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Heliyon Mar 2024This work analyzes hemodynamic phenomena within the aorta of two elderly patients and their impact on blood flow behavior, particularly affected by an endovascular...
This work analyzes hemodynamic phenomena within the aorta of two elderly patients and their impact on blood flow behavior, particularly affected by an endovascular prosthesis in one of them (Patient II). Computational Fluid Dynamics (CFD) was utilized for this study, involving measurements of velocity, pressure, and wall shear stress (WSS) at various time points during the third cardiac cycle, at specific positions within two cross sections of the thoracic aorta. The first cross-section (Cross-Section 1, CS1) is located before the initial fluid bifurcation, just before the right subclavian artery. The second cross-section (Cross-Section 2, CS2) is situated immediately after the left subclavian artery. The results reveal that, under regular aortic geometries, velocity and pressure magnitudes follow the principles of fluid dynamics, displaying variations. However, in Patient II, an endoprosthesis near the CS2 and the proximal border of the endoprosthesis significantly disrupts fluid behavior owing to the pulsatile flow. The cross-sectional areas of Patient I are smaller than those of Patient II, leading to higher flow magnitudes. Although in CS1 of Patient I, there is considerable variability in velocity magnitudes, they exhibit a more uniform and predictable transition. In contrast, CS2 of Patient II, where magnitude variation is also high, displays irregular fluid behavior due to the endoprosthesis presence. This cross-section coincides with the border of the fluid bifurcation. Additionally, the irregular geometry caused by endovascular aneurysm repair contributes to flow disruption as the endoprosthesis adjusts to the endothelium, reshaping itself to conform with the vessel wall. In this context, significant alterations in velocity values, pressure differentials fluctuating by up to 10%, and low wall shear stress indicate the pronounced influence of the endovascular prosthesis on blood flow behavior. These flow disturbances, when compounded by the heart rate, can potentially lead to changes in vascular anatomy and displacement, resulting in a disruption of the prosthesis-endothelium continuity and thereby causing clinical complications in the patient.
PubMed: 38434340
DOI: 10.1016/j.heliyon.2024.e26355 -
Communications Medicine Feb 2024Long-term monitoring of Electrocardiogram (ECG) recordings is crucial to diagnose arrhythmias. Clinicians can find it challenging to diagnose arrhythmias, and this is a...
BACKGROUND
Long-term monitoring of Electrocardiogram (ECG) recordings is crucial to diagnose arrhythmias. Clinicians can find it challenging to diagnose arrhythmias, and this is a particular issue in more remote and underdeveloped areas. The development of digital ECG and AI methods could assist clinicians who need to diagnose arrhythmias outside of the hospital setting.
METHODS
We constructed a large-scale Chinese ECG benchmark dataset using data from 272,753 patients collected from January 2017 to December 2021. The dataset contains ECG recordings from all common arrhythmias present in the Chinese population. Several experienced cardiologists from Shanghai First People's Hospital labeled the dataset. We then developed a deep learning-based multi-label interpretable diagnostic model from the ECG recordings. We utilized Accuracy, F1 score and AUC-ROC to compare the performance of our model with that of the cardiologists, as well as with six comparison models, using testing and hidden data sets.
RESULTS
The results show that our approach achieves an F1 score of 83.51%, an average AUC ROC score of 0.977, and 93.74% mean accuracy for 6 common arrhythmias. Results from the hidden dataset demonstrate the performance of our approach exceeds that of cardiologists. Our approach also highlights the diagnostic process.
CONCLUSIONS
Our diagnosis system has superior diagnostic performance over that of clinicians. It also has the potential to help clinicians rapidly identify abnormal regions on ECG recordings, thus improving efficiency and accuracy of clinical ECG diagnosis in China. This approach could therefore potentially improve the productivity of out-of-hospital ECG diagnosis and provides a promising prospect for telemedicine.
