Linked Life Data

3449503

Source:http://linkedlifedata.com/resource/pubmed/id/3449503

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1988-6-16
pubmed:abstractText
We tested the multiple-wavelet hypothesis by studying the initiation and maintenance of atrial fibrillation in normal mules, horses, cows, calves, and goats. Persistence of atrial fibrillation in animals with a large atrial mass was compared with results in adult goats and calves having a smaller atrial mass. Atrial stimulation in clinically normal cows, mules, calves, and goats was accomplished using an intra-atrial stimulating catheter with rapid atrial pacing (30/s). Once initiated, atrial fibrillation persisted for 95,120,125 min, 3 days, and 8 weeks in five adult cows, respectively. In contrast, in five calves, atrial fibrillation failed to persist for more than a few minutes. Similar results were found in the small atria of adult goats, indicating that atrial size rather than maturity of the atrial myocardium was responsible. In addition, to demonstrate that this was not a species-dependent phenomenon, it was shown in adult mules that atrial fibrillation could persist for 24 h or more once initiated. These studies are consistent with the multiple-wavelet hypothesis for initiation and maintenance of atrial fibrillation. We also studied the ventricular response in atrial fibrillation. We found that as many as nine consecutive atrial responses can be concealed within the atrioventricular (AV) node associated with a long R-R interval during atrial fibrillation. Although concealment of rapid atrial activity normally occurred in the AV node, one case of infranodal block was observed. It has also been suggested that subsidiary AV junctional pacemakers may be the cause of the ventricular irregularity. However, our experimental studies using microelectrodes in isolated tissue and extracellular bundle of His recordings in intact animals failed to demonstrate that this mechanism was responsible for the irregularity of the ventricular response in atrial fibrillation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0935-736X
pubmed:author
pubmed:issnType
Print
pubmed:volume
2
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
32-9
pubmed:dateRevised
2008-2-26
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Electrophysiological studies on atrial fibrillation.
pubmed:affiliation
School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't