We as people, are very used to getting our blood pressure taken. It is done at any and all doctor visits and is considered vital information. Should cats have their blood pressure measured too?
Young cats generally do not have problems with high blood pressure, much like young people. As they age however, high blood pressure can and does occur in cats. It can cause kidney damage, heart damage and blindness in cats.
Most cats don’t get a primary hypertension due to plaque building up in blood vessels and impeding blood flow. They get a secondary hypertension which means that the elevation in blood pressure occurs due to a change in the system that is actually being caused by a different disease. We most commonly see high blood pressure in cats with kidney disease, hyperthyroidism and heart disease.
How do we measure a cat’s blood pressure? We measure blood pressure in cats using either an artery in the back foot or on the underside of the tail base. We shave the hair over the area of the vessel and then we apply a cuff above the vessel. We use an ultrasound crystal to isolate and magnify the blood pressure. We hear the blood pressure through a machine connected to the crystal. Once the blood pressure is able to be heard, we inflate the cuff tight enough to restrict blood flow and then slowly release it. When the blood pressure is able to be heard again, that is the systolic measurement of the blood pressure. We are only obtain to this measurement in pets so we interpret blood pressure on this value only. We get the spot shaved and the cuff placed and the blood pressure located, and then we take several readings over a few minutes to allow for some reduction of stress.
High blood pressure going through small vessels can cause them to rupture or leak. Many geriatric cats will have small retinal hemorrhages (bleeding from small vessels in the back of the eye) noted during physical examination. These cats definitely need a blood pressure measurement. It generally isn’t something that can be noted by the owner at home unless the cat becomes suddenly blind. Unfortunately, acute blindness is the most common presentation of cats with hypertension. The extremely high blood pressure causes the retina of the eye to detach which leads to blindness. Your cat may suddenly have extremely dilated eyes all the time if this happens. We do have the possibility of regaining vision if we are able to diagnose and lower the blood pressure and reduce inflammation to the back of the eye quickly. High blood pressure can also lead to a stroke in pets.
It is best to measure blood pressure on cats before we have sudden blindness so your veterinarian may recommend this test on a senior cat or a cat with other underlying diseases. High blood pressure can be treated and doesn’t have to lead to more disease.