Linked Life Data

21148762

Source:http://linkedlifedata.com/resource/pubmed/id/21148762

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2011-2-1
pubmed:abstractText
Congestive heart failure (CHF) predisposes to ventricular fibrillation (VF) in association with electrical remodeling of the ventricle. However, much remains unknown about the rate-dependent electrophysiological properties in a failing heart. Action potential properties in the left ventricular subepicardial muscles during dynamic pacing were examined with optical mapping in pacing-induced CHF (n=18) and control (n=17) rabbit hearts perfused in vitro. Action potential durations (APDs) in CHF were significantly longer than those observed for controls at basic cycle lengths (BCLs)>1,000 ms but significantly shorter at BCLs<400 ms. Spatial APD dispersions were significantly increased in CHF versus control (by 17-81%), and conduction velocity was significantly decreased in CHF (by 6-20%). In both groups, high-frequency stimulation (BCLs<150 ms) always caused spatial APD alternans; spatially concordant alternans and spatially discordant alternans (SDA) were induced at 60% and 40% in control, respectively, whereas 18% and 82% in CHF. SDA in CHF caused wavebreaks followed by reentrant excitations, giving rise to VF. Incidence of ventricular tachycardia/VFs elicited by high-frequency dynamic pacing (BCLs<150 ms) was significantly higher in CHF versus control (93% vs. 20%). In CHF, left ventricular subepicardial muscles show significant APD shortenings at short BCLs favoring reentry formations following wavebreaks in association with SDA. High-frequency excitation itself may increase the vulnerability to VF in CHF.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1522-1539
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
300
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H565-73
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Rate-dependent shortening of action potential duration increases ventricular vulnerability in failing rabbit heart.
pubmed:affiliation
Department of Electrophysiology, Research Center of Montreal Heart Institute, Montreal, QC, Canada. mharada@riem.nagoya-u.ac.jp
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't