Bharati S, Cantor G H, Leach J B, Schmidt K E, Blake J
Maurice Lev Congenital Heart and Conduction System Center, Palos Heights, IL 60463, USA.
Pacing Clin Electrophysiol. 1997 Mar;20(3 Pt 1):654-63. doi: 10.1111/j.1540-8159.1997.tb03884.x.
Using serial section examination, we studied the conduction system in five Alaskan sled dogs that died suddenly; four during the Iditarod race and one during training. We compared our findings with the conduction system of three sled dogs of similar age that died of natural causes unrelated to the cardiovascular system. The conduction system of sudden death dogs revealed marked fibrosis of the sinoatrial (SA) node and/or its approaches and narrowing of the SA nodal artery in 3 dogs, fibrosis and marked fatty infiltration in and around the AV node in all 5, total isolation and/or tenuous connection of the AV node with its approaches in 4, fat and fibrosis in the AV bundle and bundle branches to a varying degree in all, and focal fibrotic scars in the left ventricle with fat and/or some disarray in 3. The control group revealed mild fibro-fatty changes in the conduction system without fibrotic scar areas in the heart. These findings are similar to the pathological findings in and around the conduction system in cases of sudden death in humans, especially trained athletes. These changes may form an anatomical substrate for an arrhythmic event in susceptible dogs during an altered physiological state.
通过连续切片检查，我们研究了五只突然死亡的阿拉斯加雪橇犬的传导系统；其中四只在艾迪塔罗德狗拉雪橇比赛期间死亡，一只在训练期间死亡。我们将我们的研究结果与三只因与心血管系统无关的自然原因死亡的年龄相近的雪橇犬的传导系统进行了比较。猝死犬的传导系统显示，3只犬的窦房（SA）结及其附近有明显纤维化，窦房结动脉狭窄；所有5只犬的房室结及其周围有纤维化和明显的脂肪浸润；4只犬的房室结与其附近完全隔离和/或连接薄弱；所有犬的房室束和束支均有不同程度的脂肪和纤维化；3只犬的左心室有局灶性纤维化瘢痕伴脂肪和/或部分紊乱。对照组的传导系统有轻度纤维脂肪改变，心脏无纤维化瘢痕区域。这些发现与人类猝死病例，尤其是训练有素的运动员的传导系统及其周围的病理发现相似。这些变化可能为易感犬在生理状态改变时发生心律失常事件形成解剖学基础。
