What is hepatic arteriovenous malformation in dogs and cats?

It is a congenital or acquired abnormality of the hepatic blood vessels that can alter blood flow within the liver and impair liver function. Diagnosis typically requires blood tests, biochemistry, and imaging; ask your vet about the specific tests needed.

What tests are needed to assess the condition?

Common tests include a full blood count, biochemistry panel, urinalysis, and abdominal ultrasound or CT imaging; a biopsy may be arranged by a specialist if necessary.

What are the treatment options and approximate cost?

Treatment ranges from monitoring and medication to vascular intervention or surgery depending on the severity. Costs vary considerably — it is best to ask the treating clinic or specialist for an estimate.

How much do the tests and treatment usually cost?

Costs vary by clinic and region — ask your vet for an estimate before proceeding.

Disease Guide

Liver Arteriovenous Malformation in Dogs & Cats: Symptoms, Imaging & Treatment [2025]

Hepatic arteriovenous malformation can cause portal hypertension and abnormal liver function; severe cases may require surgery or interventional treatment.

Take 1 minute to check the symptoms first

Last updated: 2026/01/05

Pethealthmap editorial team

Sources: ACVIM, National Taiwan University Veterinary Hospital, Taiwan Society of Veterinary Internal Medicine

When to See a Vet

Seek immediate veterinary care (emergency)

•Persistent lethargy that is hard to rouse from, or abnormal behavior
•Repeated heavy vomiting with inability to eat for more than a day
•Noticeably distended abdomen, or flinching away when it is touched

Schedule a clinic visit soon (within 24–72 hours)

•Markedly reduced appetite lasting more than two days
•Decreased activity, unwillingness to play or go for walks
•Recurrent diarrhea or persistent blood and mucus in the stool

01What Symptoms Indicate a Problem?

Hepatic arteriovenous malformation in dogs and cats commonly presents as non-specific, generalised signs of illness that may appear gradually or occur intermittently.

Changes in mental alertness — more drowsy or less responsive than usual
Reduced activity level, reluctance to play or go for walks
Persistent loss of appetite or picky eating lasting more than two days
Repeated vomiting or inability to keep food down
Diarrhoea or changes in stool consistency, possibly accompanied by weight loss
Changes in water intake or urination frequency that warrant further evaluation

02How to Assess the Situation at Home: What to Monitor and When to Seek Emergency Care

Observing and recording key information at home before the visit helps your vet quickly understand how the condition has progressed.

Record changes in alertness and activity level once a day, noting specific behavioural changes
Note daily food intake, when reduced appetite started, and how many days it has persisted
Count and record the number of vomiting episodes, what was vomited, and when they occurred
Observe diarrhoea frequency, stool consistency, and whether blood or mucus is present
Weigh your pet weekly and track the trend to bring to the vet for comparison
Record daily water intake and times of excessive drinking to share at the appointment

03How Will the Vet Make a Diagnosis? Common Diagnostic Tests

Your vet will use a physical examination together with laboratory and imaging tests to assess liver function and the distribution of vascular abnormalities.

Full physical examination

abdominal palpation to identify liver enlargement or areas of tenderness

Complete blood count (CBC)

evaluate blood cell values and assess for systemic inflammation

Biochemistry panel

check liver enzyme levels and metabolic function (hepatic function assessment)

Urinalysis

rule out metabolic or renal issues

Imaging (ultrasound, CT)

evaluate hepatic vascular anatomy and identify lesions

Tissue biopsy

arranged by a specialist if necessary to confirm pathology

04How Is It Treated and Managed? Medications, Dietary Adjustments & Care Guide

Treatment may include intervention or surgery, along with dietary adjustments and long-term liver function monitoring.

Determine based on test results whether vascular intervention or surgery is required
Adjust diet according to findings to reduce hepatic workload and support nutritional management
Use medications to manage associated symptoms and monitor liver function indices regularly
Schedule regular follow-up visits after surgery or intervention, including blood tests and imaging
Home care should focus on rest and avoiding high-fat or irritating foods
Refer to a hepatobiliary or interventional specialist centre for further evaluation if necessary

05What to Prepare Before the Vet Visit: Key Information to Help Your Vet Identify the Cause

Record the onset, frequency, and details of each symptom for the vet's reference

List observations of daily food intake, number of vomiting episodes, and diarrhoea frequency

Bring recent weight records or weigh-in results to show the trend

Bring a list of all current medications, supplements, and health products

Bring copies or photos of any previous imaging or laboratory reports for reference

If symptoms persist or worsen, arrange a specialist consultation as soon as possible

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.