Linked Life Data

11341537

Source:http://linkedlifedata.com/resource/pubmed/id/11341537

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-5-8
pubmed:abstractText
A simple and novel technique that utilizes the zero-crossing points of the first time derivative of intra-ventricular pressure (dP/dt) to mark systole, is proposed. Discrete differentiation of the sampled pressure waveform is calculated using a difference equation. Filtration of high-frequency noise in dP/dt is achieved using a low-pass Butterworth filter of order 4 and a cutoff frequency of 10 Hz. The filter is realized digitally using infinite impulse response filter stages. Double filtering of discrete dP/dt is used to eliminate time shifts. The methods are evaluated on data obtained from six large, white, anaesthetised and open chest pigs, instrumented with a conductance catheter. The zero-crossing points of the filtered dP/dt compare very well with the R-waves of the electrocardiogram (ECG) as markers of systole. The mean error is 1.3% of the duration of the heartcycle. Significantly, our results provide a solution to a problem often encountered with multiuse pressure-volume catheters when an ECG signal cannot be obtained. In this situation, the zero-crossing points of dP/dt, rather than the R-waves of the ECG, can be used as a marker of systole, thus enabling the construction of end-systolic pressure-volume relations to assess cardiac contractility.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0018-9294
pubmed:author
pubmed:issnType
Print
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
606-10
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
A novel and simple technique to allow detection of the position of the R-waves from intraventricular pressure waveforms: application to the conductance catheter method.
pubmed:affiliation
Department of Physiology, The Medical School, The University of Birmingham, Edgbaston, UK. a.h.al-khalidi@bham.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't