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Hypertension Research : Official... Apr 2023
Topics: Humans; Cardiovascular Diseases; Natriuretic Peptide, Brain; Heart Rate; Risk Factors; Hypertension; Blood Pressure; Heart Disease Risk Factors
PubMed: 36697875
DOI: 10.1038/s41440-023-01186-1 -
IEEE Journal of Biomedical and Health... May 2023We propose a novel framework to passively monitor pulse rate during the time spent by users on their personal mobile devices. Our framework is based on passively...
We propose a novel framework to passively monitor pulse rate during the time spent by users on their personal mobile devices. Our framework is based on passively capturing the user's pulse signal using the front-facing camera. Signal capture is performed in the background, while the user is interacting with the device as he/she normally would, e.g., watch movies, read emails, text, and play games. The framework does not require subject participation with the monitoring procedure, thereby addressing the well-known problem of low adherence with such procedures. We investigate various techniques to suppress the impact of spontaneous user motion and fluctuations in ambient light conditions expected in non-participatory environments. Techniques include traditional signal processing, machine learning classifiers, and deep learning methods. Our performance evaluation is based on a clinical study encompassing 113 patients with a history of atrial fibrillation (Afib) who are passively monitored at home using a tablet for a period of two weeks. Our results show that the proposed framework accurately monitors pulse rate, thereby providing a gateway for long-term monitoring without relying on subject participation or the use of a dedicated wearable device.
Topics: Female; Humans; Heart Rate; Atrial Fibrillation; Monitoring, Physiologic; Wearable Electronic Devices; Pulse
PubMed: 35939479
DOI: 10.1109/JBHI.2022.3197076 -
International Journal of Cardiology Jun 2013The usefulness of heart rate variability (HRV) as a clinical research and diagnostic tool has been verified in numerous studies. The gold standard technique comprises... (Comparative Study)
Comparative Study Review
BACKGROUND
The usefulness of heart rate variability (HRV) as a clinical research and diagnostic tool has been verified in numerous studies. The gold standard technique comprises analyzing time series of RR intervals from an electrocardiographic signal. However, some authors have used pulse cycle intervals instead of RR intervals, as they can be determined from a pulse wave (e.g. a photoplethysmographic) signal. This option is often called pulse rate variability (PRV), and utilizing it could expand the serviceability of pulse oximeters or simplify ambulatory monitoring of HRV.
METHODS
We review studies investigating the accuracy of PRV as an estimate of HRV, regardless of the underlying technology (photoplethysmography, continuous blood pressure monitoring or Finapresi, impedance plethysmography).
RESULTS/CONCLUSIONS
Results speak in favor of sufficient accuracy when subjects are at rest, although many studies suggest that short-term variability is somewhat overestimated by PRV, which reflects coupling effects between respiration and the cardiovascular system. Physical activity and some mental stressors seem to impair the agreement of PRV and HRV, often to an inacceptable extent. Findings regarding the position of the sensor or the detection algorithm are not conclusive. Generally, quantitative conclusions are impeded by the fact that results of different studies are mostly incommensurable due to diverse experimental settings and/or methods of analysis.
Topics: Electrocardiography; Heart Rate; Humans; Motor Activity; Photoplethysmography; Pulse; Rest
PubMed: 22809539
DOI: 10.1016/j.ijcard.2012.03.119 -
Psychosomatic Medicine Sep 2023Heart rate is a transdiagnostic correlate of affective states and the stress diathesis model of health. Although most psychophysiological research has been conducted in...
OBJECTIVE
Heart rate is a transdiagnostic correlate of affective states and the stress diathesis model of health. Although most psychophysiological research has been conducted in laboratory environments, recent technological advances have provided the opportunity to index pulse rate dynamics in real-world environments with commercially available mobile health and wearable photoplethysmography (PPG) sensors that allow for improved ecologically validity of psychophysiological research. Unfortunately, adoption of wearable devices is unevenly distributed across important demographic characteristics, including socioeconomic status, education, and age, making it difficult to collect pulse rate dynamics in diverse populations. Therefore, there is a need to democratize mobile health PPG research by harnessing more widely adopted smartphone-based PPG to both promote inclusivity and examine whether smartphone-based PPG can predict concurrent affective states.
