Atrial Fibrillation Cycle Length and Atrial Size in Horses with and without Recurrence of Atrial Fibrillation after Electrical Cardioversion. (24th February 2014)

• Record Type: Journal Article
• Authors: De Clercq, D.; Decloedt, A.; Sys, S.U.; Verheyen, T.; Van Der Vekens, N.; van, G.
• Is Part Of: Journal of veterinary internal medicine. Volume 28:Number 2(2014:Mar./Apr.)
• Page Start: 624
• Page End: 629
• Publication Date: 2014-02-24
• Subjects: Veterinary medicine -- Periodicals; 636.0896
• DOI: 10.1111/jvim.12322
• Languages: English
• ISSNs: 0891-6640

Abstract

<abstract abstract-type="main" id="jvim12322-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jvim12322-sec-0001" sec-type="section"> <title>Background</title> <p>Atrial fibrillation (AF) cycle length (CL) and atrial size have been used in humans to characterize electrical and structural remodeling to predict outcome of cardioversion of AF and risk for AF recurrence (rAF).</p> </sec> <sec id="jvim12322-sec-0002" sec-type="section"> <title>Hypothesis</title> <p>Atrial fibrillation cycle length can be determined in horses with AF, and AFCL and atrial size are related to risk for rAF.</p> </sec> <sec id="jvim12322-sec-0003" sec-type="section"> <title>Animals</title> <p>Eighteen horses with naturally occurring AF that were successfully converted to sinus rhythm (SR) by transvenous electrical cardioversion (TVEC).</p> </sec> <sec id="jvim12322-sec-0004" sec-type="section"> <title>Methods</title> <p>Prospective study. Horses with severe valvular regurgitation, left atrial enlargement, or that required sedation for catheter placement were excluded. In all horses intra‐atrial electrograms were recorded and estimated AF duration and echocardiographic parameters were determined before TVEC. The follow‐up time was 1 year after TVEC.</p> </sec> <sec id="jvim12322-sec-0005" sec-type="section"> <title>Results</title> <p>Atrial fibrillation cycle length could be determined in all horses. The AFCL and the shortest 5th percentile (p5) AFCL in horses with rAF (n = 6 or 33%) were (mean ± SD) 157 ± 28 and 134 ± 24 milliseconds, respectively, and in those maintaining SR (n = 12 or 67%) 166 ± 13 and 141 ± 13 milliseconds, respectively. Significant parameters to predict rAF were (1) the ratios of the p5AFCL to the left atrium (LA) sizes corrected to the size of aorta (AO) and (2) LA sizes corrected to the size of AO.</p> </sec> <sec id="jvim12322-sec-0006" sec-type="section"> <title>Conclusions and Clinical Importance</title> <p>Before TVEC, assessment of LA size and atrial electrophysiologic characteristics might help to identify horses at increased risk for AF recurrence.</p> </sec> </abstract>