Linked Life Data

4042297

Source:http://linkedlifedata.com/resource/pubmed/id/4042297

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1985-11-21
pubmed:abstractText
The identification of afterdepolarizations and their relationship to arrhythmias in vivo is not available. Experiments were undertaken to determine whether afterdepolarizations could be detected in monophasic action potentials (MAPs) recorded in vivo and whether they were related to arrhythmias in an intact canine preparation of the long QT syndrome. Isolated cardiac tissues from six dogs were studied to validate the technique. In simultaneous MAP and transmembrane recordings, afterdepolarizations induced with barium (early) or acetylstrophanthidin (delayed) were detected in MAPs when present in microelectrode recordings. MAPs were then recorded in situ in eight dogs with cesium chloride-induced long QT syndrome associated with ventricular arrhythmias. Afterdepolarizations were identified in each of the dogs and were similar to early afterdepolarizations identified in vitro; they occurred during phase 3 and were attenuated during overdrive pacing. The afterdepolarizations were closely related to arrhythmias: (1) afterdepolarizations always preceded ventricular arrhythmias, (2) the coupling intervals (CI) of the afterdepolarizations (AD) and the ventricular premature beats (VPB) were nearly identical (VPB CI = 1.06 AD CI -10.24; r2 = .87), (3) the take-off potentials of the ventricular premature beats were nearly identical to the amplitude of the afterdepolarizations (take-off potential = 0.98 afterdepolarization amplitude +0.46, r2 = .87), and (4) afterdepolarizations and ventricular arrhythmias resolved concurrently during overdrive pacing and with time. Thus, a new catheter technique has been validated and has been used to directly identify afterdepolarizations and triggered activity in vivo.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0009-7322
pubmed:author
pubmed:issnType
Print
pubmed:volume
72
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1092-103
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Cesium chloride-induced long QT syndrome: demonstration of afterdepolarizations and triggered activity in vivo.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't