-
Scientific Reports May 2024Arterial pulse wave velocity (PWV) is recognized as a convenient method to assess peripheral vascular stiffness. This study explored the clinical characteristics of hand...
Arterial pulse wave velocity (PWV) is recognized as a convenient method to assess peripheral vascular stiffness. This study explored the clinical characteristics of hand PWV (hPWV) and hand pulse transit time (hPTT) in healthy adults (sixty males = 42.4 ± 13.9 yrs; sixty-four females = 42.8 ± 13.9 yrs) voluntarily participated in this study. The arterial pulse waveform and the anatomical distance from the radial styloid process to the tip of the middle finger of both hands were recorded in the sitting position. The hPWV was calculated as the traversed distance divided by hPTT between those two points. Male subjects showed significantly greater hPWV, systolic blood pressure, and pulse pressure than age-matched female subjects, while the hPTT was not significantly different between genders. Multiple linear regression analysis showed that gender is a common determinant of hPWV and hPTT, and that age and heart rate (HR) were negatively correlated with hPWV and hPTT, respectively. We conclude that male subjects have greater hPWV than female subjects. Ageing is associated with decreased hPWV, while increased HR is associated with a smaller hPTT. The hPWV and hPTT might be used as non-invasive indices to characterise the ageing and arterial stiffness of peripheral blood vessels.
Topics: Humans; Male; Female; Pulse Wave Analysis; Adult; Middle Aged; Hand; Vascular Stiffness; Blood Pressure; Heart Rate; Healthy Volunteers
PubMed: 38698185
DOI: 10.1038/s41598-024-60927-5 -
Journal of the American Heart... Feb 2022Background Beat-to-beat blood pressure variability (BPV) is associated with an increased risk of stroke but can be driven by both healthy physiological processes and...
Background Beat-to-beat blood pressure variability (BPV) is associated with an increased risk of stroke but can be driven by both healthy physiological processes and failure of compensatory mechanisms. Blood pressure (BP) complexity measures structured, organized variations in BP, as opposed to random fluctuations, and its reduction may therefore identify pathological beat-to-beat BPV. Methods and Results In the prospective, population-based OXVASC (Oxford Vascular Study) Phenotyped Cohort with transient ischemic attack or minor stroke, patients underwent at least 5 minutes of noninvasive beat-to-beat monitoring of BP (Finometer) and ECG to derive the following: BPV (coefficient of variation) and complexity (modified multiscale entropy) of systolic BP and diastolic BP, heart rate variability (SD of R-R intervals), and baroreflex sensitivity (BRS; Welch's method), in low- (0.04-0.15 Hz) and high-frequency (0.15-0.4 Hz) bands. Associations between BPV or BP complexity with autonomic indexes and arterial stiffness were determined (linear regression), unadjusted, and adjusted for age, sex, and cardiovascular risk factors. In 908 consecutive, consenting patients, BP complexity was inversely correlated with BPV coefficient of variation (<0.001) and was similarly reduced in patients with hypertension or diabetes (<0.001). However, although BPV coefficient of variation had a U-shaped relationship with age, BP complexity fell systematically across age quintiles (quintile 1: 15.1 [14.0-16.1] versus quintile 5: 13.8 [12.4-15.1]) and was correlated with markers of autonomic dysfunction (heart rate variability SD of R-R intervals: = 0.20; BRS low frequency: 0.19; BRS high frequency: 0.26) and arterial stiffness (pulse wave velocity: -0.21; all <0.001), even after adjustment for clinical variables (heart rate variability SD of R-R intervals: 0.12; BRS low frequency and BRS high frequency: 0.13 and 0.17; and pulse wave velocity: -0.07; all <0.05). Conclusions Loss of BP complexity discriminates BPV because of pathological failure of compensatory mechanisms and may represent a less confounded and potentially modifiable risk factor for stroke.
Topics: Aging; Baroreflex; Biomarkers; Blood Pressure; Heart Rate; Humans; Prospective Studies; Pulse Wave Analysis; Stroke
PubMed: 35043657
DOI: 10.1161/JAHA.121.022865 -
BMC Infectious Diseases Oct 2023Pneumonia is the leading infectious cause of mortality worldwide and one of the most common lower respiratory tract infections that is contributing significantly to the...
BACKGROUND
Pneumonia is the leading infectious cause of mortality worldwide and one of the most common lower respiratory tract infections that is contributing significantly to the burden of antibiotic consumption. The study aims to identify the determinants of the progress of pulse rate, body temperature and time to recovery of pneumonia patients.