PubMed: 38418628
DOI: 10.1038/s43856-024-00464-4 -
European Journal of Cell Biology Jun 2024Desmin gene mutations cause myopathies and cardiomyopathies. Our previously characterised R349P desminopathy mice, which carry the ortholog of the common human desmin...
Desmin gene mutations cause myopathies and cardiomyopathies. Our previously characterised R349P desminopathy mice, which carry the ortholog of the common human desmin mutation R350P, showed marked alterations in mitochondrial morphology and function in muscle tissue. By isolating skeletal muscle myoblasts from offspring of R349P desminopathy and p53 knock-out mice, we established an immortalised cellular disease model. Heterozygous and homozygous R349P desmin knock-in and wild-type myoblasts could be well differentiated into multinucleated spontaneously contracting myotubes. The desminopathy myoblasts showed the characteristic disruption of the desmin cytoskeleton and desmin protein aggregation, and the desminopathy myotubes showed the characteristic myofibrillar irregularities. Long-term electrical pulse stimulation promoted myotube differentiation and markedly increased their spontaneous contraction rate. In both heterozygous and homozygous R349P desminopathy myotubes, this treatment restored a regular myofibrillar cross-striation pattern as seen in wild-type myotubes. High-resolution respirometry of mitochondria purified from myotubes by density gradient ultracentrifugation revealed normal oxidative phosphorylation capacity, but a significantly reduced proton leak in mitochondria from the homozygous R349P desmin knock-in cells. Consistent with a reduced proton flux across the inner mitochondrial membrane, our quantitative proteomic analysis of the purified mitochondria revealed significantly reduced levels of ADP/ATP translocases in the homozygous R349P desmin knock-in genotype. As this alteration was also detected in the soleus muscle of R349P desminopathy mice, which, in contrast to the mitochondria purified from cultured cells, showed a variety of other dysregulated mitochondrial proteins, we consider this finding to be an early step in the pathogenesis of secondary mitochondriopathy in desminopathy.
Topics: Animals; Desmin; Mice; Muscle Fibers, Skeletal; Gene Knock-In Techniques; Protons; Mitochondria; Muscular Dystrophies; Cardiomyopathies
PubMed: 38412640
DOI: 10.1016/j.ejcb.2024.151399 -
BioRxiv : the Preprint Server For... Feb 2024Regaining sensory feedback is pivotal for people living with limb amputation. Electrical stimulation of sensory fibers in peripheral nerves has been shown to restore...
Regaining sensory feedback is pivotal for people living with limb amputation. Electrical stimulation of sensory fibers in peripheral nerves has been shown to restore focal percepts in the missing limb. However, conventional rectangular current pulses induce sensations often described as unnatural. This is likely due to the synchronous and periodic nature of activity evoked by these pulses. Here we introduce a fast-oscillating amplitude-modulated sinusoidal (FAMS) stimulation waveform that desynchronizes evoked neural activity. We used a computational model to show that sinusoidal waveforms evoke asynchronous and irregular firing and that firing patterns are frequency dependent. We designed the FAMS waveform to leverage both low- and high-frequency effects and found that membrane non-linearities enhance neuron-specific differences when exposed to FAMS. We implemented this waveform in a feline model of peripheral nerve stimulation and demonstrated that FAMS-evoked activity is more asynchronous than activity evoked by rectangular pulses, while being easily controllable with simple stimulation parameters. These results represent an important step towards biomimetic stimulation strategies useful for clinical applications to restore sensory feedback.
PubMed: 38405798
DOI: 10.1101/2024.02.14.580219 -
American Heart Journal May 2024Atrial fibrillation (AF) increases the risk of death, stroke, heart failure, cognitive decline, and healthcare costs but is often asymptomatic and undiagnosed. There is... (Observational Study)
Observational Study
BACKGROUND
Atrial fibrillation (AF) increases the risk of death, stroke, heart failure, cognitive decline, and healthcare costs but is often asymptomatic and undiagnosed. There is currently no national screening program for AF. The advent of validated hand-held devices allows AF to be detected in non-healthcare settings, enabling screening to be undertaken within the community.
