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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1990-6-8
|
| pubmed:abstractText |
Preload affects left ventricular pump function through the Frank-Starling curve by changing sarcomere length. However, common indices of preload, such as end-diastolic volume, or pressure, or stress, do not necessarily reflect sarcomere length. Ultimately, this depends on the elastic stiffness constant (k) and end-diastolic stress (sigma), which are not in simple relation with the above mentioned indices. An index of preload is proposed, (k sigma)(1/k). This index has been evaluated in 148 patients with different degrees of hemodynamic overload, and in 24 normal subjects. The preload index was found to be 1.448 +/- 0.034 in normal subjects. However, in the other patients evaluated preload index increased in mitral insufficiency (1.490 +/- 0.035), in decompensated aortic insufficiency (1.490 +/- 0.89) and in dilated cardiomyopathy (1.52 +/- 0.125), and markedly decreased in aortic stenosis (1.367 +/- 0.039) and in hypertrophic cardiomyopathy (1.41 +/- 0.034). It was always positively related to the afterload, measured as peak systolic stress. No positive relationship was found with end-diastolic volume nor pressure. Therefore, preload as a compensatory mechanism is differently recruited in response to various degrees of hemodynamic overload and parallels the afterload, in agreement with the concept of preload-afterload mismatch.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jan
|
| pubmed:issn |
0021-4868
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
31
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
1-13
|
| pubmed:dateRevised |
2008-11-21
|
| pubmed:meshHeading |
pubmed-meshheading:2335841-Aortic Valve Insufficiency,
pubmed-meshheading:2335841-Aortic Valve Stenosis,
pubmed-meshheading:2335841-Blood Pressure,
pubmed-meshheading:2335841-Cardiac Output,
pubmed-meshheading:2335841-Cardiac Volume,
pubmed-meshheading:2335841-Cardiomyopathy, Dilated,
pubmed-meshheading:2335841-Cardiomyopathy, Hypertrophic,
pubmed-meshheading:2335841-Hemodynamics,
pubmed-meshheading:2335841-Humans,
pubmed-meshheading:2335841-Mitral Valve Insufficiency,
pubmed-meshheading:2335841-Models, Cardiovascular,
pubmed-meshheading:2335841-Myocardial Contraction,
pubmed-meshheading:2335841-Stroke Volume,
pubmed-meshheading:2335841-Ventricular Function
|
| pubmed:year |
1990
|
| pubmed:articleTitle |
The concept of preload and its evaluation in the intact left ventricle.
|
| pubmed:affiliation |
Department of Clinical Medicine, University of Padova Medical School, Italy.
|
| pubmed:publicationType |
Journal Article
|