Webmaster Note:  This is presented in its entirety and parts may be very technical in nature

Amy’s Story 

In early June 2015 my son woke me in the middle of the night “Mum something is wrong with Amy come quick”.

I had bought Amy from another breeder intending to show, do agility and eventually breed from her, she had seemed a perfectly normal puppy, and grew well.  She had always been a good eater, was extremely active, well muscled and so full of energy.  From a young age she did suffer from allergies and eventually ended up on hyposenitization vaccines.   Amy had a strange little quirk of standing in her water bowl after running around.  When she was about 12 months of age she had a high temperature and ended up spending the morning at the vet clinic on a drip, given antibiotics she was back to normal very quickly.  From time to time she would have a re occurrence of these temperatures ranging from mild to high.  She also suffered 3 episodes of bleeding from the mouth/nose over a 12 month period.

On the June long weekend in 2015 I took her again to the vet there was something just not right with her but nothing you could really put your finger on, again she had a temperature and a rapid heart rate, the next day the vet started further testing, x-rays showed nothing, but her blood was a little slow to clot.  All blood tests that had been done up to that point in time had not shown much, mainly an elevated white blood count.   Amy did start to become difficult to handle around her mouth at that time, I could no longer give her pills easily she would lock her jaw and then grab my hand in her mouth holding it very hard, the day she had x-rays she bit the vet when he tried to look inside her mouth, this was really uncharacteristic behaviour she was normally such a sweet natured dog.  Amy was sent home with Vit K but we still had no answers I was told to bring her back in a couple of days for more intensive testing, but before that could happen she collapsed in the middle of the night.

We rushed her to our normal vet clinic the vet on duty put her on a drip and told us to take her to the emergency hospital she didn’t know what was wrong, another mad dash in the night to the emergency hospital lots of questions by the team there, but no real idea what was wrong, they kept her overnight and rang early the next morning, Amy was in a serious condition, still no answers but they were taking her by ambulance with a vet and nurse to their main hospital just stay by the phone they said.
   Up to that point Amy had been to 3 different vet practices and seen 5 different vets.  At the time she collapsed she was 18 months old.

That morning Amy’s luck was finally about to change, on duty at the Animal Referral Hospital (ARH) was Dr Sarah Helmond, Sarah had spent time working in America, including time at Cornell University working alongside Dr Sharon Center one of the world’s foremost authorities on Liver diseases.
 When Sarah rang me that morning she was convinced Amy had a liver shunt and said she would treat it as such until proven otherwise, she told me “if I am right you will be able to see her at lunchtime she should be a lot better” and she was, still very weak but Amy was now able to walk out to see me. 

Over the next few days there were lots of tests, bile acid tests showed she did have a compromised liver, blood ammonia tests at 322 was extremely high, ultrasounds and CT Scans were done to determine the type of shunt and position and Sarah was proven right, Amy had a large Congenital Intrahepatic Left Divisional Portosystemic Shunt.

At first we managed her medically, she had lots of regular blood tests done at ARH to make sure she remained stable, she ate a special moderate protein diet - Hills Hepatic food and took several different drugs and most importantly she made a rapid recovery, in fact she has never had any symptoms since.
  I read everything I could find on liver shunts and joined the Liver Shunt & MVD/HMD support group on Yahoo, this is a great group run by some very dedicated people.   From all my research it quickly became clear to me that I couldn’t put Amy thru the open abdominal methods of surgery commonly done to repair liver shunts.   These surgical methods provide excellent outcomes for dogs with extrahepatic shunts but for intrahepatic shunts the surgery is more complicated and the risk high, in fact they have mortality rates up to 28% and major complications as high as 77%, it just didn’t make sense to me to open up an already compromised liver this way, that type of surgery seemed too brutal.

Sarah told me of a man in New York Dr Chick Weisse who was using a minimally invasive procedure to repair Intrahepatic shunts -
Percutaneous Transjugular Coil Embolization (PTCE).   Sending Amy to New York was not possible, there is also a small chance a dog won’t be able to have the procedure and you won’t know that until they start the surgery, so even to bring Chick to Amy was not only expensive but with my luck I thought she would be one of those few not able to have the surgery.  So the search for a surgeon in Australia who was familiar with this procedure began.   I heard about surgeons that had the experience only to find they had now moved overseas.   I found a surgeon that had trained with Dr Weisse but hadn’t yet done the procedure, Sarah found another 2 surgeons but they had done only 3 procedures each.  I am sure they are fine surgeons but we wanted someone with more experience, it is a complex procedure.  Eventually I became resigned to just keeping her alive as long as possible on medical management alone.