METHODS
In the current preregistered study with open data and code, we examined the covariation of smartphone-based PPG and self-reported stress and anxiety during an online variant of the Trier Social Stress Test, as well as prospective relationships between PPG and future perceptions of stress and anxiety in a sample of 102 university students.
RESULTS
Smartphone-based PPG significantly covaries with self-reported stress and anxiety during acute digital social stressors. PPG pulse rate was significantly associated with concurrent self-reported stress and anxiety ( b = 0.44, p = .018) as well as prospective stress and anxiety at the subsequent time points, although the strength of this association diminished the farther away pulse rate got from self-reported stress and anxiety (lag 1 model: b = 0.42, p = .024; lag 2 model: b = 0.38, p = .044).
CONCLUSIONS
These findings indicate that PPG provides a proximal measure of the physiological correlates of stress and anxiety. Smartphone-based PPG can be used as an inclusive method for diverse populations to index pulse rate in remote digital study designs.
Topics: Humans; Heart Rate; Photoplethysmography; Smartphone; Prospective Studies; Anxiety
PubMed: 37409791
DOI: 10.1097/PSY.0000000000001178 -
Biomedical Engineering Online Jan 2018In the last few years, some studies have measured heart rate (HR) or heart rate variability (HRV) parameters using a video camera. This technique focuses on the...
BACKGROUND
In the last few years, some studies have measured heart rate (HR) or heart rate variability (HRV) parameters using a video camera. This technique focuses on the measurement of the small changes in skin colour caused by blood perfusion. To date, most of these works have obtained HRV parameters in stationary conditions, and there are practically no studies that obtain these parameters in motion scenarios and by conducting an in-depth statistical analysis.
METHODS
In this study, a video pulse rate variability (PRV) analysis is conducted by measuring the pulse-to-pulse (PP) intervals in stationary and motion conditions. Firstly, given the importance of the sampling rate in a PRV analysis and the low frame rate of commercial cameras, we carried out an analysis of two models to evaluate their performance in the measurements. We propose a selective tracking method using the Viola-Jones and KLT algorithms, with the aim of carrying out a robust video PRV analysis in stationary and motion conditions. Data and results of the proposed method are contrasted with those reported in the state of the art.
RESULTS
The webcam achieved better results in the performance analysis of video cameras. In stationary conditions, high correlation values were obtained in PRV parameters with results above 0.9. The PP time series achieved an RMSE (mean ± standard deviation) of 19.45 ± 5.52 ms (1.70 ± 0.75 bpm). In the motion analysis, most of the PRV parameters also achieved good correlation results, but with lower values as regards stationary conditions. The PP time series presented an RMSE of 21.56 ± 6.41 ms (1.79 ± 0.63 bpm).
CONCLUSIONS
The statistical analysis showed good agreement between the reference system and the proposed method. In stationary conditions, the results of PRV parameters were improved by our method in comparison with data reported in related works. An overall comparative analysis of PRV parameters in motion conditions was more limited due to the lack of studies or studies containing insufficient data analysis. Based on the results, the proposed method could provide a low-cost, contactless and reliable alternative for measuring HR or PRV parameters in non-clinical environments.
Topics: Adult; Algorithms; Body Mass Index; Equipment Design; Female; Heart Rate; Humans; Image Processing, Computer-Assisted; Male; Models, Theoretical; Motion; Photoplethysmography; Pulse; Signal Processing, Computer-Assisted; Video Recording
PubMed: 29378598
DOI: 10.1186/s12938-018-0437-0 -
Journal of the American Geriatrics... Nov 2022Increasing evidence links obstructive sleep apnea (OSA) to cognitive decline. Autonomic dysfunction assessed by heart rate variability is a promising early biomarker of...
BACKGROUND
Increasing evidence links obstructive sleep apnea (OSA) to cognitive decline. Autonomic dysfunction assessed by heart rate variability is a promising early biomarker of cognitive impairment in populations without major neurocognitive disorder (MND). We aimed to determine whether nocturnal pulse rate variability (PRV) extracted from oximetry signal and OSA severity could predict MND onset among older OSA patients.
