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Neuroscience Apr 2021Perceiving the temporal regularity in a sequence of repetitive sensory events facilitates the preparation and execution of relevant behaviors with tight temporal...
Perceiving the temporal regularity in a sequence of repetitive sensory events facilitates the preparation and execution of relevant behaviors with tight temporal constraints. How we estimate temporal regularity from repeating patterns of sensory stimuli is not completely understood. We developed a decision-making task in which participants had to decide whether a train of visual, auditory, or tactile pulses, had a regular or an irregular temporal pattern. We tested the hypothesis that subjects categorize stimuli as irregular by accumulating the time differences between the predicted and observed times of sensory pulses defining a temporal rhythm. Results suggest that instead of waiting for a single large temporal deviation, participants accumulate timing-error signals and judge a pattern as irregular when the amount of evidence reaches a decision threshold. Model fits of bounded integration showed that this accumulation occurs with negligible leak of evidence. Consistent with previous findings, we show that participants perform better when evaluating the regularity of auditory pulses, as compared with visual or tactile stimuli. Our results suggest that temporal regularity is estimated by comparing expected and measured pulse onset times, and that each prediction error is accumulated towards a threshold to generate a behavioral choice.
Topics: Auditory Perception; Humans; Touch
PubMed: 33549694
DOI: 10.1016/j.neuroscience.2021.01.035 -
Computational Intelligence and... 2022One of the most challenging tasks for clinicians is detecting symptoms of cardiovascular disease as earlier as possible. Many individuals worldwide die each year from...
One of the most challenging tasks for clinicians is detecting symptoms of cardiovascular disease as earlier as possible. Many individuals worldwide die each year from cardiovascular disease. Since heart disease is a major concern, it must be dealt with timely. Multiple variables affecting health, such as excessive blood pressure, elevated cholesterol, an irregular pulse rate, and many more, make it challenging to diagnose cardiac disease. Thus, artificial intelligence can be useful in identifying and treating diseases early on. This paper proposes an ensemble-based approach that uses machine learning (ML) and deep learning (DL) models to predict a person's likelihood of developing cardiovascular disease. We employ six classification algorithms to predict cardiovascular disease. Models are trained using a publicly available dataset of cardiovascular disease cases. We use random forest (RF) to extract important cardiovascular disease features. The experiment results demonstrate that the ML ensemble model achieves the best disease prediction accuracy of 88.70%.
Topics: Algorithms; Artificial Intelligence; Cardiovascular Diseases; Heart Diseases; Humans; Machine Learning
PubMed: 36017452
DOI: 10.1155/2022/5267498 -
Cardiovascular Research Jun 2021Modern cardiac electrophysiology has reported significant advances in the understanding of mechanisms underlying complex wave propagation patterns during atrial... (Review)
Review
Modern cardiac electrophysiology has reported significant advances in the understanding of mechanisms underlying complex wave propagation patterns during atrial fibrillation (AF), although disagreements remain. One school of thought adheres to the long-held postulate that AF is the result of randomly propagating wavelets that wonder throughout the atria. Another school supports the notion that AF is deterministic in that it depends on a small number of high-frequency rotors generating three-dimensional scroll waves that propagate throughout the atria. The spiralling waves are thought to interact with anatomic and functional obstacles, leading to fragmentation and new wavelet formation associated with the irregular activation patterns documented on AF tracings. The deterministic hypothesis is consistent with demonstrable hierarchical gradients of activation frequency and AF termination on ablation at specific (non-random) atrial regions. During the last decade, data from realistic animal models and pilot clinical series have triggered a new era of novel methodologies to identify and ablate AF drivers outside the pulmonary veins. New generation electroanatomical mapping systems and multielectrode mapping catheters, complimented by powerful mathematical analyses, have generated the necessary platforms and tools for moving these approaches into clinical procedures. Recent clinical data using such platforms have provided encouraging evidence supporting the feasibility of targeting and effectively ablating driver regions in addition to pulmonary vein isolation in persistent AF. Here, we review state-of-the-art technologies and provide a comprehensive historical perspective, characterization, classification, and expected outcomes of current mechanism-based methods for AF ablation. We discuss also the challenges and expected future directions that scientists and clinicians will face in their efforts to understand AF dynamics and successfully implement any novel method into regular clinical practice.
