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Nature Oct 2023A regular heartbeat is essential to vertebrate life. In the mature heart, this function is driven by an anatomically localized pacemaker. By contrast, pacemaking...
A regular heartbeat is essential to vertebrate life. In the mature heart, this function is driven by an anatomically localized pacemaker. By contrast, pacemaking capability is broadly distributed in the early embryonic heart, raising the question of how tissue-scale activity is first established and then maintained during embryonic development. The initial transition of the heart from silent to beating has never been characterized at the timescale of individual electrical events, and the structure in space and time of the early heartbeats remains poorly understood. Using all-optical electrophysiology, we captured the very first heartbeat of a zebrafish and analysed the development of cardiac excitability and conduction around this singular event. The first few beats appeared suddenly, had irregular interbeat intervals, propagated coherently across the primordial heart and emanated from loci that varied between animals and over time. The bioelectrical dynamics were well described by a noisy saddle-node on invariant circle bifurcation with action potential upstroke driven by Ca1.2. Our work shows how gradual and largely asynchronous development of single-cell bioelectrical properties produces a stereotyped and robust tissue-scale transition from quiescence to coordinated beating.
Topics: Animals; Action Potentials; Embryonic Development; Heart; Heart Rate; Zebrafish; Electrophysiology; Single-Cell Analysis
PubMed: 37758945
DOI: 10.1038/s41586-023-06561-z -
The Cochrane Database of Systematic... Jun 2016Atrial fibrillation (AF), the most common arrhythmia in clinical practice, is a leading cause of morbidity and mortality. Screening for AF in asymptomatic patients has... (Review)
Review
BACKGROUND
Atrial fibrillation (AF), the most common arrhythmia in clinical practice, is a leading cause of morbidity and mortality. Screening for AF in asymptomatic patients has been proposed as a way of reducing the burden of the disease by detecting people who would benefit from prophylactic anticoagulation therapy before the onset of symptoms. However, for screening to be an effective intervention, it must improve the detection of AF and provide benefit for those detected earlier as a result of screening.
OBJECTIVES
This review aims to answer the following questions.Does systematic screening increase the detection of AF compared with routine practice? Which combination of screening population, strategy and test is most effective for detecting AF compared with routine practice? What safety issues and adverse events may be associated with individual screening programmes? How acceptable is the intervention to the target population? What costs are associated with systematic screening for AF?
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid) and EMBASE (Ovid) up to 11 November 2015. We searched other relevant research databases, trials registries and websites up to December 2015. We also searched reference lists of identified studies for potentially relevant studies, and we contacted corresponding authors for information about additional published or unpublished studies that may be relevant. We applied no language restrictions.
SELECTION CRITERIA
Randomised controlled trials comparing screening for AF with routine practice in people 40 years of age and older were eligible. Two review authors (PM and CT) independently selected trials for inclusion.
DATA COLLECTION AND ANALYSIS
Two review authors (PM and CT) independently assessed risk of bias and extracted data. We used odds ratios (ORs) and 95% confidence intervals (CIs) to present results for the primary outcome, which is a dichotomous variable. As we identified only one study for inclusion, we performed no meta-analysis. We used the GRADE (Grades of Recommendation, Assessment, Development and Evaluation Working Group) method to assess the quality of the evidence and GRADEPro to create a 'Summary of findings' table.
MAIN RESULTS
One cluster-randomised controlled trial met the inclusion criteria for this review. This study compared systematic screening (by invitation to have an electrocardiogram (ECG)) and opportunistic screening (pulse palpation during a general practitioner (GP) consultation for any reason, followed by an ECG if pulse was irregular) versus routine practice (normal case finding on the basis of clinical presentation) in people 65 years of age or older.Results show that both systematic screening and opportunistic screening of people over 65 years of age are more effective than routine practice (OR 1.57, 95% CI 1.08 to 2.26; and OR 1.58, 95% CI 1.10 to 2.29, respectively; both moderate-quality evidence). We found no difference in the effectiveness of systematic screening and opportunistic screening (OR 0.99, 95% CI 0.72 to 1.37; low-quality evidence). A subgroup analysis found that systematic screening and opportunistic screening were more effective in men (OR 2.68, 95% CI 1.51 to 4.76; and OR 2.33, 95% CI 1.29 to 4.19, respectively) than in women (OR 0.98, 95% CI 0.59 to 1.62; and OR 1.2, 95% CI 0.74 to 1.93, respectively). No adverse events associated with screening were reported.The incremental cost per additional case detected by opportunistic screening was GBP 337, compared with GBP 1514 for systematic screening. All cost estimates were based on data from the single included trial, which was conducted in the UK between 2001 and 2003.
