A 6 month old mixed breed dog presented for evaluation of an intra-hepatic portosystemic shunt diagnosed ultrasonographically. The puppy seizured upon recovery from anesthesia for routine castration three months prior to evaluation and bloodwork collected at that time was consistent with a portosystemic shunt. Medical management with a low protein diet and lactulose was initiated, and the patient’s clinical signs resolved with therapy. Ultrasound was suspicious for a right divisional intra-hepatic shunt. Given the patient’s young age, and apparent immature body size, delayed CT angiography and definitive therapy was recommended until the patient approached more mature body size. However, the patient developed ventral cervical edema and ascites from severely decreased colloid osmotic pressure (COP) secondary to severe hypoalbuminemia (0.8 mg/dL) over the course of several weeks. Spironolactone therapy was instituted, which resolved the patient’s edema.
Why is CT angiography recommended to be delayed until patients have reached mature body size?
Why was spironolactone prescribed? Could another diuretic have been used?
Images from CT angiography are below, and progress from caudal to cranial. A 3D reconstruction of the shunt is also shown.
Is this a left divisional, right divisional, or central divisional intrahepatic shunt?
Based on the CT angiography appearance of this shunt, what are the treatment options for this patient?
Prior to definitive shunt treatment, should additional medical therapy be instituted? Why or why not?
Percutaneous coil embolization (PTCE) was felt to the best treatment option for this patient and was performed routinely via access from the right jugular vein. Baseline portal pressure measurement for this patient was 7 cm H2O. After placement of 12 thrombogenic coils of differing sizes, the portal pressure increased to 13 cm H2O.
What anatomical landmarks must be considering when sizing and placing caval stents?
What is considered a safe change in portal pressure after placement of thrombogenic coils? Could more coils have been placed in this patient?
What percentage of patients require a second PTCE for additional coils?
What are the immediate post-operative concerns for PTCE patients?