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Heart Failure Reviews Nov 2022Many patients with persistent, chronic, or frequently recurring paroxysmal atrial fibrillation (AF) may develop a tachycardiomyopathy (TCM) with left ventricular (LV)...
Many patients with persistent, chronic, or frequently recurring paroxysmal atrial fibrillation (AF) may develop a tachycardiomyopathy (TCM) with left ventricular (LV) dysfunction and heart failure (HF), which is reversible upon restoration and maintenance of sinus rhythm, when feasible, or via better and tighter ventricular rate (VR) control. Mechanisms involved in producing this leading cause of TCM (AF-TCM) include loss of atrial contraction, irregular heart rate, fast VR, neurohumoral activation, and structural myocardial changes. The most important of all mechanisms relates to optimal VR control, which seems to be an elusive target. Uncontrolled AF may also worsen preexisting LV dysfunction and exacerbate HF symptoms. Data, albeit less robust, also point to deleterious effects of slow VRs on LV function. Thus, a J-shaped relationship between VR and clinical outcome has been suggested, with the optimal VR control hovering at ~ 65 bpm, ranging between 60 and 80 bpm; VRs above and below this range may confer higher morbidity and mortality rates. A convergence of recent guidelines is noted towards a stricter rather than a more lenient VR control with target heart rate < 80 bpm at rest and < 110 bpm during moderate exercise which seems to prevent TCM or improve LV function and exercise capacity and relieve TCM-related symptoms and signs. Of course, restoring and maintaining sinus rhythm is always a most desirable target, when feasible, either with drugs or more likely with ablation. All these issues are herein reviewed, current guidelines are discussed and relevant data are tabulated and pictorially illustrated.
Topics: Atrial Fibrillation; Catheter Ablation; Heart Atria; Heart Failure; Humans; Ventricular Dysfunction, Left; Ventricular Function, Left
PubMed: 35318562
DOI: 10.1007/s10741-022-10221-1 -
PloS One 2019Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and is associated with increased risk of stroke and congestive heart failure. Lead-I...
Lead-I ECG for detecting atrial fibrillation in patients attending primary care with an irregular pulse using single-time point testing: A systematic review and economic evaluation.
BACKGROUND
Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and is associated with increased risk of stroke and congestive heart failure. Lead-I electrocardiogram (ECG) devices are handheld instruments that can detect AF at a single-time point.
PURPOSE
To assess the diagnostic test accuracy, clinical impact and cost effectiveness of single-time point lead-I ECG devices compared with manual pulse palpation (MPP) followed by a 12-lead ECG for the detection of AF in symptomatic primary care patients with an irregular pulse.
METHODS
Electronic databases (MEDLINE, MEDLINE Epub Ahead of Print and MEDLINE In-Process, EMBASE, PubMed and Cochrane Databases of Systematic Reviews, Cochrane Central Database of Controlled Trials, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database) were searched to March 2018. Two reviewers screened the search results, extracted data and assessed study quality. Summary estimates of diagnostic accuracy were calculated using bivariate models. Cost-effectiveness was evaluated using an economic model consisting of a decision tree and two cohort Markov models.
RESULTS
Diagnostic accuracy The diagnostic accuracy (13 publications reporting on nine studies) and clinical impact (24 publications reporting on 19 studies) results 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%). Cost effectiveness 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 generate ICERs per QALY gained below the £20,000-£30,000 threshold. Kardia Mobile is the most cost effective option in a full incremental analysis. Lead-I ECG tests may identify more AF cases than the standard diagnostic pathway. This comes at a higher cost but with greater patient benefit in terms of mortality and quality of life.
LIMITATIONS
No published data evaluating the diagnostic accuracy, clinical impact or cost effectiveness of lead-I ECG devices for the target population are available.
CONCLUSIONS
The use of single-time point lead-I ECG devices in primary care for the detection of AF in people with signs or symptoms of AF and an irregular pulse appears to be a cost effective use of NHS resources compared with MPP followed by a 12-lead ECG, given the assumptions used in the base case model.
REGISTRATION
The protocol for this review is registered on PROSPERO as CRD42018090375.
