Hypertension in Cats

Blood pressure measurements are composed of two different numbers. The first value, which is the higher of the two numbers, is the amount of pressure that exists in the arteries and is referred to as systolic pressure. The lower number is the measurement of the rest time between heartbeats and is called diastolic pressure. If systolic pressure is gauged at 160 or higher, hypertension is present. Gender and breed have no significant relation to cases of high blood pressure, but old age can contribute to the problem. Hypertension can usually be managed with prompt veterinary attention.

The rate at which a cat’s heart beats combined with the condition of the walls of the arteries determine how much pressure is in the circulatory system. This pressure is commonly monitored as part of regular health checks, as it often points to other problems within the body. When blood pressure is abnormally high, the cat is said to have hypertension. This issue is common in cats, and it can be quite serious. Hypertension can cause other body parts to begin to malfunction.

Often, symptoms that relate to the underlying cause of the high blood pressure will accompany the basic signs of hypertension. Effects on the brain and eyes may be sudden and indicate severe damage has taken place. Symptoms to watch for include:

• Change in appetite
• Weight loss
• Vomiting
• Polyuria (frequent urination)
• Polydipsia (increased thirst)
• Dull coat
• Lethargy
• Labored breathing
• Sudden blindness
• Retinal hemorrhaging
• Confusion
• Odd behavior
• Stumbling
• Seizures
• Coma

In most cases of high blood pressure, there is a health issue somewhere in the body creating the increase in pressure. Over 60 percent of cats who experienced kidney failure, and over 90 percent of cats with hyperthyroidism also had hypertension. In rare instances, high blood pressure may have no cause. Those occurrences are referred to as “essential hypertension”. Possible causes of hypertension in cats are listed as follows:

• Heart disease
• Kidney disease
• Hyperthyroidism
• Diabetes
• Benign or malignant tumor on an endocrine gland
• Medication prescriptions
• Obesity

A high blood pressure measurement may be found during a routine veterinary visit. If you have brought your cat to a veterinary clinic or animal hospital due to alarming symptoms, be sure to provide the cat’s full medical history. A complete physical examination will be performed on the cat. The cat’s blood pressure can be measured by use of a special cuff on the leg or tail. It is a quick and painless procedure, but some cats still require calming and multiple readings to produce a true blood pressure reading. 

Full blood work will be run including a complete blood count and a biochemical profile. These will be used to look for a potential cause of high blood pressure. An ocular exam may reveal changes to the blood vessels at the back of the eye. Ocular changes are usually present in both eyes. Hypertension can interfere with kidney function, eyesight, cardiac function and the central nervous system. An X-ray may reveal thickened heart muscles due to over-pumping blood. Both the eyes and the brain may bleed in extreme cases.

To properly treat hypertension, the rise in blood pressure itself will have to be addressed, along with the underlying cause of the issue. If damage has occurred from high blood pressure, certain health problems that have developed secondary to hypertension may also need treatment. 

Medication 

Using medication has been shown to be very effective at lowering a cat’s blood pressure for a long period of time. Amlodipine (a calcium channel blocker) and benazepril (an angiotensin-converting enzyme inhibitor) may be used separately or combined to treat hypertension. These medications work by both relaxing and dilating the blood vessels. It may take time and some dosage experimenting to establish an effective prescription for your cat’s specific needs. Hypertension can be controlled, and in some cases reversed, by these prescription medications.

Specialized Diet 

Depending on the underlying health problem that has caused hypertension, your veterinarian may create a diet tailored to your cat’s circumstance. This diet must be species appropriate and may be geared at helping the cat to lose weight.

If hypertension is identified before any severe organ damage has taken place, it is very treatable. The exact prognosis will vary depending on the primary health problem within the cat. Most organ and ocular damage that occurs will be permanent, making early diagnosis key whenever possible. You will be required to bring your cat to follow-up appointments with the veterinarian to assess how the cat is responding to its medication.

Promote regular exercise through play to help your cat stay slim. Stick to any diets that have been administered by your veterinarian to prevent further issues from developing. Many notice a greatly improved morale in their cat after it has successfully undergone treatment for high blood pressure. If your cat is over seven years of age, getting its blood pressure checked as part of a regular examination should be completed at least twice a year. This can also help identify other health issues before they become a threat to your cat.