Avison Amanda, Physick-Sheard Peter W, Pyle W Glen
Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Canada.
Department of Population Medicine, Ontario Veterinary College, University of Guelph, Canada.
J Mol Cell Cardiol Plus. 2025 May 9;12:100452. doi: 10.1016/j.jmccpl.2025.100452. eCollection 2025 Jun.
This paper reviews the myocardial substrate of horses relative to that of humans and discusses the utility of performance horses as a model of exercise-associated cardiac arrhythmias and sudden cardiac death in athletes. The coronary circulation is similar between the species while coronary artery anomalies and myocardial bridging appear to only be associated with athletic mortality in human athletes and not in performance horses. There are subtle differences in the histology of the sinus and atrioventricular nodes, of unknown clinical significance, while the His bundle is more highly innervated in horses. The equine Purkinje network is much more extensive, contributing to a difference in the mean electrical axis between horses and humans. Differences in ion channel expression have been reported, although they are poorly characterized, and are of unknown clinical significance. However, horses may be a particularly good model to investigate the function of Kv1.5 due to its spontaneous ventricular expression, which is lacking in human ventricles. Similarities in cardiac structure, coronary vasculature, and ability to exercise at high levels makes performance horses a good model to investigate exercise-associated cardiac arrhythmias and sudden cardiac death in athletes. However, differences in myocardial substrate should be taken into consideration when designing studies and interpreting results.
本文回顾了马相对于人类的心肌底物，并讨论了运动马作为运动员运动相关心律失常和心源性猝死模型的实用性。两个物种的冠状动脉循环相似，而冠状动脉异常和心肌桥似乎仅与人类运动员的运动死亡率相关，与运动马无关。窦房结和房室结的组织学存在细微差异，其临床意义尚不清楚，而马的希氏束神经支配更为丰富。马的浦肯野网络更为广泛，这导致了马和人之间平均电轴的差异。尽管对离子通道表达的差异描述甚少且其临床意义不明，但已有相关报道。然而，由于马的心室可自发表达Kv1.5，而人类心室缺乏这种表达，因此马可能是研究Kv1.5功能的特别好的模型。心脏结构、冠状动脉血管系统以及高水平运动能力的相似性使运动马成为研究运动员运动相关心律失常和心源性猝死的良好模型。然而，在设计研究和解释结果时应考虑心肌底物的差异。
