Blood pressure measurements have been a standard in human medicine for many years, and due to recent advances in blood pressure measurements for our pets, it may not be the first thing done, but it is becoming more common for routine, annual, pet health checkups. As a result, hypertension (i.e., high blood pressure) is being diagnosed more frequently.
Your pet's blood pressure may be measured using a Doppler flow detection system or oscillometic method, both are similar techniques to those done in your doctor's office. Initial readings may be high due to stress and anxiety in unfamiliar surroundings - affectionately termed "white coat hypertension."
Hypertension in our pets usually indicates: kidney or heart disease, Cushing's disease, anemia, obesity, diabetes or feline hyperthyroidism. Blood and urine tests help determine the underlying cause of hypertension but there are a growing number of cases, particularly in cats, where no underlying cause is found.
Veterinarian Dr. Anthony Carr stresses that blood pressure should be checked routinely on all geriatric cats as well as dogs and cats at risk for hypertension due to a previously diagnosed disease such as kidney failure.
"Some patients will show obvious signs of hypertension, but often hypertension is silent," said Carr, associate professor at the Western College of Veterinary Medicine, University of Saskatchewan in Canada.
Hypertension alone damages vital organs including the eye, brain, heart and kidney. Owners with pets experiencing hypertension may report sudden loss of vision and/or widely dilated pupils. Possible neurological signs of hypertension may include circling, a tilt of the head or seizures. Signs associated with an underlying disease like heart and kidney disease are subtler and may include lethargy, depression, difficulty breathing, increased thirst and urination, weight loss, and increased or decreased appetite. Bleeding from the nose may also occur.
Dr. Christine Wilford, a private-practice veterinarian at Cat's Exclusive Veterinary Hospital in Shoreline, Wash., sees hypertension in almost one quarter of the geriatric cats she treats. "I'd say maybe 20-25 percent of those kitties over 13 years of age, those with unexplained dilute urine, renal failure and hyperthyroidism have mild to severe hypertension when I determine their pressures," she said.
One such case from Wilford's practice was Samantha, a 15-year-old female spayed grey tabby cat who was brought in by her owner because she was howling. On a hunch, Wilford measured her blood pressure, and as suspected, Samantha's blood pressure was high. She was sent home on amlodipine, an antihypertensive medication commonly used for cats. Samantha's owner reported that after taking amlodipine, not only had Samantha stopped howling, but she was playing like a kitten again. Her blood pressure was normal four days later.
Your pet may be referred to a veterinary ophthalmologist or cardiologist if diagnosed with hypertension. In addition to treating the underlying cause, veterinarians have an array of new antihypertensive medications to control hypertension. Special diets may be required and treats high in salt should be avoided. As in man, blood pressure will need to be monitored to tailor the medications to the individual pet and lifestyle is a factor.
Prognosis is good for treating hypertension if caught early and pets that experience a loss of vision may have their vision return. Occasionally, high blood pressure will return to normal if the underlying disease is successfully treated and then use of antihypertensive medications may no longer be needed.