AUTHORS' CONCLUSIONS
Evidence suggests that systematic screening and opportunistic screening for AF increase the rate of detection of new cases compared with routine practice. Although these approaches have comparable effects on the overall AF diagnosis rate, the cost of systematic screening is significantly greater than the cost of opportunistic screening from the perspective of the health service provider. Few studies have investigated effects of screening in other health systems and in younger age groups; therefore, caution needs to be exercised in relation to transferability of these results beyond the setting and population in which the included study was conducted.Additional research is needed to examine the effectiveness of alternative screening strategies and to investigate the effects of the intervention on risk of stroke for screened versus non-screened populations.
Topics: Aged; Asymptomatic Diseases; Atrial Fibrillation; Electrocardiography; Female; Humans; Male; Mass Screening; Palpation; Pulse; Randomized Controlled Trials as Topic
PubMed: 27258214
DOI: 10.1002/14651858.CD009586.pub3 -
Journal of UOEH Dec 1997Several findings of the author's own mental workload research are reviewed. Especially, factors, except task demand, influencing mental workload indexes are discussed.... (Review)
Review
Several findings of the author's own mental workload research are reviewed. Especially, factors, except task demand, influencing mental workload indexes are discussed. First, an experiment using the National Aeronautics and Space Administration Task Load Index (NASA TLX) is reviewed and the effects of a prior task load on a subsequent subjective workload are described. In a physiological measures section, the low reliability of the heart rate variability (HRV) parameters when the subjects' respiration pattern are highly irregular, and the existence of low sweat respondent, although perspiration seems to be sensitive to the workload, are indicated. Furthermore, results of the task specific physiological responses and of a HRV parameter affected by the individual characteristics, like type A behavior pattern, are shown. Discrepancy between autonomic nervous system activity measures may be solvable by introducing a new concept of autonomic space (synergism of sympathetic and parasympathetic nervous system). Finally, the need for strategies of data management concerning the individual differences is emphasized.
Topics: Autonomic Nervous System; Heart Rate; Humans; Individuality; Respiration; Stress, Psychological; Sweating; Workload
PubMed: 9431583
DOI: 10.7888/juoeh.19.313 -
Transfusion Medicine (Oxford, England) Feb 2012During apheresis, donors have up to 6 · 5 L of blood processed and receive citrated plasma during the return cycle. It is of concern that a donor with an unrecognised... (Clinical Trial)
Clinical Trial
OBJECTIVES
During apheresis, donors have up to 6 · 5 L of blood processed and receive citrated plasma during the return cycle. It is of concern that a donor with an unrecognised significant cardiac abnormality might therefore be put at further risk during apheresis.
BACKGROUND
Apheresis donors with cardiac abnormalities may be at increased risk of severe adverse reactions as a result of repeated volume loss or the adverse effect of citrate anticoagulant on cardiac contractility as the result of reduction in ionised calcium. An abnormal rate or rhythm may indicate a cardiac abnormality.
METHODS
At two donation centres between May 2001 and April 2009, the pulse rate and rhythm of every donor was measured before each apheresis procedure they underwent. Donors with a pulse rate outside the range 50-100 beats per minute and/or pulse irregularity were deferred from donation and referred to their general practitioner (GP).
RESULTS
Data from 3945 apheresis donors (3874 platelet donors, 71 plasma donors, 3595 males, 350 females) were reviewed. Two hundred thirty-eight donors (6%) were identified as having abnormal pulses and were referred to their GP. Eighty-one donors had bradycardia, 16 had tachycardia and 141 had an irregular pulse. Fifteen of the 3945 donors (0 · 4%) were found to have significant cardiac disease and withdrawn from the donor panel.
CONCLUSIONS
By simple monitoring, donors who may be at increased risk from the apheresis procedure can be identified. By performing pre-donation pulse assessment of all apheresis donors, we fulfil our medicolegal duty by not putting donors at avoidable risk.
