The few paragraphs to your right pretty much explain about the two different types of liver shunts.
Shunts are uncommon in cats.
We become suspicious of liver shunts when puppies and young dogs just aren't doing well, aren't well developed, and especially if they act dizzy, drunk, or are having seizures. And we are extra suspicious if your pup is a Yorkie.
Blood work, especially a bile acid screen helps us to confirm the diagnosis.
We can make puppies with liver shunts feel better but the only chance for a cure is surgery.
Cardiology Heart disease in Cats, Cardiac Hypertrophy, Valvular disease, Cardiac Insufficiency, Congestive Heart Failure, Heartworm Disease, and a little history about the milestones in treating heart disease
Cats: general information page and directory of diseases and problems specific to cats including vaccine recommendations, leukemia, feline viral infections, feline upper respiratory disease and cats that just aren't feeling well.
Liver A is normal. The blood flowing from the intestinal organs is delivered by the portal vein (represented in blue) to the liver. The blood filters through the liver and then leaves the liver detoxified via the hepatic vein to the vena cava.
Liver B represents a shunt inside the liver. A shunt is simply a vessel that allows blood to bypass the liver tissue and go directly to the heart. All mammals have this shunt while developing in the uterus because the liver is non functional until shortly before birth. The shunt is supposed to close and scar up at birth but sometimes it doesn't. The liver requires a certain amount of blood flow at a certain pressure to work well. If a big enough percentage of blood doesn't go through the liver, then the patient won't thrive and won't grow at a normal rate. And because the blood isn't detoxified, it's common for pups with a liver shunt to have diarrhea, vomiting, and the big clue are CNS signs; acting drunk, seizures, and so forth. This type of liver shunt is common in larger breed dogs, especially Irish Wolfhounds, Labrador Retrievers, Australian Shepherds, Australian cattle dogs, Samoyeds, and Old English sheepdogs. This problem is assumed to be an inherited trait.
Liver C represents a shunt outside the liver. This shunt develops during fetal development in some puppies. This is definitely an inherited trait as this is common in Yorkie Terriers. Yorkies have 36 times greater risk of developing shunts than all other breeds combined. But extrahepatic shunts can be seen in any small breed. The symptoms are the same as with shunts inside the liver, except are likely to be more pronounced.
About other metabolic diseases in cats and dogs.
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