Liver Shunt in a Dog

Patient Information:

Age: 11 weeks old
Species: Canine
Breed: Golden Retriever
Gender: Female

History:

The patient presented for ataxia and anorexia following a change in diet. Bloodwork revealed an elevated ALT (312U/L) and ammonia level, low albumin (2.0g/dL) and mild anemia (27.5%). Pre-prandial bile acids level was high at 106.4umol/L and post 149.2 umol/L.

Ultrasound Findings:

The liver was reduced in size but had a normal shape and echogenicity. In the right lateral liver lobe was a large tortuous aberrant vessel originating from a branch of the portal vein making a hairpin turn toward the caudal vena cava. The abnormal vessel measured up to 17.8mm in width and displayed turbulent blood pattern on color flow Doppler echocardiography. A right divisional intrahepatic portosystemic shunt was suspected.

Image 1. Sagittal plane of the right liver showing an intrahepatic connection of the portal vein branch (PV) with an anomalous dilated hepatic vessel (HV) looping towards the caudal vena cave (CVC).

Images 2. Sagittal plane color flow Doppler image showing turbulent blood flow within the shunt vessel indicated by the mosaic pattern of colors.

Surgical Consultation:

Treatment options included conservative medical management, surgical procedure, and interventional radiology. The decision was made to continue medical therapy (lactulose, antimicrobials, proton pump inhibitor, low protein diet and anticonvulsants as needed) and return when the patient had further grown for additional assessment. Over the next few months, the patient exhibited signs of stunted growth and episodes of seizure activity following dietary indiscretions. At the age of 8 months old, a CT scan with an angiogram contrast study was performed revealing a right divisional intra-hepatic shunt connecting a branch of the portal vein to the caudal vena cava. Percutaneous transjugular coil embolization for intrahepatic shunt attenuation procedure was carried out. Using fluoroscopy, a stent was placed in the vena cava via the jugular vein then embolization coils were placed in the shunt to occlude blood flow. Post-operative complications included transient gastrointestinal bleeding and signs of hepatic encephalopathy which were successfully managed.

Outcome:

Improvement in the hepatic function and mitigation of clinical signs were noticed overtime and shunt medications were tapered down. Additional coils placement has not been needed.

Special thanks to Dr. Grasso atAnimal Medical Center of Loudoun and Dr. Ganjei at VRA for their help with this case.