However, if left untreated, heartworm disease will progress and damage the dog's heart, lungs, liver, and kidneys, eventually causing death.
A complication of heartworm infection, known as caval syndrome, leads to shock-like symptoms and sudden death.
Dogs that have a high number of heartworms often develop symptoms such as pronounced and persistent coughing, difficulty breathing, and exercise intolerance. In more severe cases, dogs may also experience fainting or collapse, pale mucous membranes, weakness, elevated heart rate (tachycardia) and severe lethargy.
Adult heartworms have been known to survive inside a dog's heart for 7 years before they die on their own. Your dog does not spit them up, poop them out, or dissolve them on his own. The adult worms will live a long, productive life inside your dog's heart wreaking havoc on his heart and lungs.
As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen. Dogs with large numbers of heartworms can develop a sudden blockages of blood flow within the heart leading to a life-threatening form of cardiovascular collapse.
Class 3: More severe symptoms such as a sickly appearance, a persistent cough, and tiredness after mild activity. Trouble breathing and signs of heart failure are common. For class 2 and 3 heartworm disease, heart and lung changes are usually seen on chest x-rays.
How Long Can a Dog Live Without Heartworm Treatment? A dog can live at least six to seven months from the date of infection.
Stage 4. There is a large mass of worms which physically blocks the blood flowing back to the heart. This stage is life-threatening and requires quick surgical removal of the heartworms. However, surgery is risky and even with surgery, most dogs in this stage die.
Signs of heartworm disease may include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss. As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen.
Discussion. Hemoptysis (expectoration or coughing up of blood) has been reported as a consequence of severe heartworm infection in dogs,2-6 although it remains a relatively uncommon finding. Even fewer reports exist of dogs coughing up or vomiting up adult heartworms.
Stage 4 – Heartworms have caused severe damage to the animals heart, lungs, liver, and kidneys. In this stage, Caval syndrome is likely. Caval syndrome is when there is such a large amount of worms blocking blood flow to the heart that it creates a sudden life-threatening problem in need of quick surgical intervention.
Six months after they bite your dog and inject those larval microfilariae heartworms into your dogs, it takes that six months for them to develop into that adult worm. So generally, it's anywhere from six to 12 months after they've been bitten; you may start noticing signs in your pet.
After treatment, the adult worms die and are carried by the blood to the lungs where they lodge in small blood vessels. There they decompose and are absorbed by the body over a period of several months.
The adult worms die in a few days and start to decompose. As they break up, they are carried to the lungs where they lodge in the small blood vessels and are eventually reabsorbed by the body.
Also, as the heartworms block vessels, the areas around these vessels will see fluid build-up, making it even harder for your dog to breathe and get oxygen, causing him to take more shallow, rapid breaths.
With heartworm disease treatment can be extremely difficult even for the young otherwise healthy dogs but our senior dogs can see more severe side effects and death if progressed disease is present. Know that 1 in 10 dogs will develop some form of heart disease as they age.
Speak with the shelter staff to determine what testing has been performed and the results. If there has been no formal testing outside a general heartworm test at the shelter, make sure a heartworm test is done at the first visit to your veterinarian. The good news is that your dog can be cured of heartworm disease.
Average Cost of Treatment. The average cost of heartworm treatment for dogs is often around $1,000. However, it can range from $500 to $1,100 or even more depending mainly on the size of your dog, veterinary bills, and the stage of the disease.
Class 3 Heartworm Infection
During this stage, a dog may have a cough that is very severe. They may also have difficulty breathing and make strange sounds when they breathe. Much more extreme lethargy is likely at this stage. Having a pot belly, weight loss, and a reduced appetite occurs as the condition progresses.
“Goose Honk” Cough
The first and most obvious symptom of heartworm in dogs is the persistent cough, which is often likened to the sound of a goose hoking. This goose honk cough occurs whether the dog has been active or not, but it is more common after a dog has just exerted himself in some way.
They can be controlled naturally with citrus oils, cedar oils, and diatomaceous earth. Dogs needing conventional treatment may benefit from herbs such as milk thistle and homeopathics such as berberis; these minimize toxicity from the medications and dying heartworms.
If owners can't afford treatment at the time of diagnosis, Dr. Herrin recommended delaying melarsomine therapy but still initiating treatment with both a preventive and doxycycline. This will prevent further infection and remove the dog as a heartworm reservoir.
Most dogs can be safely leash-walked during the treatment recovery period and providing appropriate chew toys can help relieve some of that stored up physical energy.
How can my veterinarian tell if my dog has heartworm disease? After examining your pet your veterinarian may find symptoms that are suggestive of heartworm disease. Listening to the chest with a stethoscope will often reveal abnormal lung and heart sounds.