Topics: Aged; Aged, 80 and over; Atrial Fibrillation; Cost-Benefit Analysis; Electrocardiography; Female; Humans; Male; Markov Chains; Middle Aged; Primary Health Care; Pulse
PubMed: 31869370
DOI: 10.1371/journal.pone.0226671 -
PloS One 2022Atrial fibrillation (AF) remain a prevalent undiagnosed condition frequently encountered in primary care.
BACKGROUND
Atrial fibrillation (AF) remain a prevalent undiagnosed condition frequently encountered in primary care.
OBJECTIVE
We aimed to find the parameters that optimize the diagnostic accuracy of pulse palpation to detect AF. We also aimed to create a simple algorithm for selecting which individuals would benefit from pulse palpation and, if positive, receive an ECG to detect AF.
METHODS
Nurses from four Cardiology outpatient clinics palpated 7,844 pulses according to a randomized list of arterial territories and durations of measure and immediately followed by a 12-lead ECG, which we used as the reference standard. We calculated the sensitivity and specificity of the palpation parameters. We also assessed whether diagnostic accuracy depended on the nurse's experience or on a list of clinical factors of the patients. With this information, we estimated the positive predictive values and false omission rates according to very few clinical factors readily available in primary care (age, sex, and diagnosis of heart failure) and used them to create the algorithm.
RESULTS
The parameters associated with the highest diagnostic accuracy were palpation of the radial artery and classifying as irregular those palpations in which the nurse was uncertain about pulse regularity or unable to palpate pulse (sensitivity = 79%; specificity = 86%). Specificity decreased with age. Neither the nurse's experience nor any investigated clinical factor influenced diagnostic accuracy. We provide the algorithm to select the ≥40 years old individuals that would benefit from a pulse palpation screening: a) do nothing in <60 years old individuals without heart failure; b) do ECG in ≥70 years old individuals with heart failure; c) do radial pulse palpation in the remaining individuals and do ECG if the pulse is irregular or you are uncertain about its regularity or unable to palpate it.
CONCLUSIONS
Opportunistic screening for AF using optimal pulse palpation in candidate individuals according to a simple algorithm may have high effectiveness in detecting AF in primary care.
Topics: Adult; Aged; Ambulatory Care Facilities; Atrial Fibrillation; Cardiology; Electrocardiography; Heart Failure; Humans; Mass Screening; Middle Aged; Palpation; Pulse
PubMed: 35446875
DOI: 10.1371/journal.pone.0266955 -
Frontiers in Physiology 2022The response to atrial fibrillation (AF) treatment is differing widely among patients, and a better understanding of the factors that contribute to these differences is...
The response to atrial fibrillation (AF) treatment is differing widely among patients, and a better understanding of the factors that contribute to these differences is needed. One important factor may be differences in the autonomic nervous system (ANS) activity. The atrioventricular (AV) node plays an important role during AF in modulating heart rate. To study the effect of the ANS-induced activity on the AV nodal function in AF, mathematical modelling is a valuable tool. In this study, we present an extended AV node model that incorporates changes in autonomic tone. The extension was guided by a distribution-based sensitivity analysis and incorporates the ANS-induced changes in the refractoriness and conduction delay. Simulated RR series from the extended model driven by atrial impulse series obtained from clinical tilt test data were qualitatively evaluated against clinical RR series in terms of heart rate, RR series variability and RR series irregularity. The changes to the RR series characteristics during head-down tilt were replicated by a 10% decrease in conduction delay, while the changes during head-up tilt were replicated by a 5% decrease in the refractory period and a 10% decrease in the conduction delay. We demonstrate that the model extension is needed to replicate ANS-induced changes during tilt, indicating that the changes in RR series characteristics could not be explained by changes in atrial activity alone.
PubMed: 36187793
DOI: 10.3389/fphys.2022.976468 -
Entropy (Basel, Switzerland) Mar 2022How the complexity or irregularity of heart rate variability (HRV) changes across different sleep stages and the importance of these features in sleep staging are not...