METHOD AND RESULTS
In this novel observational study, we embedded a MyDiagnostick single lead ECG sensor into the handles of shopping trolleys in four supermarkets in the Northwest of England: 2155 participants were recruited. Of these, 231 participants either activated the sensor or had an irregular pulse, suggesting AF. Some participants agreed to use the sensor but refused to provide their contact details, or consent to pulse assessment. In addition, some data were missing, resulting in 203 participants being included in the final analyses. Fifty-nine participants (mean age 73.6 years, 43% female) were confirmed or suspected of having AF; 20 were known to have AF and 39 were previously undiagnosed. There was no evidence of AF in 115 participants and the remaining 46 recordings were non-diagnostic, mainly due to artefact. Men and older participants were significantly more likely to have newly diagnosed AF. Due to the number of non-diagnostic ECGs (n = 46), we completed three levels of analyses, excluding all non-diagnostic ECGs, assuming all non-diagnostic ECGs were masking AF, and assuming all non-diagnostic ECGs were not AF. Based on the results of the three analyses, the sensor's sensitivity (95% CI) ranged from 0.70 to 0.93; specificity from 0.15 to 0.97; positive predictive values (PPV) and negative predictive values (NPV) ranged from 0.24 to 0.56 and 0.55 to 1.00, respectively. These values should be interpreted with caution, as the ideal reference standard on 1934 participants was imperfect.
CONCLUSION
The study demonstrates that the public will engage with AF screening undertaken as part of their daily routines using hand-held devices. Sensors can play a key role in identifying asymptomatic patients in this way, but the technology must be further developed to reduce the quantity of non-diagnostic ECGs.
Topics: Humans; Atrial Fibrillation; Male; Female; Feasibility Studies; Aged; Electrocardiography; Mass Screening; England; Middle Aged; Aged, 80 and over
PubMed: 38395294
DOI: 10.1016/j.ahj.2024.02.011 -
International Journal of Pediatrics 2024Respiratory difficulties are a common concern in preterm infants, and they can lead to long-term health problems. Few studies have investigated the use of spectral...
BACKGROUND
Respiratory difficulties are a common concern in preterm infants, and they can lead to long-term health problems. Few studies have investigated the use of spectral analysis as a biomarker to quantify respiration patterns in preterm infants.
OBJECTIVE
To evaluate the feasibility of using spectral analysis of heart rate variability as a biomarker for the quantification of respiratory patterns in very-low-birth-weight preterm infants compared to direct observation.
METHODS
In a comparative, small-scale feasibility study, 18 preterm infants born during their 27 to 28 gestational week (weighing <1500 grams) participated by convenience. Respiratory patterns (regular or irregular; shallow or deep) were directly observed on the 28 week during playback of speech recording. Heart rate variability was simultaneously measured using spectral analysis of heart periods, from which the mean values influenced by respiratory sinus arrhythmia (frequencies of 0.30-1.0 Hz) were compared to each observed respiratory pattern. The magnitudes of respiratory sinus arrhythmia and the area under the curve were determined.
RESULTS
The magnitude of respiratory sinus arrhythmia (frequencies of 0.30-1.0 Hz) in infants observed to be displaying irregular shallow respiration was greater than that in infants with regular deep respiration. Further, there was a shift from lower frequencies (frequency peak = 0.30 Hz) to higher frequencies (peak = 0.70 Hz).
CONCLUSION
In contrast with direct observation, spectral analysis allowed for the quantification of respiratory patterns in a vulnerable population of preterm infants of interest to the nursing scientific and practice community. Future directions include applying this biomarker to evaluate both developmental and pathological trends in the respiratory patterns of preterm infants.
PubMed: 38314331
DOI: 10.1155/2024/6671906 -
Therapeutic Advances in Drug Safety 2024Atrial fibrillation (AF) and obesity are common conditions globally; yet, there remains suboptimal pharmacological management contributing to high rates of...
