Document Detail

Fibrillatory conduction in the atrial free walls of goats in persistent and permanent atrial fibrillation.
MedLine Citation:
PMID:  20937721     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Over a time course of months, the stability of atrial fibrillation (AF) gradually increases and the efficacy of pharmacological cardioversion declines both in humans and in animal models. Changes in fibrillatory conduction over this period largely are unexplored.
METHODS AND RESULT: Goats were instrumented with an atrial endocardial pacemaker lead and a burst pacemaker. AF was maintained for 3 weeks (short-term AF [ST], n = 10) or 6 months (long-term AF [LT], n = 7). AF could be cardioverted pharmacologically at the early time point (persistent AF), but not at the later time point (permanent AF). At follow-up, a high-resolution mapping electrode was used to record epicardial conduction patterns in the free walls of the right atrium (RA) and left atrium (LA). A new method for mapping of fibrillation waves was used to describe AF conduction patterns. Wavefronts propagated uniformly during slow pacing in both groups, although conduction velocity was significantly lower in the LT group (LA, 93 ± 14 versus 72 ± 10 cm/s; RA, 94 ± 8 versus 78 ± 8 cm/s). Median AF cycle length (AFCL) was not significantly different between the groups. However, the LT group showed highly complex activation patterns during AF, with an increased number of simultaneously propagating waves (LT group RA, 8.4 ± 3.0 waves/AFCL; LA, 12.8 ± 2.4 waves/AFCL; versus ST group RA, 4.3 ± 2.2 waves/AFCL; LA, 4.5 ± 2.5 waves/AFCL). Fibrillation waves in the LT group showed pronounced dissociation with large activation time differences. The incidence of waves newly appearing within the recording area also was increased in both atria. These alterations in conduction were accompanied by myocyte hypertrophy and increased endomysial fibrosis.
CONCLUSIONS: Long-term AF in goats leads to dissociated conduction in the atrial free walls that may contribute to increased AF stability.
Sander Verheule; Els Tuyls; Arne van Hunnik; Marion Kuiper; Ulrich Schotten; Maurits Allessie
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-10-11
Journal Detail:
Title:  Circulation. Arrhythmia and electrophysiology     Volume:  3     ISSN:  1941-3084     ISO Abbreviation:  Circ Arrhythm Electrophysiol     Publication Date:  2010 Dec 
Date Detail:
Created Date:  2010-12-15     Completed Date:  2011-02-23     Revised Date:  2012-02-03    
Medline Journal Info:
Nlm Unique ID:  101474365     Medline TA:  Circ Arrhythm Electrophysiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  590-9     Citation Subset:  IM    
Department of Physiology, Faculty of Medicine, Maastricht University, Maastrict, The Netherlands.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Atrial Fibrillation / physiopathology*
Body Surface Potential Mapping / methods*
Disease Models, Animal
Disease Progression
Follow-Up Studies
Heart Atria / innervation*,  physiopathology
Heart Conduction System / physiopathology*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Noninvasive diagnosis of electroanatomic abnormalities in arrhythmogenic right ventricular cardiomyo...
Next Document:  Determinants of postinfarction ventricular tachycardia.