Buhl Rikke, Carstensen Helena, Hesselkilde Eva Zander, Klein Bjørg Zinkernagel, Hougaard Karen Margrethe, Ravn Kirsten Bomberg, Loft-Andersen Ameli Victoria, Fenner Merle Friederike, Pipper Christian, Jespersen Thomas
Department of Veterinary Clinical Sciences, University of Copenhagen, Taastrup, Copenhagen, Denmark.
Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
J Vet Intern Med. 2018 Jul;32(4):1410-1419. doi: 10.1111/jvim.15137. Epub 2018 May 10.
Atrial fibrillation (AF) is the most common arrhythmia affecting performance in horses. However, no previous studies have quantified the performance reduction in horses suffering from AF.
To quantify the effect of AF on maximum velocity (V ), maximum heart rate (HR ), heart rate recovery (T ), hematologic parameters and development of abnormal QRS complexes.
Nine Standardbred trotters.
Two-arm controlled trial. Six horses had AF induced by means of a pacemaker and 3 served as sham-operated controls. All horses were subjected to an exercise test to fatigue before (SET1) and after (SET2) 2 months of AF or sham. The V and HR were assessed using a linear mixed normal model. Abnormal QRS complexes were counted manually on surface ECGs.
Atrial fibrillation resulted in a 1.56 m/sec decrease in V (P < .0001). In the AF group, HR ± SD increased from 226 ± 11 bpm at SET1 to 311 ± 27 bpm at SET 2. The AF group had higher HR at SET2 compared with controls (P < .0001), whereas no difference between the control and AF groups was observed at SET1 (P = .96). Several episodes of wide complex tachycardia were observed during exercise in 3 of the AF horses during SET2.
Atrial fibrillation resulted in a significant reduction in performance, an increase in HR and development of abnormal QRS complexes during exercise, which may be a risk factor for collapse or sudden cardiac death.
心房颤动（AF）是影响马匹运动能力的最常见心律失常。然而，此前尚无研究对患AF马匹的运动能力下降进行量化。
量化AF对最大速度（V）、最大心率（HR）、心率恢复（T）、血液学参数及异常QRS波群形成的影响。
9匹标准赛马。
双臂对照试验。6匹马通过起搏器诱导产生AF，3匹作为假手术对照。所有马匹在AF或假手术2个月前后均接受运动试验直至疲劳（SET1和SET2）。使用线性混合正态模型评估V和HR。在体表心电图上手动计数异常QRS波群。
AF导致V降低1.56米/秒（P <.0001）。AF组中，HR±SD从SET1时的226±11次/分钟增加到SET2时的311±27次/分钟。与对照组相比，AF组在SET2时HR更高（P <.0001），而在SET1时对照组和AF组之间未观察到差异（P = 0.96）。在SET2期间，3匹AF马在运动过程中观察到几次宽QRS波群心动过速发作。
AF导致运动能力显著下降、HR增加以及运动期间异常QRS波群形成，这可能是虚脱或心源性猝死的危险因素。