BACKGROUND
Atrial fibrillation (AF) and obesity are common conditions globally; yet, there remains suboptimal pharmacological management contributing to high rates of hospitalization in patients with AF. The altered pathophysiology of both obese and underweight individuals may influence the pharmacology of medications, including those used to manage AF. This, in turn, increases the risk of adverse events and impacts patient risk for stroke and rehospitalization. Despite the well-established complications of obesity, research investigating the relationship between obesity and AF is scant.
OBJECTIVES
The primary aim of this study is to describe cardiovascular-related hospitalization in AF patients according to BMI categories. A secondary aim is to describe anticoagulant and antiarrhythmic prescribing practice patterns in patients with AF, according to the BMI category.
DESIGN
A retrospective, exploratory descriptive observational cohort study, using routinely collected electronic medical record data from five public hospitals within a single health district, with a population dominantly that is culturally and linguistically diverse, and has a low socioeconomic status.
METHODS AND ANALYSIS
Data extraction will include a 24-month period (January 2017 to December 2018) with a 12-month follow-up. All adult (⩾18 years) patients at discharge diagnosed with AF, prescribed any oral anticoagulant and/or oral rate/rhythm control agent, will be eligible for inclusion.
ETHICS AND DISSEMINATION
Ethics approval from the health district and the University of Wollongong has been granted. Findings will seek to demonstrate associations between management strategies and patient outcomes, as well as describe patterns of acute care management from prescribers. These data will be used to inform and generate hypotheses for large-scale studies examining the impact of body weight on anticoagulation prescribing at national and global scales.
PubMed: 38300763
DOI: 10.1177/20420986241227014 -
PLOS Digital Health Jan 2024The interplay between circadian rhythms, time awake, and mood remains poorly understood in the real-world. Individuals in high-stress occupations with irregular...
The interplay between circadian rhythms, time awake, and mood remains poorly understood in the real-world. Individuals in high-stress occupations with irregular schedules or nighttime shifts are particularly vulnerable to depression and other mood disorders. Advances in wearable technology have provided the opportunity to study these interactions outside of a controlled laboratory environment. Here, we examine the effects of circadian rhythms and time awake on mood in first-year physicians using wearables. Continuous heart rate, step count, sleep data, and daily mood scores were collected from 2,602 medical interns across 168,311 days of Fitbit data. Circadian time and time awake were extracted from minute-by-minute wearable heart rate and motion measurements. Linear mixed modeling determined the relationship between mood, circadian rhythm, and time awake. In this cohort, mood was modulated by circadian timekeeping (p<0.001). Furthermore, we show that increasing time awake both deteriorates mood (p<0.001) and amplifies mood's circadian rhythm nonlinearly. These findings demonstrate the contributions of both circadian rhythms and sleep deprivation to underlying mood and show how these factors can be studied in real-world settings using Fitbits. They underscore the promising opportunity to harness wearables in deploying chronotherapies for psychiatric illness.
PubMed: 38295082
DOI: 10.1371/journal.pdig.0000439 -
Alternative Therapies in Health and... Jan 2024In China, there have been instances of sudden cardiac death among university students, with a significant number of students being at risk of cardiovascular diseases....
BACKGROUND
In China, there have been instances of sudden cardiac death among university students, with a significant number of students being at risk of cardiovascular diseases. This risk is often attributed to sub-health conditions such as weight gain and obesity, which are triggered by sedentary lifestyles, irregular living habits, and unregulated diets. Therefore, it is crucial to enhance the guidance for participation in physical activities, encouraging students to actively reduce their risk of cardiovascular diseases (CVD). Jogging, characterized by its convenience, simplicity, and low-risk participation, has been widely accepted by university students. This study takes the impact of jogging on the cardiovascular function of university students as a starting point. It aims to explore the content of the changing process suitable for the development of cardiovascular function in university students. The ultimate goal is to promote the healthy development of the cardiovascular system function in university students and improve their adherence to physical activities.
