Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-5-10
pubmed:abstractText
Pressure overload cardiac hypertrophy may be a compensatory mechanism to normalize systolic wall stress and preserve left ventricular (LV) function. To test this concept, we developed a novel in vivo method to measure myocardial stress (sigma)-strain (epsilon) relations in normal and hypertrophied mice. LV volume was measured using two pairs of miniature omnidirectional piezoelectric crystals implanted orthogonally in the endocardium and one crystal placed on the anterior free wall to measure instantaneous wall thickness. Highly linear sigma-epsilon relations were obtained in control (n = 7) and hypertrophied mice produced by 7 days of transverse aortic constriction (TAC; n = 13). Administration of dobutamine in control mice significantly increased the load-independent measure of LV contractility, systolic myocardial stiffness. In TAC mice, systolic myocardial stiffness was significantly greater than in control mice (3,156 +/- 1,433 vs. 1,435 +/- 467 g/cm(2), P < 0.01), indicating enhanced myocardial contractility with pressure overload. However, despite the increased systolic performance, both active (time constant of LV pressure decay) and passive (diastolic myocardial stiffness constant) diastolic properties were markedly abnormal in TAC mice compared with control mice. These data suggest that the development of cardiac hypertrophy is associated with a heightened contractile state, perhaps as an early compensatory response to pressure overload.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H2190-7
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Heart size-independent analysis of myocardial function in murine pressure overload hypertrophy.
pubmed:affiliation
Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't