METHOD
A prospective cohort study design was used from Felege Hiwot referral hospital on 214 sampled pneumonia patients from March 01, 2022 up to May 31, 2022. The Kaplan-Meier survival estimate and Log-Rank test was used to compare the survival time. Joint model of bivariate longitudinal and time to event model was used to identify factors of longitudinal change of pulse rate and body temperature with time to recovery jointly.
RESULT
As the follow up time of pneumonia patient's increase by one hour the average longitudinal change of pulse rate and body temperature were decreased by 0.4236 bpm and 0.0119 [Formula: see text]. The average longitudinal change of pulse rate and body temperature of patients who lived in rural was 1.4602 bpm and 0.1550 [Formula: see text] times less as compared to urban residence. Patients who had dangerous signs are significantly increased the average longitudinal change of pulse rate and body temperature by 2.042 bpm and 0.6031 [Formula: see text] as compared to patients who had no dangerous signs. A patient from rural residence was 1.1336 times more likely to experience the event of recovery as compared to urban residence. The estimated values of the association parameter for pulse rate and body temperature were -0.4236 bpm and -0.0119 respectively, which means pulse rate and body temperature were negatively related with patients recovery time.
CONCLUSION
Pulse rate and body temperature significantly affect the time to the first recovery of pneumonia patients who are receiving treatment. Age, residence, danger sign, comorbidity, baseline symptom and visiting time were the joint determinant factors for the longitudinal change of pulse rate, body temperature and time to recovery of pneumonia patients. The joint model approach provides precise dynamic predictions, widespread information about the disease transitions, and better knowledge of disease etiology.
Topics: Humans; Body Temperature; Heart Rate; Prospective Studies; Pneumonia; Patients
PubMed: 37828463
DOI: 10.1186/s12879-023-08646-6 -
Sensors (Basel, Switzerland) Dec 2021Camera-based remote photoplethysmography (rPPG) is a low-cost and casual non-contact heart rate measurement method suitable for telemedicine. Several factors affect the...
Camera-based remote photoplethysmography (rPPG) is a low-cost and casual non-contact heart rate measurement method suitable for telemedicine. Several factors affect the accuracy of measuring the heart rate and heart rate variability (HRV) using rPPG despite HRV being an important indicator for healthcare monitoring. This study aimed to investigate the appropriate setup for precise HRV measurements using rPPG while considering the effects of possible factors including illumination, direction of the light, frame rate of the camera, and body motion. In the lighting conditions experiment, the smallest mean absolute R-R interval (RRI) error was obtained when light greater than 500 lux was cast from the front (among the following conditions-illuminance: 100, 300, 500, and 700 lux; directions: front, top, and front and top). In addition, the RRI and HRV were measured with sufficient accuracy at frame rates above 30 fps. The accuracy of the HRV measurement was greatly reduced when the body motion was not constrained; thus, it is necessary to limit the body motion, especially the head motion, in an actual telemedicine situation. The results of this study can act as guidelines for setting up the shooting environment and camera settings for rPPG use in telemedicine.
Topics: Algorithms; Heart Rate; Motion; Photoplethysmography; Telemedicine
PubMed: 34960451
DOI: 10.3390/s21248357 -
Science Advances Jun 2023By optically sensing absorption-induced photothermal effect, mid-infrared (IR) photothermal (MIP) microscope enables super-resolution IR imaging of biological systems in...
By optically sensing absorption-induced photothermal effect, mid-infrared (IR) photothermal (MIP) microscope enables super-resolution IR imaging of biological systems in water. However, the speed of current sample-scanning MIP system is limited to milliseconds per pixel, which is insufficient for capturing living dynamics. By detecting the transient photothermal signal induced by a single IR pulse through fast digitization, we report a laser-scanning MIP microscope that increases the imaging speed by three orders of magnitude. To realize single-pulse photothermal detection, we use synchronized galvo scanning of both mid-IR and probe beams to achieve an imaging line rate of more than 2 kilohertz. With video-rate speed, we observed the dynamics of various biomolecules in living organisms at multiple scales. Furthermore, by using hyperspectral imaging, we chemically dissected the layered ultrastructure of fungal cell wall. Last, with a uniform field of view more than 200 by 200 square micrometer, we mapped fat storage in free-moving and live embryos.
