, but evaluating wearing conditions using pulse wave amplitude has been complicated by large variability.

Does the ratio of low-frequency to high-frequency blood pressure pulse wave components (LF/HF) reduce variability compared to pulse wave amplitude (AP) when evaluating the wearing condition of a radial arterial tonometry blood pressure device?

Key Points

To develop and validate a frequency-based discriminant index for accurately evaluating the wearing condition and contact pressing amount of an arterial tonometry pulse wave measurement device.
Fabricated a prototype device comprising MEMS 3-axis force sensors, a 3-axis push-in adjustment mechanism, a fixed jig, and a signal processing board.
Conducted wrist pulse wave measurements on a healthy 25-year-old male subject, incrementally increasing sensor displacement by 1 mm every 20 seconds.
Calculated the ratio of low-frequency (LF) to high-frequency (HF) components using Fourier transform and evaluated index stability across 20 repeated wearing experiments.
The correlation coefficient between the LF/HF discriminant index and pulse wave amplitude reached a peak of R = 0.924 in initial testing and stabilized at R = 0.879 across 20 experiments at a cut-off frequency of 7.3 Hz.
The coefficient of variation for the LF/HF index was 0.183 compared to 0.210 for pulse wave amplitude, reflecting a 12.8% reduction in measurement variability.

Structured PICO

Does the ratio of low-frequency to high-frequency blood pressure pulse wave components (LF/HF) reduce variability compared to pulse wave amplitude (AP) when evaluating the wearing condition of a radial arterial tonometry blood pressure device?

P

Population

1 healthy 25-year-old male subject who underwent 20 repeated blood pressure pulse wave measurement experiments in the resting sitting position.

I

Intervention

Evaluation of device wearing condition using a proposed discriminant index (LF/HF, the ratio of low-frequency component [2 < f <= fc Hz] to high-frequency component [f > fc Hz] with optimal cut-off frequency fc = 7.3 Hz) measured on the left radial artery via a prototype wristwatch-type arterial tonometry device with a MEMS 3-axis force sensor array.

C

Comparator

Conventional evaluation of device wearing condition using the maximum amplitude of the blood pressure pulse wave (AP).

O

Outcome

Correlation coefficient (R) between the discriminant index (LF/HF) and pulse wave amplitude (AP), and the coefficient of variation (CV) across 20 repetition experiments.surrogate

Main Result

Effect estimate: R = 0.879; CV reduced by 12.8%

Absolute Event Rate: 0.183% vs 0.21%

Limitations

Tested in only a single healthy 25-year-old male subject
Optimal cut-off frequency fc must be determined for each subject as it may vary with heart rate, respiration rate, or exercise state
Coefficient of variation tends to increase when the cut-off frequency fc increases
Experiments were conducted on only one healthy 25-year-old male subject
The optimal cut-off frequency fc must be determined for each individual because it is affected by heart rate, respiration rate, and physical activity
The coefficient of variation increases as the cut-off frequency value increases

Implication

Using the ratio of low-to-high frequency pulse wave components (LF/HF) provides a less variable metric than pulse wave amplitude for confirming proper sensor contact pressure in wearable radial tonometry blood pressure monitors.

Abstract

In this paper, we report a new discriminant index for evaluating the wearing condition of a blood pressure pulse wave measurement device with small variability. The prototype device consists of MEMS 3-axis force sensors, a 3-axis push-in adjustment mechanism, a fixed jig, and a signal processing board. The arterial tonometry method is used by this device to measure blood pressure pulse waves. However, to accurately measure the blood pressure pulse wave, the device must be appropriately worn. The evaluation of the wearing condition using the amplitude of the blood pressure pulse wave was complicated by the wearing process due to the large variability. Therefore, we propose the ratio of the blood pressure pulse wave component to the noise component as an index that can evaluate the wear condition of the device. The correlation coefficient between the discriminant index and the amplitude of the blood pressure pulse wave had a correlation coefficient of 0.879. Furthermore, the discriminant index reduced the coefficient of variation by 12.8%. Therefore, it was suggested that the discriminant index is an index that can evaluate the pressing amount, one of the wearing conditions of the blood pressure pulse wave measurement device with a small influence of variation.

Discussion

No takes yet. Share an insight, caveat, or question.

Cite This Study

Osawa et al. (2022) studied Healthy volunteer for blood pressure pulse wave measurement (n=1). Discriminant index (LF/HF ratio of low-frequency to high-frequency blood pressure pulse wave components) using a prototype MEMS 3-axis force sensor arterial tonometry device vs. Amplitude of the blood pressure pulse wave (AP) was evaluated on Correlation coefficient with blood pressure pulse wave amplitude (AP) and coefficient of variation across 20 repeated wearing experiments (R = 0.879; CV reduced by 12.8%). The proposed LF/HF discriminant index strongly correlated with pulse wave amplitude (R = 0.879) and reduced the coefficient of variation by 12.8% (0.183 vs 0.210) across 20 experiments.

synapsesocial.com/papers/6a749759b172e98d88f5405d https://doi.org/10.3390/mi13050679

View Full Paper

Ask AI

Bookmark

Share

Extraction and Evaluation of Discriminative Indexes of the Wearing Condition for High-Precision Blood Pressure Pulse Wave Measurement

Figures

Key Points

Structured PICO

Main Result

Limitations

Implication

Abstract

Discussion

Cite This Study

Extraction and Evaluation of Discriminative Indexes of the Wearing Condition for High-Precision Blood Pressure Pulse Wave Measurement

Figures

Key Points

Structured PICO

Main Result

Limitations

Implication

Abstract

Discussion

Cite This Study

Keep reading

Keep reading