O'Rourke M F, Avolio A P, Nichols W W
Cardiovasc Res. 1986 Jun;20(6):398-402. doi: 10.1093/cvr/20.6.398.
In experiments in 14 anaesthetised kangaroos, 10 developed unexpected ventricular fibrillation and died. In seeking a cause for this, similarities were noted with hypertrophic cardiomyopathy (HC) in man. Like patients with this condition, kangaroos have unexplained left ventricular hypertrophy and are known to be susceptible to sudden death with excitement and exertion. Retrospective analysis of all data showed other features of hypertrophic cardiomyopathy: unusually rapid left ventricular pressure development in systole (peak dP/dt: kangaroo 3602 (SEM472); HC 1947(SEM172) mmHg X s-1), unusually slow left ventricular relaxation (exponential time constant: kangaroo 54(SEM7); HC 63 (SEM5) ms; relaxation time: kangaroo 128(SEM7); HC 112(SEM7) ms), and inappropriately long duration of mechanical systole in relation to ventricular depolarisation (393(SEM21) ms and 214(SEM15) ms respectively). A disparity between the duration of mechanical systole and electrical activation caused a type of incomplete tetanus to develop with ventricular extrasystoles, a phenomenon previously seen in patients with hypertrophic cardiomyopathy. These findings suggest that the kangaroo may be a useful experimental model for studying the fatal rhythm disturbances and abnormal ventricular dynamics in human hypertrophic cardiomyopathy.
在对14只麻醉后的袋鼠进行的实验中，有10只出现了意外的心室颤动并死亡。在寻找其原因时，发现与人类肥厚型心肌病（HC）有相似之处。与患有这种疾病的患者一样，袋鼠存在不明原因的左心室肥厚，并且已知在兴奋和运动时易发生猝死。对所有数据的回顾性分析显示出肥厚型心肌病的其他特征：收缩期左心室压力上升异常迅速（峰值dP/dt：袋鼠为3602（标准误472）；HC为1947（标准误172）mmHg×s-1），左心室舒张异常缓慢（指数时间常数：袋鼠为54（标准误7）；HC为63（标准误5）ms；舒张时间：袋鼠为128（标准误7）；HC为112（标准误7）ms），以及与心室去极化相关的机械收缩期持续时间过长（分别为393（标准误21）ms和214（标准误15）ms）。机械收缩期和电激活持续时间之间的差异导致室性早搏时出现一种不完全强直收缩，这一现象此前在肥厚型心肌病患者中也有观察到。这些发现表明，袋鼠可能是研究人类肥厚型心肌病致命性心律失常和异常心室动力学的有用实验模型。
