Linked Life Data

4031277

Source:http://linkedlifedata.com/resource/pubmed/id/4031277

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1985-10-4
pubmed:abstractText
Doppler echocardiographic methods for measuring volumetric flow through the aortic, pulmonary and mitral valves provide the cardiologist with several potentially interchangeable noninvasive methods for determining cardiac output. In addition, comparison of flow differences through individual valves offers the potential to quantitate shunt flow and regurgitant volumes. To date, however, no study has compared the relative accuracies of each of these flow measurements in a controlled experimental setting. Therefore, in this study, Doppler echocardiography was used to measure aortic, pulmonary and mitral valve flows in seven open chest dogs on right atrial bypass where forward cardiac output was precisely controlled with a roller pump. Correlations with roller pump output were better for Doppler measurements of aortic (r = 0.98, SD = 0.3) and mitral (r = 0.97, SD = 0.3) than for pulmonary (r = 0.93, SD = 0.5) valve flow. Interobserver reproducibility was also better for aortic (r = 0.94) and mitral (r = 0.97) than for pulmonary (r = 0.88) valve flow measurements. All valves showed flow-related increases in cross-sectional area, but the slope of this response was variable: 0.05, 0.16 and 0.21 for the aortic, the pulmonary and the mitral valve, respectively. Increased forward flow through the aortic valve, therefore, was manifested primarily by an increase in velocity, whereas increasing flow through the pulmonary and mitral valves produced more significant area changes with correspondingly smaller increases in the velocity component. Recalculation of Doppler-determined outputs, assuming a fixed valve area for the entire range of flows, resulted in a decreased correlation with roller pump output. Both velocity and valve area should be measured at each flow rate for greatest accuracy in volumetric flow calculations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0735-1097
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
653-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Variable effects of changes in flow rate through the aortic, pulmonary and mitral valves on valve area and flow velocity: impact on quantitative Doppler flow calculations.
pubmed:publicationType
Journal Article, Comparative Study