Then a series of events happened that changed everything, another Samoyed breeder told me about a heart problem that had occurred in a puppy she had bred, and there were stories of other Samoyeds maybe having heart problems, so I decided to add cardiac checking to the list of health testing done on my dogs.
  Now, I try not to spend too much time on Facebook, but I needed to send a message one day and as I logged on to Facebook up came a notice for a cardiac and eye clinic to be held that coming Saturday run by the Cavalier Club of NSW, so I booked 2 dogs in.   I had made it a practice that whenever I met anyone in the veterinary profession I told them about Amy, I was always hoping that one day someone would say I have done lots of those I can fix that.  And that is exactly what happened that Saturday, Dr Niek Beijerink was doing the cardiac clinic and he said “I can fix that”. 

Niek had trained in the Netherlands at
Utrecht University and worked with liver shunts there before he came to live in Sydney where he is now a cardiology specialist at Sydney University.   Since moving here he has done 8 of these surgeries.  If I had logged onto Facebook 5 minutes earlier that day or even 5 minutes later I would have missed that notice about the clinic. And if that breeder hadn’t told me of her pup’s heart problem I wouldn’t have ever thought to have my dogs tested.  So strange, how things eventually worked out, and only just in time too as Niek left Australia for a 6 month research trip the week after operating on Amy.

On Wednesday 2
nd March 2016 Amy had her surgery almost 9 months since she collapsed.  The surgery went off without a hitch and Dr Sarah Helmond was also there by her side during the procedure. Now we have to wait, in time we will find out if the surgery was successful or if she will require further surgery, approximately 17% of dogs do need further coils added.  But she now has a chance to live a longer life than she might have  with just medical management alone, she is very happy and back playing in the yard with the rest of the dogs and racing up the hill several times a day to check the boundaries of the property for foxes and birds or the neighbours goats that might dare to come too close.

Amy’s symptoms the night she collapsed in June I now know were classic symptoms of Hepatic Encephalopathy (HE) she was drooling, appeared to be blind was stagging eventually lapsing into a coma, later as she recovered at ARH she would press her head into the corner of the crate, but up until that time her symptoms were anything but textbook so it is little wonder none of the vets who had seen her previously ever thought of a Liver Shunt.
 I now know that the standing in water bowls was done to help cool her down, liver shunt dogs can overheat easily.  When she became difficult to handle around her mouth it was probably because she was in pain, people that have Liver Shunts liken HE to having a really bad hangover.  The unexplained fevers are also a sign of Liver Shunts, just not a common symptom. 

Owners and breeders need to be more aware of this awful disease, it is seen in many breeds of dogs, and in those breeds that are over represented, breeders should be doing bile acid tests on puppies before they are sold, no owner should ever have to sit across the table from a vet and hear that their much loved pet may die or likely live a much shortened life.
  This is an awful disease, hard on the dog and hard on the owner. 

The Endovascular (inside the vessel) Procedure performed on Amy

Amy went into hospital the day before for blood tests and assessments.  Leading up to this she had been kept on Levetiracetam (thought to significantly decrease the risk of postoperative seizures) and also Omeprazole (it has been found this drug has reduced post op mortality from 30% to 4%3).  Leading up to surgery she was medically managed on Lactulose, Metronidazole and ate a special Hepatic diet (Hills prescription).   Dogs should be stabilised for a minimum of 4 weeks before surgery.  They should also be at least 5 months of age. (Weisse)   The shunt was measured and the exact anatomy of the shunt determined using a CT angiogram taken previously, usually Dr Beijerink likes to do a CT the day before surgery to ensure the correct stent size can be ordered, but in Amy’s case a variety of sizes were pre ordered to save putting her thru another CT as she had problems with anaesthesia previously.  He was able to then confirm the exact measurements of the shunt during the procedure and select the appropriate size stent.  On the day of the surgery she had a specialist anaesthetist, it is essential to have high quality anaesthesia management during the surgery and there were two surgeons doing the procedure.