Topics: Animals; Caenorhabditis elegans; Cell Wall; Communications Media; Heart Rate; Microscopy, Confocal
PubMed: 37315131
DOI: 10.1126/sciadv.adg8814 -
Sensors (Basel, Switzerland) Feb 2024The use of radar technology for non-contact measurement of vital parameters is increasingly being examined in scientific studies. Based on a systematic literature search... (Review)
Review
The use of radar technology for non-contact measurement of vital parameters is increasingly being examined in scientific studies. Based on a systematic literature search in the PubMed, German National Library, Austrian Library Network (Union Catalog), Swiss National Library and Common Library Network databases, the accuracy of heart rate and/or respiratory rate measurements by means of radar technology was analyzed. In 37% of the included studies on the measurement of the respiratory rate and in 48% of those on the measurement of the heart rate, the maximum deviation was 5%. For a tolerated deviation of 10%, the corresponding percentages were 85% and 87%, respectively. However, the quantitative comparability of the results available in the current literature is very limited due to a variety of variables. The elimination of the problem of confounding variables and the continuation of the tendency to focus on the algorithm applied will continue to constitute a central topic of radar-based vital parameter measurement. Promising fields of application of research can be found in particular in areas that require non-contact measurements. This includes infection events, emergency medicine, disaster situations and major catastrophic incidents.
Topics: Heart Rate; Respiratory Rate; Radar; Signal Processing, Computer-Assisted; Algorithms; Vital Signs; Monitoring, Physiologic
PubMed: 38339721
DOI: 10.3390/s24031003 -
ELife Jul 2020Cardiovascular regulation is integral to life. Animal studies have identified both neural and endocrine pathways, by which the central nervous system adjusts cardiac...
Cardiovascular regulation is integral to life. Animal studies have identified both neural and endocrine pathways, by which the central nervous system adjusts cardiac output and peripheral vascular resistance to changing physiological demands. The outflow of these pathways is coordinated by various central nervous regions based on afferent information from baroreceptors, chemoreceptors, nociceptors, and circulating hormones, and is modulated by physiologic and behavioural state. In humans, however, knowledge on central cardiovascular regulation below the cortical level is scarce. Here, we show using functional MRI (fMRI) that at least three hypothalamic subsystems are involved in cardiovascular regulation in humans. The rhythmic behaviour of these systems corresponds to high and low frequency oscillations typically seen in blood pressure and heart rate variability.
Topics: Adult; Aged; Aged, 80 and over; Blood Pressure; Cardiovascular Physiological Phenomena; Central Nervous System; Female; Heart Rate; Humans; Male; Middle Aged; Monitoring, Physiologic
PubMed: 32720895
DOI: 10.7554/eLife.55316 -
JAMA Network Open May 2021Increasingly, individuals with atrial fibrillation (AF) use wearable devices (hereafter wearables) that measure pulse rate and detect arrhythmia. The associations of...
IMPORTANCE
Increasingly, individuals with atrial fibrillation (AF) use wearable devices (hereafter wearables) that measure pulse rate and detect arrhythmia. The associations of wearables with health outcomes and health care use are unknown.
OBJECTIVE
To characterize patients with AF who use wearables and compare pulse rate and health care use between individuals who use wearables and those who do not.
DESIGN, SETTING, AND PARTICIPANTS
This retrospective, propensity-matched cohort study included 90 days of follow-up of patients in a tertiary care, academic health system. Included patients were adults with at least 1 AF-specific International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) code from 2017 through 2019. Electronic medical records were reviewed to identify 125 individuals who used wearables and had adequate pulse-rate follow-up who were then matched using propensity scores 4 to 1 with 500 individuals who did not use wearables. Data were analyzed from June 2020 through February 2021.
EXPOSURE
Using commercially available wearables with pulse rate or rhythm evaluation capabilities.
MAIN OUTCOMES AND MEASURES
Mean pulse rates from measures taken in the clinic or hospital and a composite health care use score were recorded. The composite outcome included evaluation and management, ablation, cardioversion, telephone encounters, and number of rate or rhythm control medication orders.
RESULTS
Among 16 320 patients with AF included in the analysis, 348 patients used wearables and 15 972 individuals did not use wearables. Prior to matching, patients using wearables were younger (mean [SD] age, 64.0 [13.0] years vs 70.0 [13.8] years; P < .001) and healthier (mean [SD] CHA2DS2-VASc [congestive heart failure, hypertension, age ≥ 65 years or 65-74 years, diabetes, prior stroke/transient ischemic attack, vascular disease, sex] score, 3.6 [2.0] vs 4.4 [2.0]; P < .001) compared with individuals not using wearables, with similar gender distribution (148 [42.5%] women vs 6722 women [42.1%]; P = .91). After matching, mean pulse rate was similar between 125 patients using wearables and 500 patients not using wearables (75.01 [95% CI, 72.74-77.27] vs 75.79 [95% CI, 74.68-76.90] beats per minute [bpm]; P = .54), whereas mean composite use score was higher among individuals using wearables (3.55 [95% CI, 3.31-3.80] vs 3.27 [95% CI, 3.14-3.40]; P = .04). Among measures in the composite outcome, there was a significant difference in use of ablation, occurring in 22 individuals who used wearables (17.6%) vs 37 individuals who did not use wearables (7.4%) (P = .001). In the regression analyses, mean composite use score was 0.28 points (95% CI, 0.01 to 0.56 points) higher among individuals using wearables compared with those not using wearables and mean pulse was similar, with a -0.79 bpm (95% CI -3.28 to 1.71 bpm) difference between the groups.