Topics: Blood Component Removal; Blood Donors; Donor Selection; Female; Heart Diseases; Heart Rate; Humans; Male
PubMed: 22132749
DOI: 10.1111/j.1365-3148.2011.01119.x -
Vox Sanguinis May 2013In many jurisdictions, blood donors who have an atypical pulse rate are temporarily deferred. This practice is not supported by evidence. We evaluated whether accepting...
BACKGROUND AND OBJECTIVES
In many jurisdictions, blood donors who have an atypical pulse rate are temporarily deferred. This practice is not supported by evidence. We evaluated whether accepting donors with an atypical pulse rate increases their risk of cardiac ischaemic events.
METHODS
We measured the cumulative incidence of hospitalizations and deaths for coronary heart disease within 1 year of follow-up among donors who, between 2002 and 2006, were temporarily deferred because of an atypical pulse (<50 beats/min, >100 beats/min, or irregular). We compared this incidence to that observed among donors who also had an atypical pulse but who were allowed to donate, following a change in our deferral policy in 2007. The occurrence of cardiac events was determined through hospital discharge and death registries.
RESULTS
Among 6076 donors who were temporarily deferred for an atypical pulse, the 1-year rate of hospitalization or death for cardiac ischaemic events was 3.5/1000, compared to 2.4 in donors who had an atypical pulse but who were allowed to donate (n =10,671), for an adjusted odds ratio of 1.7 (95% CI, 0.9-3.0, P=0.08).
CONCLUSION
Regardless of the clinical significance of an atypical pulse rate, our data show that accepting donors with this condition does not increase the occurrence of serious cardiac ischaemic events. We conclude that pulse rate measurement in prospective donors is not warranted.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blood Donors; Coronary Disease; Female; Heart Rate; Humans; Incidence; Male; Middle Aged; Myocardial Ischemia; Quebec; Risk Factors; Young Adult
PubMed: 23134533
DOI: 10.1111/vox.12002 -
Sensors (Basel, Switzerland) Nov 2021Heart rate (HR) is an essential indicator of health in the human body. It measures the number of times per minute that the heart contracts or beats. An irregular...
Heart rate (HR) is an essential indicator of health in the human body. It measures the number of times per minute that the heart contracts or beats. An irregular heartbeat can signify a severe health condition, so monitoring heart rate periodically can help prevent heart complications. This paper presents a novel wearable sensing approach for remote HR measurement by a compact resistance-to-microcontroller interface circuit. A heartbeat's signal can be detected by a Force Sensing Resistor (FSR) attached to the body near large arteries (such as the carotid or radial), which expand their area each time the heart expels blood to the body. Depending on how the sensor interfaces with the subject, the FSR changes its electrical resistance every time a pulse is detected. By placing the FSR in a direct interface circuit, those resistance variations can be measured directly by a microcontroller without using either analog processing stages or an analog-to-digital converter. In this kind of interface, the self-heating of the sensor is avoided, since the FSR does not require any voltage or bias current. The proposed system has a sampling rate of 50 Sa/s, and an effective resolution of 10 bits (200 mΩ), enough for obtaining well-shaped cardiac signals and heart rate estimations in real time by the microcontroller. With this approach, the implementation of wearable systems in health monitoring applications is more feasible.
Topics: Electric Impedance; Heart Rate; Humans; Monitoring, Physiologic; Palpation; Wearable Electronic Devices
PubMed: 34833626
DOI: 10.3390/s21227549 -
Ceska a Slovenska Farmacie : Casopis... 2019The aim of the study was to raise the awareness of atrial fibrillation (AF) and the importance of pulse check in Czech pharmacies as well as to point out further...
OBJECTIVE
The aim of the study was to raise the awareness of atrial fibrillation (AF) and the importance of pulse check in Czech pharmacies as well as to point out further possibilities of developing consulting activities in pharmacies.
METHOD
Our project was performed as part of a worldwide campaign during three weeks: Heart Rhythm Week (06/2017) and Atrial Fibrillation Awareness Week (11/2017, 11/2018). Pharmacies actively providing indi-vidual counselling offered manual pulse check to patients aged 40 years without chronic anticoagulant therapy. Whenever high risk of AF was observed, patients were referred to a physician for further evaluation.
