Let’s get one thing straight: Heartworm in dogs (cats) should only be treated by a qualified veterinarian. As you have already gathered from the last three TPC columns, the heartworm ailment is quite complicated; so too is the treatment of the disease. For one thing, the symptoms might lead one to follow a therapeutic path that does not address the underlying cause of the disease. For example, I had mentioned that a soft yet deep cough is often associated with this malady. Now, if one were to treat the animal for coughing, no great progress would be made, since the real culprit is the heartworm, and no amount of cough syrup will injure this beast. The real moral of the story is not to let a quack treat a dog/cat that might be infected with heartworm.
Treatment
You remember that, over the last three weeks, I have been emphasising the insidious nature of the ailment.
It creeps up on the poor animal. Symptoms only show themselves when the heart and other organ systems cannot cope with the pressures on the normal function of the animal’s body. All the time, during the period between the acquisition of the infection and the exhibition of the symptoms, the animal was compensating. A heart, whose chambers are compromised by the worms contained therein, must out of necessity pump faster since less blood volume per heart contraction is being delivered to the organs. As the disease progresses the organs become more and more starved of blood and as a result the organ functions begin to deteriorate to the point of total collapse.
The first step in the treatment of heartworm will therefore be an evaluation of the dog’s physical condition. Only a veterinarian can competently do this. In all likelihood, this would mean stabilizing the heart failure and the liver and kidney insufficiencies. In other words, long before the actual, specific treatment begins we have got to get the dog’s health status to a level which would allow him to cope with the treatment – and what a treatment it is!
At present, the drug of choice to kill the adult heartworm is an arsenic compound. Your veterinarian will be injecting arsenic into the dog’s muscle or vein. So you can see the potential danger in the administration of this therapy, if the dog’s health status has not been propped up sufficiently. Worse, this injection of the arsenic salt into the bloodstream has to be done four times in 36 hours (morning – evening – next morning – evening). If, for whatever reason during the process of an intra-venous injection, the needle slips out of the vein, or if some of the arsenic leaks out of the vein, then a most painful swelling develops. If we use the intra-muscular route, then only certain muscles can be used – and these are not the huge muscle packets in the hind leg.
Let’s take for granted that your competent veterinarian has carried out the therapy efficiently.
The spaghetti-like worms in the heart are now all dead. The problems are over, you think. Not so! If the dog suddenly exerts itself too much and one of the dead worms disassociates itself from the bundle and gets into the blood stream (pulmonary circulation) and ends up as an embolus in the lung, the animal might just keel over and be instantaneously dead.
This means that after the heartworms have been killed the animal must be kept quiet (no strenuous exercise, no sudden movements, no springing over fences, no chasing of cats, no fighting with other dogs, no mating, etc). The dead heartworms will disintegrate and be absorbed slowly over the period of about two months by the body.
The heartworm problem is still not over. Don’t forget that we still have the microfilariae (immature stages of the heartworm) in the circulating blood. They have to be killed too, so that they won’t grow into adults which can reproduce.
How to kill the microfilariae and how to control the heartworm scourge is next week’s topic.
Please implement disease preventative measures (vaccinations, routine dewormings, monthly anti-heartworm medication, etc) and adopt-a-pet from the GSPCA’s Animal Clinic and Shelter at Robb Street and Orange Walk, if you have the wherewithal to care well for the animals. Do not stray your unwanted pets, take them to the GSPCA Clinic and Shelter instead. If you see anyone being cruel to an animal, get in touch with the Clinic and Shelter by calling 226-4237.