CONCLUSIONS AND RELEVANCE
This study found that follow-up health care use among individuals with AF was increased among those who used wearables compared with those with similar pulse rates who did not use wearables. Given the increasing use of wearables by patients with AF, prospective, randomized, long-term evaluation of the associations of wearable technology with health outcomes and health care use is needed.
Topics: Adult; Aged; Atrial Fibrillation; Facilities and Services Utilization; Female; Follow-Up Studies; Health Services; Heart Rate; Humans; Male; Middle Aged; Monitoring, Physiologic; Propensity Score; Retrospective Studies; Self-Management; Tertiary Healthcare; Utah; Wearable Electronic Devices
PubMed: 34042996
DOI: 10.1001/jamanetworkopen.2021.5821 -
Revista Da Escola de Enfermagem Da U S P Sep 2019To evaluate cardiorespiratory alterations due to a single session of hyperbaric oxygen therapy. (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To evaluate cardiorespiratory alterations due to a single session of hyperbaric oxygen therapy.
METHOD
Randomized study with patients: a control group and hyperbaric oxygen therapy. Evaluations occurred in the beginning, during, and after exposure to pure oxygen above atmosphere for 2 hours. Systemic blood pressure, peripheral oxygen saturation, pulse rate, lung volume and lung capacity, and maximal inspiratory and expiratory pressures were evaluated. Peripheral oxygen saturation, pulse rate, and systemic blood pressure were evaluated during the pressurizing in the first hour. Data were evaluated by means of ANOVA, Mann-Whitney, and independent t-test (p<0.05).
RESULTS
A total of 14 adult patients were evaluated. In the group under therapy (seven subjects), aged: 49.57±14.59 years, there was a decrease in the pulse rate of 16 beats per minute after 35 minutes of therapy (intragroup analysis), and the peripheral oxygen saturation was higher within the same period compared to the control group.
CONCLUSION
The hyperbaric oxygen therapy promotes cardiorespiratory alterations with the increase of the peripheral oxygen saturation and decrease of the pulse rate, without altering blood pressure levels and the strength, volumes, and respiratory capacities.
Topics: Adult; Aged; Blood Pressure; Female; Heart Rate; Humans; Hyperbaric Oxygenation; Male; Middle Aged; Oxygen
PubMed: 31508730
DOI: 10.1590/S1980-220X2017051503469 -
Sensors (Basel, Switzerland) Aug 2019Heart rate measurement has become one of the most widely used methods of monitoring the intensity of physical activity. The purpose of this study was to assess whether...
Heart rate measurement has become one of the most widely used methods of monitoring the intensity of physical activity. The purpose of this study was to assess whether in-ear photoplethysmographic (PPG) pulse rate (PR) measurement devices represent a valid alternative to heart rate derived from electrocardiography (ECG), which is considered a gold standard. Twenty subjects (6 women, 14 men) completed one trial of graded cycling under laboratory conditions. In the trial, PR was recorded by two commercially available in-ear devices, the Dash Pro and the Cosinuss°One. They were compared to HR measured by a Bodyguard2 ECG. Validity of the in-ear PR measurement devices was tested by ANOVA, mean absolute percentage errors (MAPE), intra-class correlation coefficient (ICC), and Bland-Altman plots. Both devices achieved a MAPE ≤5%. Despite excellent to good levels of agreement, Bland-Altman plots showed that both in-ear devices tend to slightly underestimate the ECG's HR values. It may be concluded that in-ear PPG PR measurement is a promising technique that shows accurate but imprecise results under controlled conditions. However, PPG PR measurement in the ear is sensitive to motion artefacts. Thus, accuracy and precision of the measured PR depend highly on measurement site, stress situation, and exercise.
Topics: Adult; Ear; Electrocardiography; Exercise; Female; Heart Rate; Humans; Male; Middle Aged; Photoplethysmography
PubMed: 31438600
DOI: 10.3390/s19173641