Tugging at the Heartstrings: feline cardiac disease
Feline cardiac disease can be heartbreaking for many reasons, but most upsetting is that it is so often undetected. For many owners, this leads to the sudden loss of their beloved pet. Cats hide their heart disease so well that many of them show no clinical signs until they are very sick. Some show no symptoms at all and simply perish suddenly, seemingly without cause.
Heart disease in cats is relatively prevalent, occurring in 15 percent of all cats. So why are so many cases going undetected? The answer is complicated, of course, but part of the reason is that in the past, we didn’t have a great way of finding heart disease in the average, healthy-looking cat.
Every year (or every six months, for geriatric cats), your veterinarian listens to your cat’s chest with a stethoscope as part of your cat’s annual (or semi-annual) exam. One of the things she or he is listening for is a heart murmur. A heart murmur is caused by turbulent blood flow in the heart or great vessels of the heart. Anything that causes some obstruction in these structures leads to a “whooshing” sound as blood squeezes through. This is a heart murmur. If your cat has a heart murmur, she is more likely to have heart disease, but it turns out that the presence of a murmur is not all that great of a screening tool. Here’s why: a study of 103 average “healthy” cats performed at Virginia Tech found underlying heart disease in 16 of those cats, but only five of those 16 cats had a murmur.
There is a relatively new blood test, however, that may help veterinarians find sneaky heart disease in healthy-looking cats. It’s called NT-proBNP, and it is a biomarker of cardiac disease. Its production is markedly increased when the heart’s ventricles stretch or undergo stress, so higher levels of BNP could mean the heart is in trouble. Unfortunately, this test is not perfect either, but it is thought that it can catch heart disease in nine out of 10 healthy looking cats.
Regardless of the method of detection, if heart disease is suspected, your cat should have an echocardiogram (or ultrasound of the heart), a diagnostic test that can be covered by your Petplan pet insurance. This test is noninvasive – although your cat’s chest fur may be shaved – and provides an actual image of the heart. Heart size, wall thickness and the ability of the heart to contract and move blood can all be assessed in real time, giving your veterinarian an idea of what is happening in the heart.
Early detection is key in feline cardiac disease. Initiating therapy early can mean a reduction in clinical signs such as thromboembolisms and can delay the onset of congestive heart failure.
At your cat’s next exam, consider asking your veterinarian about the NT-proBNP test. When to run the test is open to debate, but some experts advise running it every two years in cats over the age of one. It could be a life saver for your cat.