Heartworm For Dogs, Four Stages Of Disease

Heartworm for dogs can be very severe, even fatal. If it has been diagnosed in your dog, it goes without saying that it is a very worrying time.

Your veterinary surgeon will assess your pet to decide which of the four categories (or stages) of the disease he is in before deciding on the best course of heartworm treatment for dogs available.

Many factors are taken into consideration during assessment of of the problem in dogs. The most basic being the size, age and weight of the dog, pre-existing health problems and the severity of the infection with adult worms.

Some vets now have access to computerised aids to diagnosis into which all these factors can be fed and a result will be produced for the vet to act upon.

Heart worm is classified as follows in dogs:-

Heartworm for dogsClass 1
A dog categorised as class one is at the lowest risk. Usually this will be a younger dog who is normally healthy, has normal blood test results and is not exhibiting any symptoms of the disease although minimal disease presence has been seen on x-ray plates. A dog in class one will probably only cough very rarely, if at all and may only show minor signs of fatigue even after quite strenuous exercise.

Class 2
A dog categorised as class two has the signs of a dog in class 1 and will only exhibit signs of fatigue with exertion however, there is some coughing and the radiographs show clear evidence that heart disease is present. In addition the blood tests will show the first signs of anaemia, possibly the first signs of liver and/or kidney damage, and urine testing will show the first signs of protein in the urine.

Class 3
A dog categorised as class three is severely affected. By now, the dog is losing weight, has a cough and some difficulties with breathing. Radiographs reveal obvious damage to blood vessels and blood tests show more marked anaemia and very likely kidney and/or liver damage. In addition urine tests reveal significant amounts of protein in the urine.

Class 4
A dog categorised as class four is very severely affected indeed and is on the point of collapse or actually collapsing in toxic shock. This is the most severe stage and is sometimes referred to as Caval Syndrome where there are so many heartworms in the right side of the dog’s heart that it cannot function.

A dog in this class could only be saved by surgery to remove the adult worms from the jugular vein. Even then, if the dog recovers from the surgery, no further treatment can be carried out unless the dog recovers enough to be categorised as class three or below. Sadly many canine patients who come into the veterinary practice presenting with Caval Syndrome still die despite the very best efforts of everyone concerned. You can see a dog undergoing successful surgery for this stage of the disease on my article on heartworm treatment for dogs.

Heartworm for dogs is heartbreaking for owners and devastating for dogs, please see our articles and information about prevention and treatment.
[ad#Heartworm large ad each post]

You might like to read this comment from Carley’s owner after successful treatment:-

Carley is 100% HW free. She was Class 3-4, so the vet said even if we treated her it would be 50/50. But she did very well, despite getting mange right after her second round. We have spent about $1400 on all of this treatment, but she is soooo worth it. Sometime you can go to shelters (or petition the vet) who will treat at a discounted rate, or make payment plans.


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>