RESULTS
Pharmacists undertook pulse checks in 187 patients (mean age 59.0 ± 12.3 years; 70.6% women) in 14 participating pharmacies. The most common symptoms were fatigue (42.2%) and palpitations (20.9%), however, 40.6% of patients were asymptomatic. The mean heart rate was 73.2 ± 11.3 beats per minute (min. 51; max. 135) and irregular pulse was observed in 4.3% patients. The average CHA2DS2-VASc score was 2.0 ± 1.3. Eight (4.3%) patients were referred to a physician and in 5 patients (2.7%) the arrhythmia was diagnosed.
CONCLUSION
Czech pharmacies have successfully adopted this campaign, are interested in continuity of the project and may thus contribute to raise awareness of AF.
Topics: Adult; Aged; Anticoagulants; Atrial Fibrillation; Czech Republic; Female; Heart Rate; Humans; Male; Middle Aged; Pharmaceutical Services; Pharmacies; Pilot Projects
PubMed: 31896263
DOI: No ID Found -
Physical and Engineering Sciences in... Dec 2021Electrocardiogram (ECG) and photoplethysmograph (PPG) are non-invasive techniques that provide electrical and hemodynamic information of the heart, respectively. This... (Review)
Review
Electrocardiogram (ECG) and photoplethysmograph (PPG) are non-invasive techniques that provide electrical and hemodynamic information of the heart, respectively. This information is advantageous in the diagnosis of various cardiac abnormalities. Arrhythmia is the most common cardiovascular disease, manifested as single or multiple irregular heartbeats. However, due to the continuous manual observation, it becomes troublesome for experts sometimes to identify the paroxysmal nature of arrhythmia correctly. Moreover, due to advancements in technology, there is an inclination towards wearable sensors which monitor such patients continuously. Thus, there is a need for automatic detection techniques for the identification of arrhythmia. In the presented work, ECG and PPG-based state-of-the-art methods have been described, including preprocessing, feature extraction, and classification techniques for the detection of various arrhythmias. Additionally, this review exhibits various wearable sensors used in the literature and public databases available for the evaluation of results. The study also highlights the limitations of the current techniques and pragmatic solutions to improvise the ongoing effort.
Topics: Arrhythmias, Cardiac; Databases, Factual; Electrocardiography; Heart Rate; Humans; Photoplethysmography
PubMed: 34727361
DOI: 10.1007/s13246-021-01072-5 -
Heart Rhythm Oct 2016
Topics: Diagnosis, Differential; Electrocardiography; Heart Conduction System; Heart Rate; Humans; Male; Ventricular Premature Complexes; Young Adult
PubMed: 27659256
DOI: 10.1016/j.hrthm.2015.10.026 -
International Journal of Sports Medicine Jun 2009Over the past 25 years sport climbing has developed from an elite extreme sport subculture pursued by few into a mainstream recreational sport enjoyed globally by... (Review)
Review
Over the past 25 years sport climbing has developed from an elite extreme sport subculture pursued by few into a mainstream recreational sport enjoyed globally by climbers of all ages, climbing abilities, and with pre-existing health conditions. As the demands and grades of climbing difficulty have increased over this period, most scientific literature on sport climbing focused on acute injuries and overuse syndromes, or performance physiology in healthy adult males. The physiological response to sport climbing is more similar to that of resistance training (i.e., body building) rather than a predominantly aerobic sport (i.e., running, cycling), so that heart rate and blood pressure during a climb will be disproportionately high relative to the 'exercise' of climbing, and breathing may be irregular. Therefore this review sought evidence-based recommendations for recreational sport climbing participation by those individuals with pre-existing cardiopulmonary medical conditions including coronary heart disease, chronic heart failure, cardiac dysrhythmia, pulmonary diseases (i.e., asthma) or hypertension. This review defines the criteria that must be fulfilled for safe sport climbing by those with pre-existing cardiopulmonary conditions or those with hypertension.
Topics: Adult; Blood Pressure; Cardiovascular Diseases; Evidence-Based Medicine; Heart Rate; Humans; Lung Diseases; Male; Mountaineering
PubMed: 19199210
DOI: 10.1055/s-0028-1112143