Linked Life Data

7977805

Source:http://linkedlifedata.com/resource/pubmed/id/7977805

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 2
pubmed:dateCreated
1994-12-8
pubmed:abstractText
Electrical and mechanical alternans have often been found to coexist. However, the factors controlling their interdependence are not known. In this study we measure regional electrical and mechanical activity during mechanical alternans to investigate this relationship. Mechanical alternans was induced by rapid atrial pacing in 18 anesthetized, open-chest pigs. Regional segmental contraction and monophasic action potential were measured in three areas of left ventricle using epicardial tripodal strain gauges and suction electrodes. Electrical alternans always accompanied pulsus alternans. The phase of electrical alternans was not related to any measure of regional mechanical activity but did show a constant discordant relation to peak ventricular pressure. This suggested that mechanically dependent changes in action potential duration (mechanoelectric feedback) may be important in modulation electrical alternans. In support of this, pulsus alternans simulated by clamping the proximal aorta on alternate beats was associated with electrical alternans comparable to that produced with rapid atrial pacing. Mechanoelectric feedback modulates regional electrophysiology in the intact heart and may be important in the generation of electrical alternans.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1726-35
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Regional electromechanical alternans in anesthetized pig hearts: modulation by mechanoelectric feedback.
pubmed:affiliation
British Heart Foundation Cardiac Arrhythmia Research Group, Department of Physiology, Charing Cross and Westminster Medical School, London, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't