High blood pressure, or hypertension, is a condition that might not get as much attention in cats as it should. Cat owners need to be aware of this silent condition, as it can lead to serious health issues if left untreated.
What is Feline Hypertension?
Hypertension in cats, like in humans, is a condition in which the blood pressure in the arteries is persistently high. This can seriously affect your cat’s health, particularly vital organs like the heart, brain, eyes, and kidneys. The condition is much more common in older cats.
Why It Happens
There are two main types of hypertension in cats: primary (or idiopathic) hypertension, where there's no identifiable underlying cause, and secondary hypertension, which occurs as a result of other health issues, such as kidney disease, hyperthyroidism, or diabetes. Interestingly, about 13%-20% of feline hypertension cases are idiopathic.
Spotting the Signs
Cats are masters of disguise when it comes to hiding illness, but there are some signs you might notice:
- Sudden changes in vision, including blindness or dilated pupils
- Altered behaviour or activity levels
- Increased drinking and urination
- Signs of kidney issues like weight loss or vomiting
High blood pressure is often silent, producing no external clinical signs. We routinely check blood pressure in our senior wellness checks (cats over ten years of age) and in cats with predisposing conditions such as kidney disease.
How is Blood Pressure Measured in Cats?
Measuring blood pressure in cats involves a process similar to the method used in humans, but it's tailored to be cat-friendly and account for their smaller size. Here's a general overview of how we typically measure a cat's blood pressure:
1. Preparation and Calming the Cat
Cats can easily get stressed, especially in a veterinary clinic, and stress can temporarily increase blood pressure. So, it's crucial to keep the cat as calm as possible. This might involve:
- Providing a quiet and calm environment.
- Allowing the cat to acclimatise to the surroundings.
- Using gentle handling techniques.
- Sometimes, we might even wait for a while after the cat has arrived before starting the measurement just to let the cat settle down
Very nervous cats may benefit from a low dose of gabapentin before the visit to relieve anxiety.
2. Positioning
The cat is usually placed in a comfortable, seated or lying position on the exam table or the owner's lap.
3. Equipment
We use a special cuff, similar to the one used for humans but much smaller, designed to fit a cat’s leg or tail. A device called a Doppler flow unit might also be used. This device emits ultrasound waves to detect blood flow and produces audible sounds so we can hear the pulse and read the blood pressure. Alternatively, we might use a specialised computer-assisted automated machine called a "high definition oscillometric" (HDO) device.
4. Cuff Placement
The cuff is wrapped snugly around the cat’s paw or tail. The cuff must be the correct size—too large or too small could give inaccurate readings.
5. Taking the Measurement
We then inflate the cuff and then slowly deflate it while listening to the blood flow sounds through the Doppler device or monitoring the readings on an automatic device—the pressure at which the blood flow sound starts (systolic pressure) is noted. The process is repeated several times to get an average reading, ensuring accuracy.
6. Interpretation
We then interpret the readings based on standard values for cats. We'll consider factors like the cat's age, breed, and underlying health conditions, especially kidney issues.
Please view the following video to observe a blood pressure reading with the Doppler device:
Please view the following video to observe a blood pressure reading with the HDO device:
It's worth noting that a single high reading doesn't necessarily mean a cat has hypertension. Cats might have elevated blood pressure due to the stress of the vet visit (often referred to as "white coat syndrome"). Therefore, we usually look for consistently high readings over multiple visits or an exceptionally high reading along with symptoms or evidence of organ damage (for example, issues on examination of the back of the eye or retina) before diagnosing hypertension.
Treatment Options for High Blood Pressure
Management of feline hypertension often involves medication, like amlodipine or telmisartan, to help lower blood pressure. In cases of secondary hypertension, treating the underlying condition is also crucial. Regular monitoring and follow-up visits are necessary to ensure the treatment is effective and to adjust as needed.
Living with Hypertension
If your cat has been diagnosed with hypertension, regular monitoring and medication will likely become part of your routine. However, with the proper care and treatment, most cats with high blood pressure continue to live happy and healthy lives.
In summary, feline hypertension is a serious but manageable condition. Regular vet visits, attentive observation at home, and proper treatment can significantly improve your cat's quality of life. If you notice any unusual symptoms or changes in your cat’s behaviour, don’t hesitate to contact us. Early intervention is the key to managing this condition and helping your feline friend lead a long and healthy life.