Abstract:
:The ability to predict if an atrial fibrillation (AF) episode terminates spontaneously or not through non-invasive techniques is a challenging problem of great clinical interest. This fact could avoid useless therapeutic interventions and minimize the risks for the patient. The present work introduces a robust AF prediction methodology carried out by estimating, through sample entropy (SampEn), the atrial activity (AA) organization increase prior to AF termination from the surface electrocardiogram (ECG). This regularity variation appears as a consequence of the decrease in the number of reentries wandering throughout the atrial tissue. AA was obtained from surface ECG recordings by applying a QRST cancellation technique. Next, a robust and reliable classification process for terminating and non-terminating AF episodes was developed, making use of two different wavelet decomposition strategies. Finally, the AA organization both in time and wavelet domains (bidomain) was estimated via SampEn. The methodology was validated using a training set consisting of 20 AF recordings with known termination properties and a test set of 30 recordings. All the training signals and 93.33% of the test set were correctly classified into terminating and sustained AF, obtaining 93.75% sensitivity and 92.86% specificity. It can be concluded that spontaneous AF termination can be reliably and noninvasively predicted by applying wavelet bidomain sample entropy.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Alcaraz R,Rieta JJdoi
10.1088/0967-3334/29/1/005subject
Has Abstractpub_date
2008-01-01 00:00:00pages
65-80issue
1eissn
0967-3334issn
1361-6579pii
S0967-3334(08)51759-Xjournal_volume
29pub_type
杂志文章abstract::Multiple frequency bio-electrical impedance analysis (MFBIA) may be useful for monitoring fluid balance in newborn infants or to provide early prediction of the outcome following perinatal asphyxia. A reference range of data is needed for identification of babies with abnormal impedance values. This was a cross-sectio...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/11/010
更新日期:2006-11-01 00:00:00
abstract::Obesity is associated with abnormal cardiac regulation by the autonomic nervous system (ANS), this being reversed by weight loss. Bariatric (weight-reduction) surgery can induce substantial long-term weight reductions. This study compares the acute influence on ANS control of two different types of bariatric surgery i...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/7/002
更新日期:2009-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/31/6/007
更新日期:2010-06-01 00:00:00
abstract::The objective of this study was to adapt a novel near-infrared diffuse correlation spectroscopy (DCS) flow-oximeter for simultaneous and continuous monitoring of relative changes in cerebral blood flow (rCBF) and cerebral oxygenation (i.e. oxygenated/deoxygenated/total hemoglobin concentration: Δ[HbO2]/Δ[Hb]/ΔTHC) dur...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/10/2135
更新日期:2014-10-01 00:00:00
abstract::The specific heat capacity of tissue is a critical parameter for thermal therapies that act over a long period of time. It is also critical for thermoacoustic signal generation. We present ex vivo measurements of specific heat capacity performed by a dual-pin probe with tight temperature control of the specimen. One 3...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/11/N02
更新日期:2011-11-01 00:00:00
abstract::A new method for the measurement of pulmonary gas exchange during inhalational anaesthesia is described which measures fresh gas and exhaust gas flows using carbon dioxide as an extractable marker gas. The theoretical precision of the method was compared by Monte Carlo modelling with other approaches which use marker ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/1/001
更新日期:2004-02-01 00:00:00
abstract::A new algorithm for classifying ECG recording quality based on the detection of commonly observed ECG contaminants which often render the ECG unusable for diagnostic purposes was evaluated. Contaminants (baseline drift, flat line, QRS-artefact, spurious spikes, amplitude stepwise changes, noise) were detected on indiv...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/9/1435
更新日期:2012-09-01 00:00:00
abstract::Unstable gait is a risk factor for falls. Wearable accelerometers enable remote monitoring of daily walking. Here, new methods for measuring stride-to-stride oscillations are validated against optical motion capture, normative data determined, and dependency on walking speed investigated. Walks by 13 young people (mea...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/5/857
更新日期:2015-05-01 00:00:00
abstract::A nonlinear model predictive controller has been developed to maintain normoglycemia in subjects with type 1 diabetes during fasting conditions such as during overnight fast. The controller employs a compartment model, which represents the glucoregulatory system and includes submodels representing absorption of subcut...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/4/010
更新日期:2004-08-01 00:00:00
abstract::Stroke is a major cause of disability within the western world. About 20% of strokes are a consequence of atheromatous narrowing of the origin of the internal carotid artery. Carotid endarterectomy has been shown to be an effective treatment for those with symptomatic and severe stenosis, provided the risk of death an...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/24/2/310
更新日期:2003-05-01 00:00:00
abstract:OBJECTIVE:Transfer function analysis (TFA) of dynamic cerebral autoregulation (dCA) requires smoothing of spectral estimates using segmentation of the data (SD). Systematic studies are required to elucidate the potential influence of SD on dCA parameters. APPROACH:Healthy subjects (HS, n = 237) and acute ischaemic str...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab7ddf