How the complexity or irregularity of heart rate variability (HRV) changes across different sleep stages and the importance of these features in sleep staging are not fully understood. This study aimed to investigate the complexity or irregularity of the RR interval time series in different sleep stages and explore their values in sleep staging. We performed approximate entropy (ApEn), sample entropy (SampEn), fuzzy entropy (FuzzyEn), distribution entropy (DistEn), conditional entropy (CE), and permutation entropy (PermEn) analyses on RR interval time series extracted from epochs that were constructed based on two methods: (1) 270-s epoch length and (2) 300-s epoch length. To test whether adding the entropy measures can improve the accuracy of sleep staging using linear HRV indices, XGBoost was used to examine the abilities to differentiate among: (i) 5 classes [Wake (W), non-rapid-eye-movement (NREM), which can be divide into 3 sub-stages: stage N1, stage N2, and stage N3, and rapid-eye-movement (REM)]; (ii) 4 classes [W, light sleep (combined N1 and N2), deep sleep (N3), and REM]; and (iii) 3 classes: (W, NREM, and REM). SampEn, FuzzyEn, and CE significantly increased from W to N3 and decreased in REM. DistEn increased from W to N1, decreased in N2, and further decreased in N3; it increased in REM. The average accuracy of the three tasks using linear and entropy features were 42.1%, 59.1%, and 60.8%, respectively, based on 270-s epoch length; all were significantly lower than the performance based on 300-s epoch length (i.e., 54.3%, 63.1%, and 67.5%, respectively). Adding entropy measures to the XGBoost model of linear parameters did not significantly improve the classification performance. However, entropy measures, especially PermEn, DistEn, and FuzzyEn, demonstrated greater importance than most of the linear parameters in the XGBoost model.300-s270-s.
PubMed: 35327890
DOI: 10.3390/e24030379 -
NPJ Digital Medicine Feb 2021Understanding day-to-day variations in symptoms and medication management can be important in describing patient centered outcomes for people with constipation. Patient...
Understanding day-to-day variations in symptoms and medication management can be important in describing patient centered outcomes for people with constipation. Patient Generated Health Data (PGHD) from digital devices is a potential solution, but its utility as a tool for describing experiences of people with frequent constipation is unknown. We conducted a virtual, 16-week prospective study of individuals with frequent constipation from an online wellness platform that connects mobile consumer digital devices including wearable monitors capable of passively collecting steps, sleep, and heart rate data. Participants wore a Fitbit monitoring device for the study duration and were administered daily and monthly surveys assessing constipation symptom severity and medication usage. A set of 38 predetermined day-level behavioral activity metrics were computed from minute-level data streams for steps, sleep and heart rate. Mixed effects regression models were used to compare activity metrics between constipation status (irregular or constipated vs. regular day), medication use (medication day vs. non-medication day) and the interaction of medication day with irregular or constipation days, as well as to model likelihood to treat with constipation medications based on daily self-reported symptom severity. Correction for multiple comparisons was performed with the Benjamini-Hochberg procedure for false discovery rate. This study analyzed 1540 enrolled participants with completed daily surveys (mean age 36.6 sd 10.0, 72.8% female, 88.8% Caucasian). Of those, 1293 completed all monthly surveys and 756 had sufficient Fitbit data density for analysis of activity metrics. At a daily-level, 22 of the 38 activity metrics were significantly associated with bowel movement or medication treatment patterns for constipation. Participants were measured to have fewer steps on irregular days compared to regular days (-200 steps, 95% CI [-280, -120]), longer periods of inactivity on constipated days (9.1 min, 95% CI [5.2, 12.9]), reduced total sleep time on irregular and constipated days (-2.4 min, 95% CI [-4.3, -0.4] and -4.0 min, 95% CI [-6.5, -1.4], respectively). Participants reported greater severity of symptoms for bloating, hard stool, difficulty passing, and painful bowel movements on irregular, constipation and medication days compared to regular days with no medication. Interaction analysis of medication days with irregular or constipation days observed small increases in severity compared to non-medication days. Participants were 4.3% (95% CI 3.2, 5.3) more likely to treat with medication on constipated days versus regular. No significant increase in likelihood was observed for irregular days. Daily likelihood to treat increased for each 1-point change in symptom severity of bloating (2.4%, 95% CI [2.0, 2.7]), inability to pass (2.2%, 95% CI [1.4, 3.0]) and incomplete bowel movements (1.3%, 95% CI [0.9, 1.7]). This is the first large scale virtual prospective study describing the association between passively collected PGHD and constipation symptoms and severity at a day-to-day granularity level. Constipation status, irregular or constipated, was associated with a number of activity metrics in steps and sleep, and likelihood to treat with medication increased with increasing severity for a number of constipation symptoms. Given the small magnitude of effect, further research is needed to understand the clinical relevance of these results. PGHD may be useful as a tool for describing real world patient centered experiences for people with constipation.
