Hypertension is the medical term for high blood pressure. It is most common in older, obese cats.
This disease can cause injury to the brain, eyes, heart, and kidneys.
Some cases of hypertension are idiopathic (there is no known cause). This is called Primary Hypertension. Some known causes include:
- Heart disease
- Kidney disease: with age, scar tissue grows on the kidneys; the kidneys shrink, and it becomes harder for blood to get through
- Hyperthyroidism: increase of hormones and the metabolism, which causes the heart to pump faster
Other causes may include:
- Diseases of the endocrine system (like Cushing's disease)
- Disorders of the central nervous system
Many cats with hypertension have no signs at all. In cats that do show signs, the most common one is eye abnormalities:
- Enlarged pupils
- Blood in the eye
- Sudden blindness
- Lack of energy
- Blood clots
- Rapid heart rate
If the underlying cause is kidney disease or hyperthyroidism, there will be additional signs:
- Increased thirst and urination
- Vomiting and weight loss
- Dull, un-groomed hair
To properly diagnose your cat with hypertension, your veterinarian may perform the following:
- Physical examination: eyes, brain, heart, and kidneys
- Doppler flow detector: repeated measurement of blood pressure
- Blood tests: to check for underlying causes
- X-rays and ultrasounds: to check underlying causes
Most veterinarians will recommend the following treatments for cats with hypertension:
- Medication to lower blood pressure
- Treatment of the underlying disease
- Reduction of weight and sodium
If your cat is older, or has kidney or thyroid problems, you should have your veterinarian regularly test its blood pressure.
Hyperthyroidism is usually curable, but the prognosis depends on the severity of the underlying cause.
If the cat became blind, it may regain its vision if caught early enough.
Medically Reviewed by Sara Ochoa, DVM