Search Results (2,221)

In recent years, with the increased interest in smart home technology and the increased need to remotely monitor patients due to the pandemic, demand for contactless systems for vital sign measurements has also been on the rise. One of these kinds of systems are Doppler radar systems. Their design is composed of several choices that could possibly have a significant impact on their overall performance, more specifically those focused on the measurement of cardiac activity. This review, conducted using works obtained from relevant scientific databases, aims to understand the impact of these design choices on the performance of systems measuring either heart rate (HR) or heart rate variability (HRV). To that end, an analysis of the performance based on hardware architecture, carrier frequency, and measurement distance was conducted for works focusing on both of the aforementioned cardiac parameters, and signal processing trends were discussed. What was found was that the system architecture and signal processing algorithms had the most impact on the performance, with FMCW being the best performing architecture, whereas factors like carrier frequency did not have an impact.This means that newer systems can focus on cheaper, lower-frequency systems without any performance degradation, which will make research easier. Full article

Background: Myocardial infarction (MI) is a common emergency with high rates of morbidity and mortality. Current risk stratification scores for non-ST-elevation MI (NSTEMI) use subjective or delayed information. Heart rate variability was shown to correlate with prognosis following MI. This study aimed to evaluate ultra-short heart rate variability (usHRV) as a prognostic factor in NSTEMI patients. Methods: A retrospective analysis was performed on 183 NSTEMI patients admitted to Rambam Health Care Campus in 2014. usHRV measures, including the standard deviation of normal-to-normal intervals (SDNN) and root mean square of successive differences (RMSSD), were calculated. Logistic regression assessed whether clinical, laboratory, or usHRV parameters predicted severe in-hospital complications like heart failure (HF), atrial flutter/fibrillation (AFL/AF), ventricular tachycardia/fibrillation (VT/VF), and atrioventricular block (AVB). Both Cox and logistic regression were used for survival analysis. Results: Of 183 patients (71.6% male, mean age 67.1), 35 (19%) died within 2 years. In-hospital complications included 39 cases (21.3%) of HF, 3 cases (1.6%) of VT/VF, and 9 cases (4.9%) of AVB. Lower usHRV was significantly associated with higher mortality at 2 years and showed marginal significance at 90 days and 1 year. Increased usHRV was linked to a higher risk of in-hospital ventricular arrhythmia (VT/VF). Conclusions: Overall, this study is in agreement with previous research, showing a correlation between low usHRV and a higher mortality risk. However, the association between usHRV and the risk of VT/VF demands further investigation. More expansive prospective studies are needed to strengthen the observed associations. Full article

Background/Objectives: Smoking and hypertension are major contributors to cardiovascular diseases, with smoker hypertensives typically presenting with exacerbated health risks. These factors are associated with COVID-19 aggravation, but their cumulative impact in the context of this disease remains understudied. Our hypothesis was that hypertensive smokers display a more vulnerable health profile (versus non-smokers) upon hospital admission for COVID-19. Methods: This exploratory observational study compared the clinical profiles of hypertensive COVID-19 patients depending on their smoking status. Focusing on key cardiometabolic, blood, renal, hepatic, and inflammatory markers, this investigation included 100 hypertensive COVID-19 patients (50 smokers and 50 non-smokers) aged 50 and above. Logistic regression and Spearman’s correlations were used to identify significant predictors and relationships among variables. Results: Hypertensive smokers with COVID-19 were significantly more likely to exhibit higher heart rate (p = 0.047), left atrial size (p = 0.013) and diameter (p = 0.040), left ventricular end-systolic volume (p = 0.036), and interventricular septal thickness (p ≤ 0.001). These patients were also much more prone to display elevated CRP (p = 0.035) and hemoglobin (p = 0.011). The renal profiles of the smokers and non-smokers differed, with the smokers showing a significantly greater likelihood to have high serum urea (p = 0.036), but normal-to-low serum potassium (p = 0.011) and sodium (p ≤ 0.001). Their lipid profile was less favorable, with higher triglycerides (p ≤ 0.001), but lower HDL (p = 0.008). The strongest predictors of smoking status were interventricular septal thickness, triglycerides, and serum sodium. Conclusions: Hypertensive smokers admitted to the hospital with COVID-19 tend to exhibit a more adverse clinical profile, particularly in terms of cardiovascular remodeling, lipid imbalances, renal profile, and inflammation. These findings suggest that smoking exacerbates the effects of hypertension in the context of COVID-19, highlighting the need for more aggressive monitoring and management in this patient group. Full article

