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Effect of acupuncture at Shaofu acupoint on the cardiovascular system of healthy individuals

Saleem Ali Fouad, Al-Wahab Zainab, Al-Gailani Bassam Talib

Polish Journal of Medical Physics and Engineering

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2024

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Vol. 30, Iss. 3

127--131

EN

Background: Clinical and experimental observations show that acupuncture has been utilized as adjuvant therapy for a number of conditions, including hypertension, coronary heart disease, dysrhythmia, and myocardial infarction. Objective: To determine the cardiovascular (CV) reactivity in terms of blood pressure (BP), heart rate (HR), pulse wave velocity (PWV), and left ventricular ejection time (LVET) in response to acupuncture stimulation of the Shaofu (HT8) acupoint Methods: Resting systolic blood pressure (SBP) and diastolic blood pressure (DBP), HR, PWV, and LVET were recorded in 8 healthy subjects (age 20 years) in a supine position after 10 minutes of rest, 20 minutes after needle stimulation of Shaofu acupoint, and 10 minutes after removal of the acupuncture needle. Data were analyzed using one-way ANOVA. Results: SBP, DBP, HR, PWV, and LVET all remained on the same levels during acupuncture intervention and after the removal of the acupuncture needle relative to baseline values. Conclusion: Acupuncture at Shaofu acupoint has no CV effects.

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Validation of a new device for photoplethysmographic measurement of multi-site arterial pulse wave velocity

Sondej Tadeusz, Jannasz Iwona, Sieczkowski Krzysztof, Dobrowolski Andrzej, Obiała Karolina, Targowski Tomasz, Olszewski Robert

Biocybernetics and Biomedical Engineering

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2021

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Vol. 41, no. 4

1664--1684

EN

Pulse wave velocity (PWV) is commonly used for assessing arterial stiffness and it is a useful and accurate cardiovascular mortality predictor. Currently, many techniques and devices for PWV measurement are known, but they are usually expensive and require operator experience. One possible solution for PWV measurement is photoplethysmography (PPG), which is convenient, inexpensive and provides continuous PWV results. The aim of this paper is validation of a new device for PPG sensor-based measurement of multisite arterial PWV using a SphygmoCor XCEL (as the reference device) according to the recommendations of the Artery Society Guidelines (ASG). In this study, 108 subjects (56 men and 52 women, 20–91 years in 3 required age groups) were enrolled. The multi-site PWV was simultaneous measured by 7 PPG sensors commonly used in pulse oximetry in clinical settings. These sensors were placed on the forehead, and right and left earlobes, fingers and toes. Pulse transit time (PTT) was measured offline as the difference of time delay between two onsets of the pulse wave determined by the intersecting tangent method. The PWV was calculated by dividing the distance between PPG sensors by PTT. During PPG signals measurement, reference carotid to femoral PWV (cfPWV) was performed with a SphygmoCor XCEL system. The Pearson correlation coefficient (r) between the obtained PWV results was calculated. The Bland-Altman method was used to establish the level of agreement between the two devices. Mean difference (md) and standard deviation (SD) were also calculated. The multi-site PWV was highly correlated with accuracy at the ASG-defined level of ‘‘Acceptable” (md < 1.0 m/s and SD ≤ 1.5 m/s) with cfPWV: forehead - right toe (r = 0.75, md = 0.20, SD = 0.97), forehead - left toe (r = 0.79, md = 0.18, SD = 0.91), right ear - right toe (r = 0.79, md = 0.11, SD = 0.96), left ear - left toe (r = 0.75, md = 0.43, SD = 0.99), right ear - left toe (r = 0.78, md = 0.40, SD = 0.93), left ear - right toe (r = 0.78, md = 0.11, SD = 0.96), right finger - right toe (r = 0.66, md = 0.95, SD = 1.29), left finger - lefttoe (r = 0.67, md = 0.68, SD = 1.35). This study showed that PWV measured with the multisite PPG system, in relation to the obtained numerical values, correlated very well with that measured using the commonly known applanation tonometry method. However, it should be noted, that the measured PWV concerns the central and muscular part of the arterial tree while the cfPWV is only for the central one. The best results were obtained when the proximal PPG sensor was placed on the head (ear or forehead) and the distal PPG sensor on the toe. PPG sensors can be placed in many sites at the same time, which provides greater freedom of their configuration. Multi-site photoplethysmography is an alternative method for PWV measurement and creates new possibilities for the diagnostics of cardiovascular diseases.

