Department of Genetics and Morphology, Brasilia's University, Campus Asa Norte, Brasilia, Brazil.
Department of Medical and Surgical Therapeutics, Faculty of Veterinary, University of Extremadura, Cáceres, Spain.
Heart Rhythm. 2021 Nov;18(11):1990-1998. doi: 10.1016/j.hrthm.2021.07.065. Epub 2021 Jul 30.
Subtle differences exist between dog and human, despite use of the dog as a model for cardiac surgical and electrophysiological research.
The purpose of this study was to investigate the differences in the atrioventricular conduction axis and adjacent structures between dogs and humans.
We prepared 33 human and 5 canine hearts for serial histologic sections of the atrioventricular conduction axis, making correlations with gross anatomic findings. We additionally examined and photographed 15 intact normal human hearts obtained from infants undergoing autopsy. Furthermore, we interrogated a computed tomographic dataset from a human adolescent and from 2 autopsied canine hearts, both with normal cardiac anatomy.
All canine hearts lacked an inferoseptal recess, with the noncoronary leaflet of the aortic valve and the right fibrous trigone having direct attachments to the septal surface of the left ventricular outflow tract. This correlated with an extensive nonbranching component of the ventricular conduction axis, which skirted half of the noncoronary aortic sinus. This anatomic arrangement was observed in 2 of 15 of autopsied infant hearts. In the human hearts with an inferoseptal recess, the relatively shorter nonbranching bundle is embedded within the fibrous tissue forming its right wall.
We found a major difference between canine and the majority of human hearts, namely, the presence or absence of an inferoseptal recess. When this recess is absent, as in the canine heart and in some human hearts, a greater proportion of the atrioventricular conduction axis is found within the circumference of the subaortic outflow tract.
尽管狗被广泛用于心脏外科和电生理研究模型，但狗与人之间仍存在细微的差异。
本研究旨在探讨犬与人心脏房室传导轴及其毗邻结构的差异。
我们准备了 33 个人类和 5 只犬的心脏，用于房室传导轴的连续组织学切片，并与大体解剖学发现相关联。我们还检查并拍摄了 15 例来自接受尸检的婴儿的完整正常人类心脏的图像。此外，我们还检查了来自一名人类青少年和 2 例正常心脏解剖犬的心脏 CT 数据集。
所有犬的心脏均缺乏间隔下隐窝，主动脉瓣的无冠瓣叶和右纤维三角直接附着于左心室流出道的间隔表面。这与心室传导轴的广泛无分支部分相关，该部分绕过无冠窦的一半。这种解剖结构在 15 例尸检婴儿心脏中的 2 例中观察到。在具有间隔下隐窝的人类心脏中，相对较短的无分支束嵌入形成其右侧壁的纤维组织内。
我们发现犬与人的心脏之间存在一个主要差异，即是否存在间隔下隐窝。当不存在该隐窝时，如犬的心脏和一些人类心脏中，房室传导轴的更大比例位于主动脉瓣下流出道的圆周内。