Background/Objectives: Chronic low back pain (CLBP) is highly prevalent and relevant in all medical fields. This study evaluated the safety and effectiveness of interdisciplinary fascia therapy (IFT) for CLBP, focusing on its potential to reduce pain intensity, disability, and regulate autonomic nervous system (ANS) activity. Methods: Nine participants with CLBP each underwent nine sessions of IFT, twice weekly. The intervention involved a 12-grip manual sequence targeting deep paravertebral myofascial structures, complemented by heart rate variability (HRV) biofeedback training twice daily for 15 min. Pain and quality-of-life measures were assessed using the Brief Pain Inventory (BPI) questionnaire at baseline, mid-treatment (4th session), and post-treatment (9th session). HRV metrics were monitored with a 24 h ECG Holter device before and after the treatment period. Statistical analyses included paired t-tests, Wilcoxon signed-rank tests, and Cohen’s d for effect size. Results: Significant reductions in pain levels were observed across all subjective BPI measures, including momentary, strongest, minimal, and average pain scores (p < 0.001), with 83% and 87% reductions in pain intensity and disability, respectively. Quality-of-life indicators such as mood, sleep, and enjoyment of life showed significant improvements (p < 0.001). While only one HRV metric (rMSSD) achieved statistical significance, other HRV measures indicated medium to large effect sizes, suggesting favorable trends in ANS regulation. Conclusions: IFT demonstrated significant effects on subjective BPI pain reduction and quality of life, alongside potential regulatory impacts on ANS activity in individuals with CLBP. These results support the use of IFT as an effective intervention for pain management in CLBP and ANS regulation, meriting further exploration. Full article

Stress responses can impact bladder cancer (BC) outcomes via immune–inflammatory pathway modulation. This study explores heart rate variability (HRV) associations with serum immune–inflammatory biomarkers, blood count inflammatory markers, and psychosocial self-report measures in patients versus healthy controls. The TREM-1 and TREM-2 expressions on peripheral blood monocytes were analysed via flow cytometry; serum inflammatory biomarkers by ELISA; HRV (5-min ECG) pre-tumour resection; blood counts by haematology analyser; and psychosocial factors by validated questionnaires. Patients exhibited altered immune–inflammatory profiles with increased TREM-1/TREM-2, sTREM-1, sTREM-1/sTREM-2 ratio, BDNF, MCP-1, and NLR, and reduced IFN-γ, IL-10, LMR, and PMR. HRV analysis indicated sympathetic dominance (SNS, Stress indices, ACmod) and reduced parasympathetic modulation (PNS index, SDNN, RMSSD, 2UV%, DCmod, SD1). Sympathetic HRV indices correlated positively with sTREM-1, sTREM-1/sTREM-2 ratio, fractalkine, and inflammatory markers (SII, NLR, PLR) and negatively with parasympathetic HRV indices—correlations absent in controls. Only in patients, reduced physical function and social support, and higher anxiety, depression, and fatigue, associated positively with sympathetic HRV indices and inflammatory markers. This study links immune–inflammatory markers, HRV parameters, and psychosocial factors in BC, suggesting that immune and autonomic variations may relate to unfavourable outcomes. Incorporating these assessments could help tailor more personalised treatment strategies for BC patients. Full article