Topics: Action Potentials; Animals; Atrial Fibrillation; Catheter Ablation; Heart Atria; Heart Rate; Humans; Recurrence; Treatment Outcome
PubMed: 33744913
DOI: 10.1093/cvr/cvab108 -
Frontiers in Bioscience (Scholar... Nov 2022Atrial fibrillation (AF) is a condition in which the electrical signals in the upper heart chambers (atria) are rapid and disorganized, producing an irregular and... (Review)
Review
Atrial fibrillation (AF) is a condition in which the electrical signals in the upper heart chambers (atria) are rapid and disorganized, producing an irregular and chaotical heartbeat. The sinus rhythm should be between 60 to 100 bpm at rest, while the heart rhythm in AF patients may be over 140 bpm. Either structural and electro-mechanical remodeling of the atrial tissue underlies the perpetuation and evolution of AF from the paroxysmal to persistent form. Unravelling the different pathological pathways involved in AF that lead to arrhythmogenesis and atrial remodeling is needed to discovery new and effective therapeutic approaches. A variety of drugs are available to convert and maintain the AF patient in a normal sinus rhythm; however, these strategies have limited chances of success or fail with the progression of AF to more persistent/permanent forms. Consequently, it is necessary to find new therapeutic targets for the relief of persistent or chronic AF forms, as well as the development of new and more effective pharmacological tools. The atrial specific two-pore domain K+ channels (K2P) constitute the background K+ current on atrial cardiomyocytes and modulate cell excitability emerging as novel targets in this disease and avoiding ventricle side effects. Moreover, several antiarrhythmic drugs used in AF treatment exert their mechanism of action in part by modulation of K2P channels. Thus far, TWIK-1, TREK-1, TASK-1, TASK-2 and TASK-3 channel have been identified as responsible for background currents IK2P current in atrial cells; however, it is not excluded that other K2PX subunits or subfamilies have physiological roles in atria. To date, a great diversity openers, activators and blockers of K2P channel have been identified, particularly those targeting TASK and TREK channels. Several studies have demonstrated that the expression of TWIK-1, TREK-1, TASK-1, TASK-2 and TASK-3 are dysregulated in AF and their pharmacology rescue could suppose a novel therapy in AF. The main objective is to examine the regulation of K2P channels and the current K2P channels pharmacological modulators for AF treatment.
Topics: Humans; Atrial Fibrillation; Heart Atria; Anti-Arrhythmia Agents; Heart Rate; Myocytes, Cardiac
PubMed: 36575841
DOI: 10.31083/j.fbs1404031 -
Health Technology Assessment... Jan 2020Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and is associated with an increased risk of stroke and congestive heart failure. Lead-I...
BACKGROUND
Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and is associated with an increased risk of stroke and congestive heart failure. Lead-I electrocardiogram (ECG) devices are handheld instruments that can be used to detect AF at a single time point in people who present with relevant signs or symptoms.
OBJECTIVE
To assess the diagnostic test accuracy, clinical impact and cost-effectiveness of using single time point lead-I ECG devices for the detection of AF in people presenting to primary care with relevant signs or symptoms, and who have an irregular pulse compared with using manual pulse palpation (MPP) followed by a 12-lead ECG in primary or secondary care.
DATA SOURCES
MEDLINE, MEDLINE Epub Ahead of Print and MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, PubMed, Cochrane Databases of Systematic Reviews, Cochrane Central Database of Controlled Trials, Database of Abstracts of Reviews of Effects and the Health Technology Assessment Database.
METHODS
The systematic review methods followed published guidance. Two reviewers screened the search results (database inception to April 2018), extracted data and assessed the quality of the included studies. Summary estimates of diagnostic accuracy were calculated using bivariate models. An economic model consisting of a decision tree and two cohort Markov models was developed to evaluate the cost-effectiveness of lead-I ECG devices.
