Canine Heartworm

Heartworms are a very common parasite affecting our dogs, in fact in many parts of the country the disease has reached endemic proportions. The disease itself, if left undetected and untreated can often be fatal, and the sad truth is that screening and prevention is so easy and inexpensive. The disease is caused by a worm which migrates to and invades the heart and the vessels around the heart and lungs. The parasite is introduced into the dog's bloodstream via the bite of an infected mosquito which injects the infant form of the heartworm, called microfilaria. It is because of this mosquito transmission that the disease is so prevalent in parts of the world where mosquitoes are such a problem.

Early heartworm disease can often mimic many other conditions. Early signs may simply be a soft cough and a decrease in general energy, but as the disease progresses affected dogs become very sick exhibiting signs of severe lethargy, anorexia, weight loss, and respiratory problems. In advanced cases, patients can suffer from congestive heart failure and even kidney failure.

Since these signs can also be seen with other serious diseases and conditions, it is important to get an accurate diagnosis before instituting any treatment. An accurate diagnosis is made with a special blood test to determine if the signs we are seeing are caused by heartworms, as well as chest radiographs to evaluate specific changes attributed to heartworm infestation. A general blood panel and urinalysis will also be necessary to evaluate the dog's general health and organ function prior to treatment, and an ultrasound study may be needed to assess any potential damage to the heart muscle.

Once an accurate diagnosis is made, a medication is available that can eradicate the worms from the dog's heart and major vessels in the lungs. But, it is important to know that the damage these worms have caused may be irreversible. Treatment is serious, and dogs will usually need to be hospitalized for several days during the treatment process. Even after hospitalization and treatment, it will be necessary to dramatically decrease the patient's exercise for a while.

Since 100% of unprotected dogs living in heartworm endemic areas are highly susceptible to this deadly disease, I highly recommend you talk to your veterinarian about the easy ways to prevent it. Show your dog how much you love it, and ask your veterinarian if heartworm preventative should be part of your pet's routine health care.