Background: Impairment in autonomic activity is a prognostic marker in patients with heart failure (HF), and its involvement has been suggested in cardiovascular complications of obstructive sleep apnea syndrome (OSAS) and Cheyne–Stokes respiration (CSR). This prospective observational study aims to investigate the implications of sleep-disordered breathing (SDB) on hemodynamic regulation and autonomic activity in chronic HF patients. Methods: Chronic HF patients, providing confirmation of reduced ejection fraction (≤35%), underwent polysomnography, real-time hemodynamic, heart rate variability (HRV), and baroreceptor reflex sensitivity (BRS) assessments using the Task Force Monitor. BRS was assessed using the sequencing method during resting conditions and stress testing. Results: Our study population (n = 58) was predominantly male (41 vs. 17), with a median age of 61 (±11) yrs and a median BMI of 30 (±5) kg/m². Patients diagnosed with CSR were 13.8% (8/58) and 50.0% (29/58) with OSAS. No differences in the real-time assessment of hemodynamic regulation, heart rate variability, or baroreceptor reflex function were found between patients with OSAS, CSR, and patients without SDB. A subgroup analysis of BRS and HRV in patients with severe SDB (AHI > 30/h) and without SDB (AHI < 5) revealed numerically reduced BRS and increased LF/HF-RRI values under resting conditions, as well as during mental testing in patients with severe SDB. Patients with moderate-to-severe SDB had a shorter overall survival, which was, however, dependent upon age. Conclusions: Chronic HF patients with severe SDB may exhibit lower baroreceptor function and impaired cardiovascular autonomic function in comparison with HF patients without SDB. Full article

Body composition could influence exercise physiology. However, no one has ever studied the effect of visceral fat (VF) on heart rate (HR) trends during and after exercise by using bioimpedance analysis (BIA). This study aims to investigate BIA variables as predictors of HR trends during vigorous exercise. Ninety-six participants (age 22.5 ± 4.8 years) were included in the data analysis. After performing BIA, the HR was recorded at three time points: baseline HR (BHR), peak HR (PHR) at the end of vigorous exercise, and resting HR (RHR) 1 min after the end of the exercise. After BHR, a 30 s squat jump test was performed. Linear regression analysis showed the body fat percentage and VF as a predictor of HR recovery post-exercise (p < 0.01). However, body weight has no association with HR recovery (p > 0.05). On the other hand, BIA variables were not associated with the variation of HR from the baseline to the end of the exercise. The results show that higher VF is associated with a slower HR recovery. To schedule a training program, it would be safer to monitor visceral fat before prescribing recovery time. Full article

The head-up tilt (HUT) test assesses both cardiovascular autonomic regulation and cerebral autoregulation. This exploratory study examined age-related changes in cardiovascular and cerebrovascular responses during the HUT test in three healthy cohorts (young, middle-aged, and elderly). We recruited 2342 neurologist-diagnosed ‘normal’ individuals from 18 June 2014 to 25 February 2022. Cerebrovascular and cardiovascular responses were assessed during the HUT test, including cerebral blood flow velocity (CBFv) of the middle cerebral artery, systolic arterial pressure (SYS), diastolic arterial pressure (DIA), mean arterial pressure (MAP), pulse pressure (PP), heart rate (HR), stroke volume (SV), cardiac output (CO), and cerebrovascular conductance (CVCi). These variables were analyzed across three groups (young, middle-aged, and elderly) and three periods (resting, post-HUT, and recovery). Participants were stratified into three age groups: young (18–45 years; n = 384), middle-aged (46–59 years; n = 434), and elderly (≥60 years; n = 590). PP increased significantly with age, while CBFv and CVCi decreased significantly across the three periods. As measurements progressed, DIA and HR increased, and SV, CBFv, and CVCi decreased. This study enhances our understanding of age-related differences in cardiovascular and cerebrovascular responses to the HUT test. These insights may improve the clinical utility of the HUT test and guide outcome analysis across age groups. Full article

Background and Aims: Post-exercise recovery strategies include massage, low-intensity active exercise, thermal contrast, hydration, and nutritional and herbal approaches. These strategies aim to accelerate recovery, enhance performance, and optimise the physical training process. L-arginine (L-ARG) is the physiological precursor of nitric oxide (NO), a crucial mediator of vasodilation and the inhibition of platelet aggregation. A previous study reported that L-ARG supplementation could significantly reduce the systolic blood pressure (SBP) and diastolic blood pressure (DBP). This study aimed to investigate the effects of L-ARG on autonomic and cardiovascular recovery immediately following submaximal exercise. Methods and Results: Thirty-two healthy individuals were subjected to two experimental protocols. The first protocol included 60 min of rest, a treadmill warm-up, and load increments until reaching 80% of their maximum HR. Before this protocol, the subjects consumed 3 g of starch (placebo protocol). The second protocol was identical, but the subjects consumed 3 g of L-ARG. Heart rate recovery (HRR), heart rate variability (HRV), and blood pressure (BP) responses were assessed. No significant differences in HRR were found (p = 0.944) regarding the root mean square of successive differences in the RR interval (RMSSD30) of HRV (p = 0.562) or in the BP responses (mean arterial pressure (MAP), p = 0.687; pulse pressure (PP), p = 0.929) between the protocols. Conclusions: L-ARG supplementation did not significantly alter immediate post-exercise autonomic recovery in healthy males. Full article