3

Wyznaczanie czasu propagacji Fali tętna w oparciu o sygnały EKG i PPG

Sieczkowski Krzysztof, Dobrowolski Andrzej P., Sondej Tadeusz, Olszewski Robert

Przegląd Elektrotechniczny

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2019

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R. 95, nr 11

101--104

PL

W artykule przedstawiono nowatorską metodę pozwalającą na wyznaczanie czasów propagacji fali tętna, która bazuje na jednoczesnym pomiarze sygnałów EKG i PPG. Kluczowa dla proponowanego algorytmu dokładność wyznaczenia początkowego i końcowego punktu pomiarowego danego sygnału, silnie zależy od procedur wstępnego przetwarzania. Proponowane rozwiązanie opiera się na rozwijanej przez autorów metodzie korelacji aktualizowanego na bieżąco wzorca sygnału z aktualnie analizowanym fragmentem sygnału.

EN

In this article was presented a novel method for determining a pulse transit time, which is based on simultaneous measurement of ECG and PPG signals. The key to the proposed algorithm, the accuracy of determining the starting and ending measuring point of a given signal, strongly depends on the pre-processing procedures. The proposed solution is based on the method of correlation of the currently updated signal pattern with the currently analyzed fragment of signal, developed by the authors.

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The effect of measurement position on brachial–ankle pulse wave velocity

Shimawaki S., Toda M., Nakabayashi M., Sakai N.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 1

111--116

EN

Arterial stiffness measurements are primarily used for the early detection of arteriosclerosis. Methods and devices that can easily measure arterial stiffness at home are in demand. We propose a simple method for measuring brachial–ankle pulse wave velocity (baPWV) at home using a reclining chair and investigate the effects of positioning on baPWV measurement. We measured baPWV in 50 healthy men (21–70 years) in seven different measurement positions, including the supine position, sitting, sitting with the knees flexed at 45°, sitting with the knees flexed at 0°, reclining at 37°, reclining at 50°, and standing. BaPWV was significantly lower in the supine position (P < 0.01) than in the other positions. It was significantly higher in the sitting position (P < 0.01) than in the reclining position (37°). No changes in baPWV were seen changing the knee flexion angle alone while sitting. Strong correlations were also observed between baPWV in the supine position and that in other positions. We showed that baPWV in the supine position can be calculated by making corrections to baPWV measured in the sitting position at a reclining angle. Utilizing this corrected value would allow easy measurement at home using a reclining chair.

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Accuracy Comparison of Oscillometric and Electronic Palpation Blood Pressure Measuring Methods Using Intra-Arterial Method as a Reference

Sorvoja H., Myllylä R., Kärjä-Koskenkari P., Koskenkari J., Lilja M., Antero Kesäniemi Y.

Molecular and Quantum Acoustics

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2005

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Vol. 26

235-260

EN

This paper evaluates blood pressure measurements by the electronic palpation method (EP) and compares their accuracy to that of the oscillometric method (OSC) using average intra-arterial (IA) blood pressure as a reference. All of these three measurements were made simultaneously for each patient. The EP method, based on noninvasively detecting the amplitude of pressure pulsations in the radial artery, differs from the ordinary palpation method by allowing also diastolic pressure to be determined from the pulse delay produced by cuff pressure. In one test group, measurements were conducted on healthy volunteers in sitting and supine position during increasing and decreasing cuff pressure. Another group, comprising older, cardiac patients, was measured only in the supine position during cuff inflation. The results showed that the EP method was approximately as accurate as the OSC method with the healthy subjects and slightly more accurate with the cardiac patient group. The advantage of the EP method is that also the wave shape and velocity of arterial pressure pulses is available for further analysis like the assessment of arterial stiffness. Keywords: noninvasive, blood pressure, cuff, pulse transit time, pulse wave velocity