This disease in cats is primarily a disease of the lungs. In cats, it is a more acute disease, not a slow progressive disease that takes two or three years to kill. It is rare for a cat to go into congestive heart failure from heartworm disease. In its most violent form no symptoms are noticed before the cat is mysteriously found dead. Not all cats show all these symptoms.
Some cats show no symptoms at all.
In fact we now know that some of the cases we have diagnosed in the past as chronic bronchitis and asthma were in fact the cat form of heartworm disease. A feline heartworm test is now part of my standard workup for cats showing these symptoms. Now that we know what to look for we are finding more cases of heartworms in cats. I have found and treated a number of cases in my practice here in Dutchess county. Since heartworm disease is so common in dogs in our county it is easy to see why protecting your cat is so important.