Biology Reference
In-Depth Information
check for it. Measuring blood pressure in cats is now becoming more
routine because veterinarians have fairly reliable equipment.
In humans both systolic and diastolic measurements are used to
evaluate blood pressure.
Systole
is the highest blood pressure and occurs
when the heart contracts and pumps blood.
Diastole
is the lowest pres-
sure and occurs when the heart relaxes and fills with blood. Systolic val-
ues are considered the most sensitive indicator of feline hypertension,
and values over 180 mm Hg are considered too high.
Hypertension is usually found in older cats who are also affected
with kidney disease and/or hyperthyroidism, but it can also be a pri-
mary disease. If the heart sustains long periods of high blood pressure,
it can weaken. Hyperthyroidism can lead to overstimulation of the
heart muscle, which also wears the muscle out prematurely and leads to
failure.
To control blood pressure in cats, the underlying disease must first
be controlled. If no underlying disease is found, drugs are available to
control blood pressure. Lower sodium diets are also useful.
FELINE HEARTWORM DISEASE
If you have a dog, you may be familiar with heartworm disease. The
heartworm parasite
Dirofilaria immitis
is transmitted by mosquito bites,
which inject the immature stage of the worm into an animal's blood.
These larvae develop into adult worms that like to live in the heart or
pulmonary blood vessels. Heartworm disease can cause breathing prob-
lems and damage to the heart.
Cats have natural resistance to heartworms, but they can still
become infected.There is a higher risk of infection in areas where there
are more mosquitoes carrying heartworm larvae. With no exposure to
infected mosquitoes, cats cannot get heartworm.
Preventive medication is available to protect cats who are at risk for
heartworms.Ask your veterinarian about the risk of heartworm in your
area, and then decide if preventive care is needed.
Diagnosing Heartworms
Heartworms should be considered as a possible diagnosis for cats who
have signs of heart disease, vomiting or asthma and live in a high-risk
area where mosquitoes are present. Blood tests that look for antigens to
the parasite and antibodies the cat produces against the parasite are use-
ful in making a diagnosis. Heartworms can be observed on an ultra-
sound of the heart.
