Abstract:
:We used finite element analysis to study the relationship between the intraventricular blood conductance and the right ventricular volume. Previous studies reported a quasi-linear dependence between these two quantities. We quantified the effects of the resistivities of the surrounding tissues (e.g. heart wall, lungs) on this relationship and performed simulations for four different right ventricular longitudinal sectional areas to assess the linearity of the relationship. The relationship was most significantly affected by the blood conductivity. However, the effects of the cardiac muscle and the lungs could not be neglected. The dependence of the intraventricular blood conductance on the ventricular volume was found to be non-linear. Although to some extent inaccurate, a linear approximation of this relationship is useful for the development of rate-responsive implantable cardiac pacemakers, where the pacing rate is adjusted based on the need for cardiac output. The cardiac output is computed from the product of the heart rate and the stroke volume. The stroke volume can be estimated by measuring the changes in the intraventricular blood conductance. The electrodes needed for the stroke volume estimation can be placed on the same catheter as those used for pacing. The use of this method for clinical monitoring or diagnosis has to be investigated further given that its errors in the estimation of the stroke volume are considerably larger than those corresponding to standard methods such as dye- or thermo-dilution.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Panescu D,Webster JG,Stratbucker RAdoi
10.1088/0967-3334/15/1/004subject
Has Abstractpub_date
1994-02-01 00:00:00pages
49-56issue
1eissn
0967-3334issn
1361-6579journal_volume
15pub_type
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journal_title:Physiological measurement
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doi:10.1088/0967-3334/29/5/N01
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更新日期:2005-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/2a/001
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2015-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2010-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/25/4/020
更新日期:2004-08-01 00:00:00
abstract::Capillary refill time (CRT) is a simple means of cardiovascular assessment which is widely used in clinical care. Currently, CRT is measured through manual assessment of the time taken for skin tone to return to normal colour following blanching of the skin surface. There is evidence to suggest that manually assessed ...
journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2016-01-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/15/4/010
更新日期:1994-11-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/1/004
更新日期:1993-02-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2006-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/11/003
更新日期:2007-11-01 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aa9d60
更新日期:2018-01-31 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/009
更新日期:1993-08-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2007-04-01 00:00:00
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更新日期:2002-08-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2011-11-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2016-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2013-06-01 00:00:00
abstract::Temporal changes in the impedance spectra of bioelectrodes in contact with skin provide useful data for comparisons between differing electrode materials and skin preparation methods. Traditional impedance measuring systems employ swept frequency methods which will distort results in the impedance spectra of a sample ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/20/1/008
更新日期:1999-02-01 00:00:00
abstract::Fluorine (F) plays an important role in dental health and bone formation. Many studies have shown that excess fluoride (F(-)) can result in dental or skeletal fluorosis, while other studies have indicated that a proper dosage of fluoride may have a protective effect on bone fracture incidence. Fluorine is stored almos...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2012-02-01 00:00:00
abstract::The activPAL™ activity monitor has potential for use in youth with Cerebral Palsy (CP) as it has demonstrated acceptable validity for the assessment of sedentary and physical activity in other populations. This study determined the validity of the activPAL™ activity monitor for the measurement of sitting, standing, wa...
journal_title:Physiological measurement
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更新日期:2014-11-01 00:00:00
abstract::Myoelectrical pattern classification is a crucial part in multi-functional prosthesis control. This paper investigates a discriminant Fourier-derived cepstrum (DFC) and feature-level post-processing (FLPP) to discriminate hand and wrist motions using the surface electromyographic signal. The Fourier-derived cepstrum t...
journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2009-12-01 00:00:00
abstract:OBJECTIVE:Observational studies suggest that obesity might have a Mendelian origin, but it is not clear if gene expression patterns observed in obese subjects are secondary to genetic traits or not. APPROACH:Here we test a transcriptomic signature of obesity previously identified by our group on a large cohort of twin...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aab85a
更新日期:2018-04-26 00:00:00