Strokes in dogs happen when the blood supply to part of their brain is disrupted. Symptoms come on suddenly. They vary in severity from mild to life-threatening. Strokes are the third biggest killer in humans, but they’re relatively uncommon in dogs. Although they can happen in dogs of any age sex or breed, strokes are most likely in older dogs and those with certain illnesses.

Strokes or cerebrovascular accidents (CVA’s) in dogs make up around 1.5% to 2% of brain-related problems referred to specialist veterinary hospitals. The most common symptoms of a stroke in dogs include loss of balance and coordination, jerky eye movements and a head tilt. Although alarming, symptoms usually start to resolve within 24 hours. Prognosis is good for dogs who survive the first 30 days after a stroke. Call a vet immediately if you think your dog has had a stroke.

Strokes in dogs - what are they and what happens?

A stroke or CVA in dogs describes signs and symptoms that happen when blood supply to part of the brain is interrupted. Brain cells need lots of oxygen to carry out essential functions. If brain tissue doesn't get oxygen from its blood supply, it dies. There are two types of strokes in dogs.

Ischaemic strokes

• Interrupted or reduced blood supply to the brain due to a solid particle or clot blocking a blood vessel.

• The brain tissue that blood vessel supplies doesn't get oxygen and stops working properly or dies completely

• Around 80% of strokes in dogs

Types of blockage include:

• Emboli (fragments or particles) from elsewhere in the body: blood clots, bacteria, cancer cells, protein, fat, air

• Thrombus: clotting within the blood vessel walls. Results from roughening or damage to the blood vessel wall

Brain Haemorrhages

• Bleeding inside the skull. There’s nowhere for blood to go because the skull can't expand.

• Pressure builds up and damages delicate brain tissue. Sometimes brain tissue becomes herniated or pushed outside the usual brain cavity

• Around 15-20% of strokes in dogs

• Trauma: blow to the head or sudden impact

• Tumours that start to bleed: brain tumours or tumours that spread from elsewhere in the body

• Diseases that cause blood clotting problems: liver disease, severe infections, sepsis

• Poisoning: anticoagulant rodenticides (rat bait)

Outcome

• Symptoms of a stroke come on very suddenly and look alarming

• Symptoms don’t usually worsen after the initial episode

• Many patients will start to recover within 12-24 hours and continue recovery over the next 2-6 weeks

• Recovery may be complete or partial

• Stroke symptoms may worsen over the first day if damage spreads out to surrounding brain tissue

• Around 10% of human strokes are fatal. The figure is likely similar in dogs.

• Outlook is good for dogs who survive the first 30 days

How can I tell if my dog has had a stroke?

Dogs can’t tell us if they suffer the milder symptoms of a stroke, such as temporarily losing sight in one eye or strength in a limb. Strokes in dogs usually affect part of the brain called the cerebellum, which controls balance and coordination. The common symptoms of a stroke in dogs have a sudden onset and include:

• Loss of balance, circling, falling over

• Loss of coordination and muscle control. Occasionally muscle weakness.

• Head tilt

• Jerking eye movements, also called nystagmus

• Abnormal eye position, called strabismus

• Blindness

• Drowsiness, loss of consciousness

• Seizures and death

These symptoms are not specific to strokes. Many occur with other diseases affecting the brain or balance system, including vestibular disease, middle or inner ear disease, epilepsy and the side effects of medication, such as certain painkillers or seizure medicine.

Risk factors for stroke in dogs

Older age is the biggest single risk factor for stroke in dogs. Other risk factors include:

• Belonging to certain breeds: Cavalier King Charles Spaniels, Greyhounds

• Having other illnesses: kidney disease, Cushing's disease, hypothyroidism, diabetes, heart disease, bleeding disorders, cancer. High blood pressure is a common cause of strokes in humans, but less common in dogs. It’s usually a complication of another illness.

• Being on certain medication: high doses of steroids such as prednisolone

• Having a previous history of a stroke

Is there a risk to other pets and people?

Strokes happen in individual dogs. They won't spread between dogs or to other pets and humans. Diagnosis

How do vets diagnose strokes in dogs?

The symptoms and sudden onset will often suggest the diagnosis of a stroke in dogs. Further tests may include:

• Neurological examination: checking nerve reflexes, sight, hearing, eye movement

• Otoscope and ophthalmoscope exams: taking a closer look at the ears and eyes respectively

• ECG and heart scan to assess heart function

• Blood tests: general health checks, clotting, infections, some cancers, hormonal imbalances

• Abdominal ultrasound: kidney disease, liver problems, abdominal tumours

• Imaging the brain: MRI, CT scan, special dye tests

How are strokes in dogs treated?

There are rarely specific treatments or cures for strokes in dogs. However chances of survival are increased by prompt supportive care from a vet. The brain is surprisingly good at repairing itself. The goals of treatment are to:

• Resolve underlying causes for interruption of blood supply

• Support the brain and body while the brain works to restore blood flow, repair itself and adapt

Treatment includes:

• Oxygen therapy: to get as much oxygen as possible to damaged brain tissue and to help the healing process

• Medication to reduce brain swelling

• Providing high quality nutrition

• Supporting normal body functions like pooing and peeing

• Physiotherapy: keeping limbs moving, massage

• Treating or reviewing treatment for underlying causes such as Cushing’s disease or high blood pressure.

How to look after your dog at home after a stroke

Always call a vet if you think your dog has had a stroke. After your dog is assessed by a vet and treated, you can continue to support them in their recovery at home afterwards by:

• Giving medicines at the times and dose prescribed by your vet

• Ensuring your dog has access to high quality food and clean drinking water

• Helping your to dog eat drink if needed

• Providing assistance to toilet regularly: using towels or soft harness to support walking

• Providing physical therapy: massage, passively moving limbs to help blood supply and reduce muscle wastage.

Tips for reducing the risk of strokes in dogs

Strokes can happen in dogs of any age for no apparent reason. Just as they may do in humans. So we can't prevent strokes from happening. But you can reduce the risk of stroke by keeping your dog in the best possible health:

• Feed a high quality, balanced diet

• Keep your dog slim, with a healthy body condition score and encourage lots of exercise

• Stay up to date with anti-parasite preventive treatments and vaccinations

• Take your dog for regular in-person health checks with a vet, at least once a year, more often as your dog ages

• Identify and treat other conditions promptly and effectively

When to worry about your dog having a stroke

Contact a vet immediately if your dog:

• Is not moving and not responding to you

• Is having a seizure

• Is suddenly too weak or confused to stand

• Appears suddenly blind

• Keeps rolling or falling over

• Develops a head tilt, or walks in circles

• Has jerky eye movements or their eyes look in an odd position

• Is scuffing their feet or stumbling

Joii can help with:

• Recognising and advising on the diseases that increase risk of stroke

• Helping your dog’s recovery from a stroke

• Weight and exercise management in dogs of all ages and lifestyles

• Advice and medication for regular preventive care

• Massage and physiotherapy for convalescing dogs