Using fluoroscopic guidance, guide wires, are inserted through the jugular vein, a catheter is inserted for measurements of portal pressure and a stent is then deployed within the caudal vena cava covering the mouth of the shunt, this will hold the coils in place and stop them migrating.
 The stent used is the same type used in human heart surgery.   A catheter is then passed thru the stent into the shunt and coils are added one at a time, it is a fine line between sufficient coils and too many so portal pressure is monitored closely with the placement of the stent and each coil, there are potential risks if the pressure goes too high.  Amy had an only 8 coils, the highest number of coils used so far is 30.  The coils are thrombogenic, so when they are in contact with the blood they produce a clot, and there is a gradual attenuation of the shunt first from the coils alone then from subsequent fibrosis.  This then causes an increase in pressure and blood is now redirected thru the liver as it normally should and eventually there is an increased growth and development of the liver. 

Amy’s procedure took 2 hours, the average stay in hospital is only 2 days.
   It is essential to have a 24hr ICU and quality experienced medical support during this time.   There weren’t any stitches needed it was only a 2mm incision, I couldn’t even see a mark on her neck.

There are possible complications 13% of dogs have complications that occur in the first week, including seizures/neurological signs, suspected portal hypertension, jugular site bleeding even death.
    But major intraoperative complications occur in less than 5% of dogs.  Survival time after surgery ranges from 0 to 3411 days, with the median survival time >6 years (2204 days)3.  If the shunt doesn’t block sufficiently then additional coils can be added later, though even incomplete shunt attenuation can still see an improvement in the dog’s health, in fact 81% of dogs that have this surgery show an improvement3.    Dogs with Intra-hepatic shunts do have to stay on a gastroprotectant medication for life as it is common for these dogs to have gastric ulceration. 

Overall this is a far safer procedure than other open surgery methods for intrahepatic shunt repairs.  There has however only been one study into the long term outcome of this surgery and that is the 100 dog study done by Dr Weisse 3.   There is a widely held belief that surgery gives a better chance of long term survival than medical management alone. (Greenhalgh JVMA 2010 & 2014).

Judging by comments I read on various dog forums and social media there are still a lot of vets and owners not just in Australia but around the world that aren’t familiar with this PTCE procedure, and often owners of dogs with intrahepatic shunts only hear about the poor prognosis of the open surgical procedures, and so may be less likely to proceed with surgery.

There are Surgeons that do this procedure and also Cardiologists when we were looking for someone to operate on Amy we never thought of looking for a Cardiologists but it makes perfect sense that they could do this surgery as they are very experienced with the equipment used as it is the same that is used in heart surgery.

Some facts about Congenital Portosystemic Shunts

 ·          A liver shunt is a vessel that carries blood around the liver instead of through it, an Intrahepatic shunt is a vessel inside the liver (mainly seen in large breeds), Extrahepatic shunt is a vessel outside the liver (mainly seen in small breeds). 

Intrahepatic shunts are caused by a failure of the vessel that regulates blood flow from the placenta to vital organs like the lungs and heart during fetal development to close.  This vessel should close within a few days of birth in dogs usually 6-9 days (Lamb & Burton 2004).  Extrahepatic shunts are considered a developmental anomaly

 ·         Because of this shunting the liver can't filter out the toxins in the blood and this causes abnormal amounts of ammonia and other substances to accumulate, which eventually affects the brain.   Other organs, especially the intestines and kidneys, are also damaged. This abnormal shunting also causes low portal blood pressure, reduced drug metabolism and leads to eventual liver failure.

 ·         Symptoms can vary some dogs can have lots of symptoms and others only a few.

 In coordination                        circling

head pressing                            lethargy

dementia                                  listlessness

drooling                                   pacing

personality changes                  aggression

drinking lots of water               vomiting

difficulty urinating                   urate crystals (seen in 57% of shunt dogs)4

urinating frequently                 enlarged kidneys

cryptorchidism                         itchy skin           

excessive appetite                     lack of appetite

pica craving unusual foods       small stature runt of litter

reoccurring unexplained infections                 slow recovery from anaesthesia

exacerbation of clinical signs after eating       seizures

CPPS has been reported in 110 of 201 (55%) breeds of dogs.

·       The oldest dog first diagnosed with CPSS was 13 years old.  This fact is interesting as not all dogs get very sick and some are able to survive till they are older before showing problems.   In fact it is thought 20% of affected dogs are asymptomatic (Center). 