RESULTS
No studies were identified that evaluated the use of lead-I ECG devices for patients with signs or symptoms of AF. Therefore, the diagnostic accuracy and clinical impact results presented are derived from an asymptomatic population (used as a proxy for people with signs or symptoms of AF). The summary sensitivity of lead-I ECG devices was 93.9% [95% confidence interval (CI) 86.2% to 97.4%] and summary specificity was 96.5% (95% CI 90.4% to 98.8%). One study reported limited clinical outcome data. Acceptability of lead-I ECG devices was reported in four studies, with generally positive views. The de novo economic model yielded incremental cost-effectiveness ratios (ICERs) per quality-adjusted life-year (QALY) gained. The results of the pairwise analysis show that all lead-I ECG devices generated ICERs per QALY gained below the £20,000-30,000 threshold. Kardia Mobile (AliveCor Ltd, Mountain View, CA, USA) is the most cost-effective option in a full incremental analysis.
LIMITATIONS
No published data evaluating the diagnostic accuracy, clinical impact or cost-effectiveness of lead-I ECG devices for the population of interest are available.
CONCLUSIONS
Single time point lead-I ECG devices for the detection of AF in people with signs or symptoms of AF and an irregular pulse appear to be a cost-effective use of NHS resources compared with MPP followed by a 12-lead ECG in primary or secondary care, given the assumptions used in the base-case model.
FUTURE WORK
Studies assessing how the use of lead-I ECG devices in this population affects the number of people diagnosed with AF when compared with current practice would be useful.
STUDY REGISTRATION
This study is registered as PROSPERO CRD42018090375.
FUNDING
The National Institute for Health Research Health Technology Assessment programme.
Topics: Atrial Fibrillation; Cost-Benefit Analysis; Electrocardiography; Heart Failure; Humans; Mass Screening; Models, Economic; Predictive Value of Tests; Primary Health Care; Pulse; Quality-Adjusted Life Years; Stroke; Technology Assessment, Biomedical
PubMed: 31933471
DOI: 10.3310/hta24030 -
European Journal of Preventive... Aug 2016Pulse palpation has been recommended as the first step of screening to detect atrial fibrillation. We aimed to determine and compare the accuracy of different methods... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Pulse palpation has been recommended as the first step of screening to detect atrial fibrillation. We aimed to determine and compare the accuracy of different methods for detecting pulse irregularities caused by atrial fibrillation.
METHODS
We systematically searched MEDLINE, EMBASE, CINAHL and LILACS until 16 March 2015. Two reviewers identified eligible studies, extracted data and appraised quality using the QUADAS-2 instrument. Meta-analysis, using the bivariate hierarchical random effects method, determined average operating points for sensitivities, specificities, positive and negative likelihood ratios (PLR, NLR); we constructed summary receiver operating characteristic plots.
RESULTS
Twenty-one studies investigated 39 interventions (n = 15,129 pulse assessments) for detecting atrial fibrillation. Compared to 12-lead electrocardiography (ECG) diagnosed atrial fibrillation, blood pressure monitors (BPMs; seven interventions) and non-12-lead ECGs (20 interventions) had the greatest accuracy for detecting pulse irregularities attributable to atrial fibrillation (BPM: sensitivity 0.98 (95% confidence interval (CI) 0.92-1.00), specificity 0.92 (95% CI 0.88-0.95), PLR 12.1 (95% CI 8.2-17.8) and NLR 0.02 (95% CI 0.00-0.09); non-12-lead ECG: sensitivity 0.91 (95% CI 0.86-0.94), specificity 0.95 (95% CI 0.92-0.97), PLR 20.1 (95% CI 12-33.7), NLR 0.09 (95% CI 0.06-0.14)). There were similar findings for smartphone applications (six interventions) although these studies were small in size. The sensitivity and specificity of pulse palpation (six interventions) were 0.92 (95% CI 0.85-0.96) and 0.82 (95% CI 0.76-0.88), respectively (PLR 5.2 (95% CI 3.8-7.2), NLR 0.1 (95% CI 0.05-0.18)).
CONCLUSIONS
BPMs and non-12-lead ECG were most accurate for detecting pulse irregularities caused by atrial fibrillation; other technologies may therefore be pragmatic alternatives to pulse palpation for the first step of atrial fibrillation screening.
Topics: Atrial Fibrillation; Electrocardiography; Heart Rate; Humans; Palpation; ROC Curve
PubMed: 26464292
DOI: 10.1177/2047487315611347 -
Cardiovascular Journal of Africa 2018The correct differentiation of an irregular, narrow-complex tachycardia has crucial implications for the therapeutic management of these conditions. In this article we...