METHODS
The study recruited 60 university students with no exercise habits through on-campus poster advertisements. These 60 participants were randomly divided into two groups. The students in the experimental group were required to jog no less than three times a week, with each session lasting at least 30 minutes. The organizers of the experiment would remind the students daily in a WeChat group to complete their weekly exercise plan and persist in jogging, promoting the benefits of this activity. During jogging, the students used the Keep mobile application to record their jogging time and heart rate, which they then uploaded to the WeChat group. Follow-ups were conducted with students who did not complete their exercise plan, providing encouragement and guidance to continue participating in the experiment. The study employed a comparative research approach between the experimental group and the control group.
RESULTS
According to the experimental protocol, after 12 weeks of jogging intervention, the cardiovascular health indicators of both male and female students in the experimental group showed positive changes. Measurements of cardiac function indicators in the experimental group of boys SPTI, DPTI, ED has decreased, SEVR has increased, the relevant indicators compared with the relevant indicators of the control group (P < .05) is significant; in the experimental group of girls, SPTI, DPTI, SEVR indicators decreased, ED increased, and compared with the relevant indicators of the control group (P < .01) has a very significant significance. Changes in vascular indicators in the experimental and control groups after the experiment, SBP, DBP, PP, CAP decreased in the experimental group, and DBP, CAP in the male and female groups were found to be (P < .01), with highly significant changes; while SBP, PP intergroup comparison (P < .05), with significant changes.
CONCLUSION
Jogging is a good aerobic exercise program characterized by convenient ways of carrying out simple methods and low risk of participation. The benefits of jogging are not only reflected physiologically but also psychologically; it can make participants enhance their self-confidence and make their moods more pleasant. It can also improve sleep quality and maintain a good mental state. Long-term jogging habits can effectively improve endothelial function and heart contraction function, reduce blood pressure effectively prevent atherosclerosis and prevent CVD by reducing the incidence of CVD risk factors.
PubMed: 38290441
DOI: No ID Found -
Frontiers in Physiology 2023In atrial fibrillation (AF), the ECG P-wave, which represents atrial depolarization, is replaced with chaotic and irregular fibrillation waves (f waves). The f-wave...
In atrial fibrillation (AF), the ECG P-wave, which represents atrial depolarization, is replaced with chaotic and irregular fibrillation waves (f waves). The f-wave frequency, , shows significant variations over time. Cardiorespiratory interactions regulated by the autonomic nervous system have been suggested to play a role in such variations. We conducted a simulation study to test whether the spatiotemporal release pattern of the parasympathetic neurotransmitter acetylcholine (ACh) modulates the frequency of atrial reentrant circuits. Understanding parasympathetic involvement in AF may guide more effective treatment approaches and could help to design autonomic markers alternative to heart rate variability (HRV), which is not available in AF patients. 2D tissue and 3D whole-atria models of human atrial electrophysiology in persistent AF were built. Different ACh release percentages (8% and 30%) and spatial ACh release patterns, including spatially random release and release from ganglionated plexi (GPs) and associated nerves, were considered. The temporal pattern of ACh release, ACh(), was simulated following a sinusoidal waveform of frequency 0.125 Hz to represent the respiratory frequency. Different mean concentrations and peak-to-peak ranges of ACh (ΔACh) were tested. We found that temporal variations in , (), followed the simulated temporal ACh() pattern in all cases. The temporal mean of (), , depended on the fibrillatory pattern (number and location of rotors), the percentage of ACh release nodes and . The magnitude of () modulation, Δ , depended on the percentage of ACh release nodes and ΔACh. The spatial pattern of ACh release did not have an impact on and only a mild impact on Δ . The f-wave frequency, being indicative of vagal activity, has the potential to drive autonomic-based therapeutic actions and could replace HRV markers not quantifiable from AF patients.
PubMed: 38235381
DOI: 10.3389/fphys.2023.1189464