Canine Heartworm Life Cycle

Diagnosis

Diagnosis of heartworm disease is made by finding the microfilaria in a blood specimen from the infected pet. In certain instances (especially in the cat and occasionally the dog) there will be no microfilaria in the circulation. This occurs when the host animal: 1) is able to destroy the microfilaria, 2) when there is a very small number of microfilaria present and they are not present in the specimen of blood being examined, 3) when the adult population is made up entirely of the same sex, or 4) when the microfilaria have temporarily sequestered themselves somewhere out of the main circulation. At these times a test is done to identify a protein substance that is secreted from the outside of the female adult worm (a heartworm antigen). Chest radiographs can help diagnose heartworms because of the changes that occur to the right side of the heart and to the vessels in the lungs. Ultrasound examination of the heart can often identify the adult worms in the heart. The largest majority of canine heartworm cases are found by examination of the blood -- looking for the microfilaria and/or for the heartworm anitgen.

My Dog Has Heartworms, What Happens Now?

Please don't despair. The majority of heartworm cases, especially if diagnosed early, can be successfully treated with little chance of permanent disability. However, further diagnostic procedures should be performed before treatment is started. Chest radiographs (X-rays) should be made to assess the severity of heart and/or lung changes that have occurred. Blood chemistries and blood count as well as urinalysis are recommended to assess damage to any other organ system.

Canine Heartworm Disease | Canine Heartworm Lifecycle | Canine Heartworm Treatment
Feline Hearworm Disease | Feline Heartworm Lifecycle
Heartworms in the USA | Preventative Comparisons