METHODS
This study relied on data collected within the multicenter longitudinal Pays de la Loire Sleep Cohort, linked to health administrative data to identify new-onset MND. We included patients ≥60 years with newly diagnosed OSA, and no history of MND or atrial fibrillation. Cox proportional-hazards models were used to evaluate the association of MND with indices of PRV and OSA severity generated from sleep recordings.
RESULTS
After a median follow-up of 6.8 [4.7-9.4] years, 70 of 3283 patients (2.1%) had been diagnosed with MND. In multivariable Cox models, MND incidence was associated with age (p < 0.0001), depression (p = 0.013), and PRV assessed by the root mean square of the successive normal-to-normal (NN) beat interval differences (RMSSD; p = 0.008) and standard deviation of NN beat intervals (SDNN; p = 0.02). Patients with the highest quartile of RMSSD had a 2.3-fold [95%CI 1.11-4.92] higher risk of being diagnosed with MND. Indices of OSA and nocturnal hypoxia severity were not associated with MND.
CONCLUSIONS
Within a large clinic-based cohort of older patients with OSA, we found an association between oximetry-based indices of PRV and the onset of MND. Nocturnal oximetry-derived PRV indices could allow the early identification of OSA patients at higher risk of MND.
Topics: Humans; Aged; Heart Rate; Polysomnography; Sleep Apnea, Obstructive; Oximetry; Neurocognitive Disorders
PubMed: 35726128
DOI: 10.1111/jgs.17933 -
World Journal of Urology Jan 2023To identify the relationship between fluoroscopy pulse rate and absorbed radiation dose. We compared absorbed radiation dose with common proxy measurements such as...
PURPOSE
To identify the relationship between fluoroscopy pulse rate and absorbed radiation dose. We compared absorbed radiation dose with common proxy measurements such as fluoroscopy time and C-arm reported dose.
METHODS
Using a simulated patient model, 60 s fluoroscopy exposures were performed using pulse rates of 30, 8, 4, 2, and 1 pulse(s) per second. Each experiment was performed with both standard and low-dose settings using a GE OEC 9800 plus C-arm. Landauer nanoDot™ OSL dosimeters were used to measure the absorbed radiation dose.
RESULTS
Fluoroscopy pulse rate and absorbed radiation dose demonstrated a linear correlation for both standard (R = 0.995, p < 0.001) and low-dose (R = 0.998, p < 0.001) settings. For any given pulse rate, using the low-dose setting reduced absorbed radiation dose by 58 ± 2.8%. Fluoroscopy time demonstrated a linear relationship with absorbed radiation dose for both standard (R = 0.996, p < 0.001) and low-dose (R = 0.991, p < 0.001) settings, but did not change with use of the low-dose setting. C-arm reported radiation dose correlated linearly with absorbed dose (R = 0.999) but consistently under-estimated measured values by an average of 49 ± 3.5%. Using a combination of 1 pulse-per-second and low-dose fluoroscopy, absorbed dose was reduced by 97.7 ± 0.1% compared to standard dose and 30 pulse-per-second settings.
CONCLUSION
Absorbed radiation dose decreases linearly with fluoroscopy pulse rate during equivalent exposure times. Adjusting fluoroscopy pulse rate and utilizing low-dose settings significantly reduces overall absorbed radiation exposure by up to 98%.
Topics: Humans; Radiation Dosage; Heart Rate; Radiation Exposure; Fluoroscopy; Patients
PubMed: 36525105
DOI: 10.1007/s00345-022-04238-2 -
Journal of Medical Engineering &... Apr 2023Heart rate variability (HRV) extracted from the electrocardiogram (ECG) is an essential indicator for assessing the autonomic nervous system in clinical. Some scholars...