更新日期:2020-04-17 00:00:00
abstract::Polysomnography (PSG) has been extensively studied for sleep staging, where sleep stages are usually classified as wake, rapid-eye-movement (REM) sleep, or non-REM (NREM) sleep (including light and deep sleep). Respiratory information has been proven to correlate with autonomic nervous activity that is related to slee...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/12/2529
更新日期:2014-12-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/2a/007
更新日期:1994-05-01 00:00:00
abstract::Previous studies have proved that the baroreceptor reflex (baroreflex) control of heart rate can be used for stratification of post-infarction population and, in general, cardiovascular disease populations. Many methods have been proposed to estimate the so-called baroreflex sensitivity (BRS) expressed as ms mmhg-1. M...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/38/1/63
更新日期:2017-01-01 00:00:00
abstract:OBJECTIVE:An artefact-free electrocardiogram (ECG) is essential during cardiac arrest to decide therapy such as defibrillation. Mechanical cardiopulmonary resuscitation (CPR) devices cause movement artefacts that alter the ECG. This study analyzes the effectiveness of mechanical CPR artefact suppression filters to rest...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab9e53
更新日期:2020-11-06 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/10/S02
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/7/1349
更新日期:2014-07-01 00:00:00
abstract::This paper discusses some important issues for the design of electrical impedance measurement systems intended for body fluid shift monitoring, in particular during dialysis treatments. We have studied two common signal generation systems: digital synthesis and carrier recovery. We have found that in prolonged measure...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/16/4/003
更新日期:1995-11-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/16/3a/009
更新日期:1995-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaaeb2
更新日期:2018-03-29 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/20/3/304
更新日期:1999-08-01 00:00:00
abstract:OBJECTIVE:The Actiwatch 2 (AW2) is a wrist-worn accelerometer typically used to measure sleep. Although it can measure physical activity, there is limited evidence supporting its validity. We assessed the validity and reliability of the AW2 to measure sedentary behavior and physical activity (light, moderate, vigorous ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aba80f
更新日期:2020-09-04 00:00:00
abstract::The outside of the skin of the forearm is typically 15 mV more negative than the inside. Stretching the skin causes a reduction in the magnitude of this skin potential V, which we observe as a motion artifact delta V. We seek to determine the origin of this motion artifact by successively stripping 12 layers of the sk...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/17/2/003
更新日期:1996-05-01 00:00:00
abstract::We investigated the utility of ICA for evaluation of fetal rhythm in five uncomplicated twin pregnancies and in five twin pregnancies complicated by fetal arrhythmia. Using objective and subjective criteria, we sought to determine how the signal-to-noise ratio, signal fidelity and interference rejection are affected w...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/1/004
更新日期:2011-01-01 00:00:00
abstract::The effects of mechanical stimulation on hemodynamics, such as due to mechanotransduction in vascular endothelial cells, have been widely discussed recently. We previously proposed a resonance model in which the arterial system is treated as a pressure-transmitting system, and suggested that the application of externa...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/2/004
更新日期:2006-02-01 00:00:00
abstract:OBJECTIVE:Metal exposures have been linked with many adverse health outcomes affecting nearly every system in the body. Exposure to metals has been tracked primarily using blood. Blood metal concentrations have drawbacks as biomarkers stemming from the metals' short biologic half-lives, shipping and storage requirement...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aad947
更新日期:2018-08-31 00:00:00
abstract::Analysis of human eye pupil reactivity is a very valuable diagnostic method used mainly for evaluation of the condition of the autonomic nervous system and the visual system. The paper presents an experimental pupillometer built in the Institute of Physics of the Wroclaw University of Technology. The apparatus makes i...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/1/006
更新日期:2007-01-01 00:00:00
abstract::The results of a preliminary clinical evaluation of a one-frequency electrical impedance tomography (EIT) system enabling static in vivo imaging are presented. The design of the measuring system and image reconstruction software are described. Thirty-one subjects were examined and divided into four clinical groups. Th...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/23/1/304
更新日期:2002-02-01 00:00:00
abstract::Electrical impedance endotomography (EIE) is a modality of impedance imaging where the electrodes are located on an insulating core placed at the centre of the region of interest. The absence of a physical limit to the medium surrounding the probe enables the use of remote electrodes. The present study compares the fe...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/4/001
更新日期:2005-08-01 00:00:00
abstract::Several factors affect the viability of biosensor design. A computer-based model is being developed to enable the sources and effect of noise and variability within the sensor to be analysed. The work now presented details the modelling of the biochemical aspect of the biosensor model-the immunoassay. The equilibrium ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/22/3/318
更新日期:2001-08-01 00:00:00