Is it Genetic

Studies continue to be done now on various breeds but when the prevalence of a disease is higher in one breed than the general population then a genetic influence is suspected.   Many authors have shown that congenital shunts are more frequent in purebred dogs and many breeds have been shown to be predisposed to it.  Affected dogs should not be bred from and because the mode of inheritance is not known it is best to avoid breeding parents of affected dogs (Tobias).

 A retrospective study done on 233 dogs and 9 cats presented at the University Veterinary Centre, Sydney  found breeds that were significantly over-represented included Maltese, Silky Terrier, Australian Cattle Dog, Bichon Frise, Shih Tzu, Miniature Schnauzer, Border Collie, Jack Russell Terrier, Irish Wolfhound and Himalayan Cat.  Old English Sheepdogs had also previously been reported as predisposed to Shunts by this University.  42 out of 113 breeds presented to the UVCS during the period of the study were represented by at least 1 individual with a portosystemic shunt1.

 Table 1. Details of numbers, sex, observed and expected incidence of the breeds that presented most commonly with congenital portosystemic shunts, and those that were significantly over-represented in the present study.

WEBMASTER'S Note: The Yorkshire Terrier has a 36% higher risk of having a Liver Shunt than all other breeds combined






Observed Incidence

Expected Incidence

Odds Ratio

Confidence Interval

P Value

Irish wolfhound


















Silky Terrier








< 0.0001

Bichon Frise








< 0.0001

Shih Tzu









Australian Cattle Dog








< 0.0001

Border Collie









Jack Russell


















Toy and Miniature Poodle









Golden Retriever





























a Includes cross breeds, # - females significantly over-represented when compared with other breeds (P = 0.03)

 A study done over a 22 year period in America compared the diagnoses of CPSS in purebred dogs with mixed breed dogs, Samoyeds were found to be 2.9% more likely to have a shunt than a mixed breed dog in that study, there were in fact a total of 33 breeds significantly more likely to have CPSS than a mixed breed.   Congenital portosystemic shunts were reported in 0.18% of all dogs and 0.05% of mixed breed dogs.   In that study they also found the proportion of diagnoses of CPSS was increasing in 1980 the incidence of CPSS in dogs was 1 in 10,000 by 2001 it was 1 in 1000.  This increased odds ratio among specific breed’s supports the hypothesis of a genetic predisposition for CPSS.2

Since coming to Australia Dr Niek Beijerink has operated on Golden Retrievers, Labradors, Irish Wolfhounds,  Samoyed and Cocker

 Spaniel , he only does intra-hepatic shunt surgery not extra-hepatic.  Another specialist in Sydney told me the 3 surgeries he had done 2 were Golden Retrievers and 1 a cross bred.  There have been a few Samoyeds now diagnosed with shunts in Australia, responsible Samoyed breeders now do a paired bile acid test on their puppies before sale so as to not pass this problem on to unsuspecting owners.

I was asked to tell Amy’s story so people could understand that dogs don’t necessarily always display textbook symptoms and to also let people know that another less invasive and safer form of surgery exists for Intrahepatic shunts.

Since being diagnosed Amy has helped at least one other dog, the owners and vets of a 4 ½ yr old dog had previously not been able to work out what was wrong with her (another with vague symptoms), because the latest vet treating this dog knew about Amy’s story he wondered about the possibility of the dog having a shunt and that is exactly what tests have now confirmed.

I am so grateful for the care given to Amy by both the Animal Referral Hospital and Sydney University we are very lucky to have access to quality speciality services for our pets.   

Respectfully submitted:   Rosslyn Rothwell 


1.         GB Hunt  -  Effect of Breed on anatomy of porto-systemic shunts resulting from congenital diseases in dog and cats

2.        Karen M Tobias & BW Rohrbach  -  Association of breed with diagnosis of congenital portosystemic shunts in dogs 2400 cases (1980-2002)

3.        Chick Weisse et al  -  Endovascular evaluation & treatment of Intrahepatic portosystemic shunts in dogs:  100 cases (2001-2011)

4.       Cook Surgery for IHPSS for Resident Forum 2015



All information and images are © copyrighted 2016.
Do not take any portion of this web page without permission!

Website Built & Designed by Stephen Glass © 2016