An 18-month-old Springer Spaniel was presented for investigation of ascites, exercise intolerance and suspected cor triatriatum dexter. Division of the right atrium into two separate chambers by an anomalous perforated membrane consistent with cor triatriatum dexter was confirmed during echocardiography. However, a routine agitated saline contrast (bubble) study yielded results that could not be explained by the congenital heart defect alone. Computed tomography angiography was performed and revealed a dilated ventral internal vertebral venous plexus and a short, dilated vessel in the midlumbar region redirecting blood flow away from the caudal vena cava and into the azygos vein. Balloon dilatation of the orifice within the cor triatriatum dexter membrane successfully reduced pressure within the caudal chamber of the right atrium and enhanced return via the caudal vena cava with subsequent resolution of clinical signs. This case report highlights the use of cross-sectional imaging in dogs with cor triatriatum dexter and unexpected contrast study results, as a means by which concurrent vascular anomalies may be identified.

一只 18 个月大的斯普林格猎犬因腹水、运动不耐受和疑似三心房 dexter 被送去调查。超声心动图证实了与右心房右心房一致的异常穿孔膜将右心房分成两个独立的腔室。然而，一项常规搅动盐水对比（气泡）研究得出的结果不能仅用先天性心脏缺陷来解释。计算机断层扫描血管造影显示腹侧椎内静脉丛扩张，腰中部有一个短而扩张的血管，将血流从尾腔静脉重定向到奇静脉。右心房右心房膜内孔口的球囊扩张成功地降低了右心房尾腔内的压力，并通过尾腔静脉增强了回流，随后临床症状消退。本病例报告强调了在具有右三心体的狗中使用横断面成像和意想不到的对比研究结果，作为一种可以识别并发血管异常的方法。