The correct differentiation of an irregular, narrow-complex tachycardia has crucial implications for the therapeutic management of these conditions. In this article we present a differential diagnostic and treatment approach to irregular, narrow-complex tachycardias.
Topics: Action Potentials; Atrial Fibrillation; Diagnosis, Differential; Electrocardiography; Female; Heart Conduction System; Heart Rate; Humans; Middle Aged; Predictive Value of Tests; Prognosis; Tachycardia, Supraventricular; Time Factors
PubMed: 30067274
DOI: No ID Found -
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 -
ACS Sensors Sep 2022As the highest percentage of global mortality is caused by several cardiovascular diseases (CVD), maintenance and monitoring of a healthy cardiovascular condition have... (Review)
Review
As the highest percentage of global mortality is caused by several cardiovascular diseases (CVD), maintenance and monitoring of a healthy cardiovascular condition have become the primary concern of each and every individual. Simultaneously, recent progress and advances in wearable pressure sensor technology have provided many pathways to monitor and detect underlying cardiovascular illness in terms of irregularities in heart rate, blood pressure, and blood oxygen saturation. These pressure sensors can be comfortably attached onto human skin or can be implanted on the surface of vascular grafts for uninterrupted monitoring of arterial blood pressure. While the traditional monitoring systems are time-consuming, expensive, and not user-friendly, flexible sensor technology has emerged as a promising and dynamic practice to collect important health information at a comparatively low cost in a reliable and user-friendly way. This Review explores the importance and necessity of cardiovascular health monitoring while emphasizing the role of flexible pressure sensors in monitoring patients' health conditions to avoid adverse effects. A comprehensive discussion on the current research progress along with the real-time impact and accessibility of pressure sensors developed for cardiovascular health monitoring applications has been provided.
Topics: Humans; Monitoring, Physiologic; Wearable Electronic Devices
PubMed: 36036627
DOI: 10.1021/acssensors.2c00942 -
BMJ Open Dec 2021Personal digital devices that provide health information, such as the Apple Watch, have developed an increasing array of cardiopulmonary tracking features which have...
INTRODUCTION
Personal digital devices that provide health information, such as the Apple Watch, have developed an increasing array of cardiopulmonary tracking features which have received regulatory clearance and are directly marketed to consumers. Despite their widespread and increasing use, data about the impact of personal digital device use on patient-reported outcomes and healthcare utilisation are sparse. Among a population of patients with atrial fibrillation and/or atrial flutter undergoing cardioversion, our primary aim is to determine the impact of the heart rate measurement, irregular rhythm notification, and ECG features of the Apple Watch on quality of life and healthcare utilisation.
METHODS AND ANALYSIS
We are conducting a prospective, open-label multicentre pragmatic randomised clinical trial, leveraging a unique patient-centred health data sharing platform for enrolment and follow-up. A total of 150 patients undergoing cardioversion for atrial fibrillation or atrial flutter will be randomised 1:1 to receive the Apple Watch Series 6 or Withings Move at the time of cardioversion. The primary outcome is the difference in the Atrial Fibrillation Effect on QualiTy-of-life global score at 6 months postcardioversion. Secondary outcomes include inpatient and outpatient healthcare utilisation. Additional secondary outcomes include a comparison of the Apple Watch ECG and pulse oximeter features with gold-standard data obtained in routine clinical care settings.
ETHICS AND DISSEMINATION
The Institutional Review Boards at Yale University, Mayo Clinic, and Duke University Health System have approved the trial protocol. This trial will provide important data to policymakers, clinicians and patients about the impact of the heart rate, irregular rhythm notification, and ECG features of widely used personal digital devices on patient quality of life and healthcare utilisation. Findings will be disseminated to study participants, at professional society meetings and in peer-reviewed journals.
TRIAL REGISTRATION NUMBER
NCT04468321.
Topics: Atrial Fibrillation; Atrial Flutter; Electric Countershock; Humans; Multicenter Studies as Topic; Pragmatic Clinical Trials as Topic; Prospective Studies; Quality of Life; Randomized Controlled Trials as Topic
PubMed: 35234659
DOI: 10.1136/bmjopen-2021-054550