A 4-month-old Domestic Shorthair cat with no clinical signs was referred for further examination of a heart murmur. An echocardiogram revealed marked right atrial dilation, extending into the left hemithorax. Computed tomography angiography was conducted to investigate further, which revealed a balloon-shaped, contrast-filled cavity on the cranial and left side of the chest that connected to the right atrium through a narrow passage. This was diagnosed as a congenital right atrial diverticulum. Treatment included clopidogrel to reduce the risk of thrombus formation. Two months after the initial diagnosis, castration surgery was successfully performed without complications. The cat died suddenly at home 10 months after diagnosis. To the authors' knowledge, this is the first right atrial diverticulum reported in a cat.

中文翻译：

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小猫先天性右心房憩室

一只 4 个月大的家养短毛猫没有临床症状，因心脏杂音被转诊做进一步检查。超声心动图显示右心房明显扩张，延伸至左半胸。为了进一步研究，进行了计算机断层扫描血管造影，结果显示在胸部的颅骨和左侧有一个气球状的、充满造影剂的空腔，通过狭窄的通道与右心房相连。诊断为先天性右心房憩室。治疗包括氯吡格雷以降低血栓形成的风险。初次诊断两个月后，去势手术成功进行，没有出现并发症。确诊10个月后，这只猫在家中突然死亡。据作者所知，这是猫中首次报道的右心房憩室。