PubMed: 33594206
DOI: 10.1038/s41746-021-00391-x -
International Journal of Cardiology Jan 2019Many patients with atrial fibrillation (AF) present with stroke as their first clinical manifestation and since improved AF screening methods are thus required, we... (Observational Study)
Observational Study
BACKGROUND
Many patients with atrial fibrillation (AF) present with stroke as their first clinical manifestation and since improved AF screening methods are thus required, we investigated whether pulse rate variability parameters predict future AF and cerebrovascular events.
METHODS
In an observational cohort study of 5000 community-resident adults (58% male; 50-84 years), the beat-to-beat variability of suprasystolic brachial blood pressure waveforms was measured with root mean square of successive differences (RMSSD) and irregularity index (IrrIx). Based on outcome-oriented and previously validated thresholds for detecting AF, RMSSD and IrrIx were dichotomised at 100 ms and 7.7%, respectively. Participants were followed up for 4.6 years (median), accruing 249 AF and 120 cerebrovascular events in the total sample (n = 5000), and 133 AF and 90 cerebrovascular events among those without prior AF diagnosis (n = 4296).
RESULTS
In multivariable-adjusted analyses, an elevated RMSSD (>100 ms) or IrrIx (>7.7%) was strongly associated with a higher risk of AF (hazard ratios (HRs) = 2.00-2.95) and cerebrovascular events (HRs = 1.91-2.28), even among people without prior AF diagnosis: HRs for AF = 1.70-2.05 and cerebrovascular events = 2.00-2.28. These associations were strongest in the highest RMSSD tertile >100 ms or IrrIx tertile >7.7%: HRs for AF = 2.32-4.47 and cerebrovascular events = 2.43-3.69. Among those without prior AF diagnosis, the highest categorical net reclassification improvement for 5-year cerebrovascular risk was 14% (95% confidence interval: 7-21%).
CONCLUSIONS
Elevated RMSSD or IrrIx values indicative of the presence of AF predict future AF and cerebrovascular events; more so with increasing pulse irregularity and even among those without prior AF diagnosis.
Topics: Aged; Aged, 80 and over; Atrial Fibrillation; Blood Pressure; Electrocardiography; Female; Follow-Up Studies; Heart Rate; Humans; Incidence; Male; Middle Aged; New Zealand; Population Surveillance; Prognosis; Reproducibility of Results; Risk Assessment; Risk Factors; Stroke; Time Factors
PubMed: 30318296
DOI: 10.1016/j.ijcard.2018.10.026 -
International Journal of Cardiology Aug 2023Photoplethysmography (PPG) is an established technology for detecting pulse rate and pulse wave irregularities. However, whether temporal variations in pulse wave...
OBJECTIVES
Photoplethysmography (PPG) is an established technology for detecting pulse rate and pulse wave irregularities. However, whether temporal variations in pulse wave amplitudes, reflecting a combination of acute hemodynamic or autonomic responses to changes in overall vascular function, carry prognostic information remains unclear. To quantify nocturnal temporal pulse wave amplitude (PWA) attenuations and evaluate its association with long-term cardiovascular (CV) events in a large, racially diverse sample of men and women.
METHODS
Temporal PWA attenuations were determined based on the slopes between the upper and lower envelopes of PPGs derived from overnight polysomnography of 1957 participants (899 men, 1058 women, mean age 68.2 ± 9.1 years) of the Multi-Ethnic Study of Atherosclerosis. The nocturnal PWA attenuation index was defined as the cumulative duration of all PWA attenuation events relative to total sleep duration.
