Stroke in cats 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 cats. Although they can happen in cats of any age, sex or breed, strokes are most likely in older cats over 9 years old and those with certain illnesses.

Strokes are also called cerebrovascular accidents (CVA’s). Strokes make up around 1.5% to 2% of brain-related problems referred to specialist veterinary hospitals. The most common symptoms of a stroke in cats 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 cats who survive the first 30 days after a stroke. Call a vet immediately if you think your cat has had a stroke.

Strokes in cats - what are they and what happens?

A stroke or CVA in cats 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.

Ischaemic strokes

• A solid particle or clot blocks a blood vessel in the brain

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

• Around 80% of strokes in cats are the ischaemic type

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 cats

• 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 issue

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

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

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

Cats 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. The common symptoms of a stroke seen in cats have a sudden onset and include:

• Loss of balance, circling, falling over, arched back

• Loss of coordination and muscle control: occasionally muscle weakness or muscle spasms

• Head tilt

• Jerking eye movements, also called nystagmus

• Abnormal eye position, called strabismus

• Unequal pupil size

• Blindness

• Drowsiness, loss of consciousness, coma

• Seizures, 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, side effects or overdose of medication, such as certain painkillers and seizure medicine, or poisoning.

Risk factors of stroke in cats

Older age is the biggest single risk factor for strokes in cats. Other risk factors include:

• Having other illnesses: kidney disease, diabetes, heart disease, bleeding disorders, cancer, migrating parasite larvae. High blood pressure is a common cause of strokes in humans, and increasingly recognised in cats. It’s usually a complication of another illness.

• Being on certain medications: 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 cats. They won't spread between cats or to other pets and humans. Diagnosis

How do vets diagnose strokes in cats?

The symptoms and sudden onset will often suggest the diagnosis of a stroke in cats. 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 cats treated?

There are rarely specific treatments or cures for strokes in cats. 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

• Fluid therapy to protect other organs and maintain electrolyte (salt) balance in the body

• 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 high blood pressure

How to look after your cat at home after a stroke

Always call a vet if you think your cat has had a stroke. After they have been seen by a vet, you can support them in their recovery at home.

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

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

• Helping your to cat eat drink if needed

• Providing assistance to toilet regularly: using towels or soft harness to support walking, making the litter tray easily accessible and placing your cat on it regularly

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

Tips for reducing the risk of strokes in cats

Strokes can happen in cats 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 your cat having a stroke by keeping them in the best possible health:

• Feed a high quality, balanced diet

• Keep your cat slim, with a healthy body condition score

• Encourage them to do lots of exercise

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

• Take your cat for regular in-person health checks with a vet, at least once a year. This should be done more often as your cat ages.

• Identify and treat other conditions promptly and effectively

When to worry about stroke in cats

Contact your nearest vet practice if your cat:

• 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 cat’s recovery from a stroke

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

• Advice and medication for regular preventive care

• Massage and physiotherapy for convalescing cats