High blood pressure in cats, also known as systemic hypertension, is a serious condition that can lead to life-threatening health complications. Cats with high blood pressure often suffer from heart and kidney disease, so it's important to address the issue as soon as possible. Additionally, cats with high blood pressure usually have other health issues that need to be addressed too. Here are some ways to deal with your cats' high blood pressure so they can live a long, healthy life.
What is systemic hypertension in cats?
Hypertension is the medical term for high blood pressure. Hypertension in cats is when the systolic blood pressure is above 160 mmHg. Normal blood pressure in cats is <140 mmHg. There are 3 types of hypertension in cats:
- Situational hypertension - high blood pressure noticed in a clinical setting, such as "white coat syndrome". Typically the blood pressure values are less than 140-160 mmHg.
- Primary hypertension - Also known as idiopathic hypertension. Primary hypertension is uncommon in cats and dogs.
- Secondary hypertension - Secondary causes of high blood pressure in cats and dogs account for 80% of all cases. Secondary hypertension occurs as a result of a current disease process.
Blood pressure in cats is managed by many, complex interactions between the nervous system, heart, and kidneys. Systemic hypertension has the potential to cause a variety of adverse effects, with the brain, eyes, kidneys, and heart being particularly susceptible.
What are the causes of high blood pressure in cats?
Chronic kidney disease and hyperthyroidism are the most common underlying causes of hypertension, followed by diabetes mellitus, hyperaldosteronism, and hyperadrenocorticism. Secondary hypertension is more frequent than primary hypertension, resulting in a higher incidence of hypertension in older cats.
What are the clinical symptoms of high blood pressure in cats?
In most cases, clinical signs are a reflection of the underlying disease. Abnormalities of the eyes, the nervous system, and the heart are common. Sudden blindness with dilated pupils can be a common association with high blood pressure in cats. Other neurological signs include high-pitched vocalization, altered behavior, seizures, paralysis of the hind end, and paraplegia. The clinical signs are also related to which organ is being affected. Heart failure due to high blood pressure leads to jugular thromboembolism if the systolic pressure is high in the left atrium.
How high is too high?
For high blood pressure in cats, anything over 180 mmHg(systolic) is considered severely high. Because hypertension compromises the function of many organs, it's very important for your cat to receive treatment. However, high blood pressure puts cats at risk for life-threatening conditions like thromboembolism.
How high is high blood pressure in cats diagnosed?
Diagnosis of high blood pressure in cats begins with a complete physical examination by your veterinarian. A number of changes can be observed during the course of high blood pressure, so it's important to keep an eye out for any subtle changes your cat may exhibit. Blood work will be needed to measure your cat's kidney function, electrolytes, blood glucose, and thyroid hormone levels.
One of the most accurate tools veterinarians use to measure blood pressure in cats is the Doppler method. The Doppler technique, which uses ultrasound to measure blood flow through a vein, is one of the most common methods for determining blood pressure in cats. The Doppler measurement only reveals the systolic blood pressure and is unable to measure diastolic blood pressure.
How high is high blood pressure in cats treated?
The best option for high blood pressure in cats is to address the underlying cause. Treatment should begin as soon as high blood pressure is diagnosed. Your veterinarian will recommend certain medications to keep high blood pressure under control and reduce the risk of cardiovascular damage. Common classifications of medications used to treat high blood pressure include:
- Calcium channel blockers - Amlodipine is the most commonly used calcium channel blocker and is the first drug of choice for treating cats with hypertension.
- Beta-blockers - Despite being largely replaced by calcium channel blockers, beta-blockers may still have a role to play in treating hypertension and tachycardia associated with hyperthyroidism. Common examples include atenolol and propranolol.
- ACE inhibitors - As a second-line medication for cats, ACE inhibitors can be used in conjunction with amlodipine.
What is the prognosis for cats diagnosed with high blood pressure?
There is a high degree of variability in the prognosis and it depends on a number of factors, including hypertension severity, underlying disease status, and response to antihypertensive therapy.
High blood pressure in cats is a serious condition that can often lead to other health problems. If your cat has high blood pressure, it's important to get them treated as soon as possible. Treatment usually involves medications to keep high blood pressure under control. With proper treatment, most cats with high blood pressure can live a long, healthy life.