Heart rate variability (HRV) extracted from the electrocardiogram (ECG) is an essential indicator for assessing the autonomic nervous system in clinical. Some scholars have studied the feasibility of pulse rate variability (PRV) instead of HRV. However, there is little qualitative research in different body states. In this paper, the photoplethysmography (PPG) of postauricular and finger and the ECG of fifteen subjects were synchronously collected for comparative analysis. The eleven experiments were designed according to the daily living state, including the stationary state, limb movement state, and facial movement state. The substitutability of nine variables was investigated in the time, frequency, and nonlinearity domain by Passing Bablok regression and Bland Altman analysis. The results showed that the PPG of the finger was destroyed in the limb movement state. There were six variables of postauricular PRV, which showed a positive linear relationship and good agreement ( > 0.05, ratio 0.2) with HRV in all experiments. Our study suggests that the postauricular PPG could retain the necessary information of the pulse signal under the limb movement state and facial movement state. Therefore, postauricular PPG could be a better substitute for HRV, daily PPG detection, and mobile health than finger PPG.
Topics: Humans; Heart Rate; Healthy Volunteers; Photoplethysmography; Electrocardiography; Autonomic Nervous System
PubMed: 36794319
DOI: 10.1080/03091902.2023.2175061 -
Contact-Free Monitoring of Pulse Rate For Triage of Patients Presenting to the Emergency Department.The Journal of Emergency Medicine Dec 2021The evaluation of a patient's pulse rate (PR) plays a key role in emergency triage and is commonly measured in a contact-dependent way.
BACKGROUND
The evaluation of a patient's pulse rate (PR) plays a key role in emergency triage and is commonly measured in a contact-dependent way.
OBJECTIVE
Our aims were to evaluate a camera-based prototype application (CBPA) measuring PR in an emergency department (ED) as an alternative to the current contact-dependent method of pulse oximetry and to determine the correlation between CBPA and pulse oximetry in measuring PR.
METHODS
We simultaneously measured PR with CBPA and pulse oximetry as a reference method on a large group of ED walk-in patients. We then estimated correlation and agreement between the two methods, as well as the corresponding 95% confidence intervals.
RESULTS
In a convenience sample of 446 patients, the correlation between CBPA and pulse oximetry in measuring PR was 0.939 (95% confidence interval [CI] 0.927-0.949) and the intraclass correlation was 0.939 (95% CI 0.927-0.949).
CONCLUSIONS
Our study found that CBPA seems to be a viable alternative to the current method of measuring PR at triage. ClinicalTrials.gov identifier: NCT03393585.
Topics: Emergency Service, Hospital; Heart Rate; Humans; Oximetry; Triage
PubMed: 34474932
DOI: 10.1016/j.jemermed.2021.07.005 -
Scientific Reports Jan 2020Availability of daily continuous blood pressure (DCBP) has a strong impact to realization of healthy society. However, existing methods to obtain blood pressure of cuff... (Observational Study)
Observational Study
Availability of daily continuous blood pressure (DCBP) has a strong impact to realization of healthy society. However, existing methods to obtain blood pressure of cuff type and cuff-less types utilizing correlation with pulse waveform, pulse transit time or pulse rate; or computation of circulation model are not suitable to obtain DCBP. Here we implemented a method based on a simple circulatory system model using pulse rate measurement to overcome the limitations, and showed that it provides appropriate estimation of DCBP. The present model consists of a circulatory dynamic system model and an inverse model of a circulatory control system with input of pulse rate and six model parameters representing standard pulse rate, elasticity of systemic arteries, peripheral vascular resistance, and characteristics of resistance and stroke volume control. Validity of the DCBP estimation method was examined by preliminary experiment for one subject in four days and that for four subjects in one day. DCBP estimation was performed with 24-hour pulse rate measurement by a wearable device and sphygmomanometer measurement for parameter determination and verification. Mean absolute errors in systolic/diastolic pressures were appropriate ones for preliminary experiments with 9.4/6.4 mmHg in four days and 7.3/5.9 mmHg in five subjects.
Topics: Adult; Blood Pressure; Blood Pressure Monitoring, Ambulatory; Blood Pressure Monitors; Healthy Volunteers; Heart Rate; Humans; Male; Middle Aged; Models, Cardiovascular; Stroke Volume; Vascular Resistance; Wearable Electronic Devices; Young Adult
PubMed: 31996723
DOI: 10.1038/s41598-020-58367-y