Heterotaxy Accompanied by Congenital Portosystemic Shunt and Segmental Aplasia of the Caudal Vena Cava with Azygos Continuation in a Dog

Abstract

A 5-month-old male Toy Poodle was presented with neurological dysfunction after eating. The presence of a portosystemic shunt (PSS) was suspected because of the medical history and clinicopathologic findings. Computed tomography (CT) revealed that the positions of the thoraco-abdominal organs were symmetrically reversed from left to right. A single congenital PSS (splenoazygos shunt), segmental aplasia of caudal vena cava, and morphological anomaly of the spleen were found. Heterotaxy was diagnosed. Although surgical attenuation of the PSS was recommended, the dog was treated with medical therapy alone according to the owner’s preference. After approximately 3 years of asymptomatic medical management of PSS, the dog suddenly died at home of unknown causes. It could not be concluded that the cause of the death was related to transposition of the thoraco-abdominal organs.