Vascular Diseases of the Liver Flashcards
what is multiple portosystemic shunts often associated with?
ascites
how many vessels usually make up a congenital portosystemic shunt?
single, large caliber vessel
who primarily gets intrahepatic congenital portosystemic shunts?
large breed dogs
what is a major consequence of congenital portosystemic shunts?
decreased hepatic perfusion
what are the general clinical signs of congenital portosystemic shunts?
stunted growth/failure to thrive
gastrointestinal signs
neurological signs
urinary signs
ptyalism
copper irides
what can be seen on clinical pathology to diagnose a congenital portosystemic shunt?
fasting hyperammonemia
elevated SBA
synthetic failure
microcystic anemia
ammonium biurate crystalluria/urolithiasis
what things are low on a blood panel with a congenital portosystemic shunt?
albumin
cholesterol
glucose
BUN
what characterizes primary hypoplasia of the portal vein?
congenital: abnormally small extra- or intrahepatic portal veins
can the liver be grossly normal with primary hypoplasia of the portal vein?
yes
what is primary hypoplasia of the portal vein with portal hypertension accompanied by?
portal hypertension
ascites
multiple shunts
who is passive hepatic congestion common in?
all species with right congestive heart failure
what does telangiectasia result from?
dilated sinusoidss in areas where hepatocytes have been lost
what is a intrahepatic arteriovenous fistula?
direct anastomosis between the hepatic artery and branches of the portal vein
congenital or acquired
what is portal vein thrombosis associated with?
hypercoagulable states
where is hepatic infarction more common?
margins of liver
what is seen histologically with hepatic infarctions?
zone of coagulative necrosis bordered by inflammatory cells and congestion
what are some common vascular lesions?
portosystemic shunts
chronic passive congestion
telangiectasia
do the two blood sources to the liver mix?
yes: sinusoids
what is prehepatic hypertension?
impaired flow prior to liver
thrombus/embolys
external compression
what is intrahepatic portal hypertension?
increased sinusoidal resistance
what are some causes of portal hypertension?
portal vein thrombosis
portal vein hypoplasia
chronic passive congestion
veno-occlusive disease
hepatic AV fistula
what are the two types of extrahepatic congenital portosystemic shunts?
portocaval: caudal vena cava
porto-azygous: azygous vein
what does abnormal ammonia metabolism lead to?
hepatic encephalopathy
ammonium biurate crystalluria/urolithiasis
what imaging can be done to diagnose a congenital portosystemic shunt?
AUS especially intrahepatic
trans-splenic portal scintigraphy
CT angiography
is primary hypoplasia of the portal vein associated with portal hypertension?
sometimes: non-cirrhotic portal hypertension
what does chronic hepatic congestion look like?
central vein/sinusoidal distension/congestion
persistent hypoxia
replacement fibrosis
nutmeg liver: sinusoidal congestion with fibrosis
how are intrahepatic arteriovenous fistulas classified?
branching pattern
what leads to intrahepatic portal hypertension?
any chronic process that induced extracellular matrix deposition: inflammation, amyloid
what are some causes of hepatic hypoperfusion?
congenital portosystemic shunts
portal vein hypoplasia
chronic passive congestion
veno-occlusive disease
portal vein thrombosis
hepatic infarction
how can an intrahepatic congenital portosystemic shunt be addressed?
thrombogenic coils
how can an extrahepatic congenital portosystemic shunt be addressed?
ameroid constrictors/cellophane bands
is there ascites with congenital portosystemic shunts?
no: normal portal vein pressure
what neurologic signs are seen with congenital portosystemic shunts?
especially postprandial
weakness
somnolence
head pressing
cortical blindness
aggression
seizures
who usually gets primary hypoplasia of the portal vein with portal hypertension?
young large breed dogs
what is histology of primary hypoplasia of the portal vein with portal hypertension indistinguishable from?
congenital portosystemic shunts