Background and Objectives: Vein of Galen aneurysmal malformations (VGAMs) represent the most common vascular malformations of the brain at the pediatric age. Comprehension of its angioarchitecture and clinical features may influence their treatment options and functional outcomes. The aim of this review is to give an update of the anatomical and technical aspects of the management of VGAMs after endovascular treatment. Materials and Methods: We conducted a systematic review of original articles published between 1 January 2014 and 1 February 2024 in Pubmed, Web of Science (WOS), and Scopus databases following PRISMA guidelines. Variables such as age, sex, angioarchitecture of the malformation, clinical presentation, embolization technique, rate of occlusion, post-procedural complications, follow-up time, and mortality were collected. Random-effect meta-analysis of proportions was performed. Results: Fifteen studies on a total of 400 patients with VGAMs were collected. A total of 65.1% was male. The age at diagnosis was 12% prenatal, 35.5% neonates, 34.1% infants, 15.1% children, and 3.3% adults. Clinical presentation included 31.4% increased head size, 25.7% congestive heart failure, 12.9% neurological deficits, 10% seizures, 9.3% prominence of facial veins, and 8.9% developmental delay. A total of 339 patients underwent endovascular treatment (84.8%) with an average of 2.1 procedures per patient. The embolization technique was defined by transarterial access and glue material. Radiological occlusion was complete in 62.3% of the patients. The most frequent periprocedural incidents included hemorrhagic events (28.4%), embolization material migration (25.7%), and death (22%). The functional outcome was good in 68% of the surviving patients. The average follow-up time was 43.18 months. High heterogeneity was found in all outcomes but mortality rate. Conclusions: The angioarchitecture of VGAMs is significantly important when planning endovascular treatment and may have an influence on functional outcomes. More research into endovascular techniques and the risks of periprocedural complications must be performed. Indeed, a homogeneous protocol for the assessment of surviving VGAM patients during follow-up is necessary. Full article

Non-contact heart monitoring is crucial in advancing telemedicine, fitness tracking, and mass screening. Remote photoplethysmography (rPPG) is a non-contact technique to obtain information about heart pulse by analyzing the changes in the light intensity reflected or absorbed by the skin during the blood circulation cycle. However, this technique is sensitive to environmental lightning and different skin pigmentation, resulting in unreliable results. This research presents a multimodal approach to non-contact heart rate estimation by combining facial video and physical attributes, including age, gender, weight, height, and body mass index (BMI). For this purpose, we collected local datasets from 60 individuals containing a 1 min facial video and physical attributes such as age, gender, weight, and height, and we derived the BMI variable from the weight and height. We compare the performance of two machine learning models, support vector regression (SVR) and random forest regression on the multimodal dataset. The experimental results demonstrate that incorporating a multimodal approach enhances model performance, with the random forest model achieving superior results, yielding a mean absolute error (MAE) of 3.057 bpm, a root mean squared error (RMSE) of 10.532 bpm, and a mean absolute percentage error (MAPE) of 4.2% that outperforms the state-of-the-art rPPG methods. These findings highlight the potential for interpretable, non-contact, real-time heart rate measurement systems to contribute effectively to applications in telemedicine and mass screening. Full article