RESULTS
Nocturnal PWA attenuation index was greater in men than in women by almost 13% (16.3 ± 8.9% vs. 14.4 ± 7.9%, p < 0.001). The nocturnal PWA attenuation index was highest in Chinese-American participants (17.9 ± 9.2%) and lowest in African-Americans (13.5 ± 8.1%). During a median follow-up of 4.9 years, 94 CV events occurred. In multivariable Cox proportional hazard analysis adjusted for typical confounders, the nocturnal PWA attenuation index <15.2% was associated with CV events (HR = 1.58 [1.02-2.45], p = 0.042).
CONCLUSIONS
Nocturnal PWA attenuation index is inversely associated with the risk of CV events, particularly in men and African-Americans. The PPG-derived nocturnal PWA attenuation index could be simply obtained from smart wearable consumer devices and may provide a low-cost, accessible and scalable CV risk marker.
Topics: Male; Humans; Female; Middle Aged; Aged; Heart Rate; Polysomnography; Autonomic Nervous System; Heart Disease Risk Factors; Cardiovascular Diseases; Pulse Wave Analysis
PubMed: 37257516
DOI: 10.1016/j.ijcard.2023.05.047 -
International Journal of Molecular... Aug 2023Atrial fibrillation (AF) is a prevalent cardiac condition predominantly affecting older adults, characterized by irregular heartbeat rhythm. The condition often leads to... (Review)
Review
Atrial fibrillation (AF) is a prevalent cardiac condition predominantly affecting older adults, characterized by irregular heartbeat rhythm. The condition often leads to significant disability and increased mortality rates. Traditionally, two therapeutic strategies have been employed for its treatment: heart rate control and rhythm control. Recent clinical studies have emphasized the critical role of early restoration of sinus rhythm in improving patient outcomes. The persistence of the irregular rhythm allows for the progression and structural remodeling of the atria, eventually leading to irreversible stages, as observed clinically when AF becomes permanent. Cardioversion to sinus rhythm alters this progression pattern through mechanisms that are still being studied. In this review, we provide an in-depth analysis of the pathophysiological mechanisms responsible for maintaining AF and how they are modified during sinus rhythm restoration using existing therapeutic strategies at different stages of clinical investigation. Moreover, we explore potential future therapeutic approaches, including the promising prospect of gene therapy.
Topics: Humans; Aged; Atrial Fibrillation; Heart Rate; Tics; Heart Diseases; Heart Atria
PubMed: 37629037
DOI: 10.3390/ijms241612859 -
Journal of Visualized Experiments : JoVE Aug 2018Virtual reality (VR) experiments are increasingly employed because of their internal and external validity compared to real-world observation and laboratory experiments,...
Virtual reality (VR) experiments are increasingly employed because of their internal and external validity compared to real-world observation and laboratory experiments, respectively. VR is especially useful for geographic visualizations and investigations of spatial behavior. In spatial behavior research, VR provides a platform for studying the relationship between navigation and physiological measures (e.g., skin conductance, heart rate, blood pressure). Specifically, physiological measures allow researchers to address novel questions and constrain previous theories of spatial abilities, strategies, and performance. For example, individual differences in navigation performance may be explained by the extent to which changes in arousal mediate the effects of task difficulty. However, the complexities in the design and implementation of VR experiments can distract experimenters from their primary research goals and introduce irregularities in data collection and analysis. To address these challenges, the Experiments in Virtual Environments (EVE) framework includes standardized modules such as participant training with the control interface, data collection using questionnaires, the synchronization of physiological measurements, and data storage. EVE also provides the necessary infrastructure for data management, visualization, and evaluation. The present paper describes a protocol that employs the EVE framework to conduct navigation experiments in VR with physiological sensors. The protocol lists the steps necessary for recruiting participants, attaching the physiological sensors, administering the experiment using EVE, and assessing the collected data with EVE evaluation tools. Overall, this protocol will facilitate future research by streamlining the design and implementation of VR experiments with physiological sensors.
Topics: Humans; User-Computer Interface; Virtual Reality
PubMed: 30222166
DOI: 10.3791/58318