First of all, this starts my series of blogs under the grouping “What I Learned At My Continuing Education” section. The goal of this education was to learn about any new research or changes in veterinary medicine, especially those changes that will help save or prolong lives as we practice and recommend better medicine.
Secondly, I never realized heartworm disease in cats is as common or as dangerous. Quite frankly, no one did. For years, everyone has been saying that cats can get heartworms, but they aren’t common. However, new research is changing the way we think about heartworm disease in cats, and the research shows that prevention is just as important for cats as it is for dogs. Let me explain.
In dogs we typically see problems with living heartworms. In cats, we see problems with dying heartworms. What makes this even worse for cats is heartworms don’t live very long in cats. Within 70-100 days (barely more than 2-3 months) after infection, heartworms are already in the arteries of the cat’s airways and are dying. When they die the blood flow pushes them to the edge of the lungs and they lodge in a very tiny vessel. This keeps the blood from reaching that part of the lung and creates a huge inflammatory response and dying tissue.
What does all this mean anyway? Well, we are realizing “asthmatic cats” may actually have dying heartworms causing airway and vessel inflammation usually thought to be allergies. As many as 20% of infected cats will die suddenly, with no warning they even have heartworms. Even cats who don’t die from the heartworms have airway, vessel, and lung disease that is irreversible after these worms die in the lung vessels. Additionally, studies are showing that previous tests to find cats with heartworms are poorly reflective of how common of a problem they are in the general population.
All this adds up to indicate that heartworms in cats are as common and serious as heartworms in dogs.
Its a simple message really – if we recommend heartworm prevention for dogs, we recommend prevention for cats.
And before you take a sigh of relief – indoor cats are not safe. There is too much information on infected and diseased indoor cats to ignore it.
Fortunately, prevention is simple – Revolution can take care of heartworm, flea, intestinal parasite, ear mite, and some tick prevention. Given monthly, that is a great combination and spectrum of treatments. I know its a hard pill to swallow putting your cats on year round prevention, and I know it isn’t cheap. However, I am convinced that the single most important thing you can do for your cat aside from yearly checkups is regular monthly heartworm prevention.
I’ve got more blog posts about my continuing education, but this just couldn’t wait any longer. This really does change everything for cats.
– Doc Cleland