Cardiovascular diseases are a major cause of mortality worldwide. Long-term monitoring of nighttime heart rate (HR) and heart rate variability (HRV) may be useful in identifying latent cardiovascular risk. The Oura Ring has shown excellent correlation only with ECG-derived HR, but not HRV. We thus assessed if stringent data quality filters can improve the accuracy of time-domain and frequency-domain HRV measures. 92 younger (<45 years) and 22 older (≥45 years) participants from two in-lab sleep studies with concurrent overnight Oura and ECG data acquisition were analyzed. For each 5 min segment during time-in-bed, the validity proportion (percentage of interbeat intervals rated as valid) was calculated. We evaluated the accuracy of Oura-derived HR and HRV measures against ECG at different validity proportion thresholds: 80%, 50%, and 30%; and aggregated over different durations: 5 min, 30 min, and Night-level. Strong correlation and agreements were obtained for both age groups across all HR and HRV metrics and window sizes. More stringent validity proportion thresholds and averaging over longer time windows (i.e., 30 min and night) improved accuracy. Higher discrepancies were found for HRV measures, with more than half of older participants exceeding 10% Median Absolute Percentage Error. Accurate HRV measures can be obtained from Oura’s PPG-derived signals with a stringent validity proportion threshold of around 80% for each 5 min segment and aggregating over time windows of at least 30 min. Full article

Smart Rings (SRs) are user-friendly devices capable of measuring various health parameters, making them suitable for remote continuous monitoring in diverse clinical settings. Since the available evidence on the accuracy of SRs recording health data is highly heterogeneous, this systematic review, conducted in accordance with PRISMA guidelines, searched for articles evaluating the efficacy of SRs for sleep, respiratory, and cardiovascular monitoring across the PubMed, SCOPUS, and ProQuest databases. Meta-analyses were conducted for health outcomes evaluated in at least three studies with a comparable study population and design, and the same comparison device. Nineteen articles were included: eleven analyses focused on sleep quality, eight on cardiovascular parameters, and one on oxygen saturation. Studies analysing cardiovascular outcomes found a good accuracy of SRs in measuring heart rate (HR) with a mean bias of −0.4 bpms (limits of agreement (LoAs): −2.7; 1.8). The meta-analyses showed variability in SRs’ efficacy in monitoring total sleep time (mean bias: −21.3 min, LoAs: −69.9, 27.4) and REM duration (mean bias: −18.2 min, LoAs: −33.3, −3.1). The results highlighted the promising potential of SRs for HR monitoring. Further research is needed to clarify the reliability of SRs in monitoring sleep quality and their use directed to a broader range of health parameters. With further development, SRs could become valuable tools for healthcare professionals. Full article

Background: Postoperative cardiac rehabilitation (CR) programs are increasingly recommended by clinicians, but only a minority of patients who have undergone open heart surgery participate in such programs. Participation rates in postoperative CR, if anything, appear to be declining. This systematic review examines the effectiveness of post-operative CR and reveals possible participation barriers. Methods: A search of two scholarly databases for primary research papers published in the last decade examining the impact of post-operative CR was conducted and the resultant papers reviewed. Results: The 21 resulting studies revealed physiological functioning improvement and a reduction in mortality and readmission rates, while highlighting an enhancement in mental status. Some of the studies recognized the need for nutritional support and suggested that age, gender, access to CR centers, and socioeconomic variables impact participation in CR. Conclusions: Post-operative CR participation rates continue to decline despite increasing evidence of the value of the approach. Full article

Background: In safety-critical environments, human error is a leading cause of accidents, with the loss of situation awareness (SA) being a key contributing factor. Accurate SA assessment is essential for minimizing such risks and ensuring operational safety. Traditional SA measurement methods have limitations in dynamic real-world settings, while physiological signals, particularly EEG, offer a non-invasive, real-time alternative for continuous SA monitoring. However, the reliability of SA measurement based on physiological signals depends on the accuracy of SA labeling. Objective: This study aims to design an effective SA measurement paradigm specific to high-speed train driving, investigate more accurate physiological signal-based SA labeling methods, and explore the relationships between SA levels and key physiological metrics based on the developed framework. Methods: This study recruited 19 male high-speed train driver trainees and developed an SA measurement paradigm specific to high-speed train driving. A method combining subjective SA ratings and task performance was introduced to generate accurate SA labels. Results: The results of statistical analysis confirmed the effectiveness of this paradigm in inducing SA level changes, revealing significant relationships between SA levels and key physiological metrics, including eye movement patterns, ECG features (e.g., heart rate variability), and EEG power spectral density across theta, alpha, and beta bands. Conclusions: This study supports the use of multimodal physiological signals for SA assessment and provides a theoretical foundation for future applications of SA monitoring in railway operations, contributing to enhanced operational safety. Full article