What Are the Signs of Heartworms in Dogs?

Educating your patient base about the common signs of canine and feline illnesses helps them know when to call your veterinary office with concerns. As you know, heartworm disease is one of the more serious illnesses dogs can face. Use this guide as a resource for educating your pet parents about the signs of heartworms in dogs, and encourage them to contact your practice when they see worrisome symptoms in their furry friends.

Weave’s veterinary software can help your practice streamline communications with pet parents and better serve your patient base.

How is heartworm disease transmitted?

Heartworm disease refers to a parasitic infection that dogs, cats, and other mammals can contract through infected mosquito bites. This disease can cause significant damage to the heart, arteries, and lungs and can impact a dog’s quality of life. Thankfully, it is preventable with year-round heartworm preventive medication, which veterinarians recommend for all dogs.

When an infected mosquito bites a dog, it deposits microfilaria into the dog’s bloodstream. Without preventive medication, these microscopic larvae migrate through the dog’s body, eventually reaching its heart and lungs.

The infective heartworm larvae cannot be detected in the dog’s bloodstream until at least six months after the mosquito bite, which is why testing puppies who are younger than six months is ineffective. This is the amount of time necessary for the larvae to develop into adults, at which point the adult female heartworms reproduce inside the infected animal.

Common signs of heartworms in dogs

Pet owners should be aware of common signs that their dog has contracted heartworm disease. These are a few typical signs of heartworm disease; however, some dogs initially experience no symptoms, which is why annual heartworm testing is an important step in catching and treating this condition early.

Mild, persistent cough

Dogs with heartworm infection often experience a mild cough that may worsen over time. This cough is dry-sounding and typically exercise-induced. It may become more frequent as the disease progresses.

A dry cough is often one of the first signs of heartworms in dogs. Pet owners should pay attention to any ongoing coughing symptoms their dogs experience and talk to their vet as soon as possible.

Exercise intolerance and lethargy

Dogs with heartworm disease might also tire easily after moderate exercise and show signs of exhaustion when engaging in physical activity they previously enjoyed. Lethargy and reluctance to exercise might indicate that the adult heartworms have damaged the dog’s heart, lungs, or blood vessels, impairing the heart’s ability to pump blood and deliver oxygen throughout the body. Dogs with a heartworm infection may not have the physical stamina they used to.

Weight loss and decreased appetite

In the middle stages of heartworm disease, dogs can experience weight loss and reduced appetite. These signs are often subtle but can indicate an ongoing health issue. Any changes to a dog’s appetite should be a topic of conversation with their veterinarian.

Difficulty breathing

Heartworm-associated respiratory disease can lead to breathing difficulties in dogs. This may look like wheezing, rapid breathing, and a labored pulse. Pet owners may notice their dog struggling to catch their breath during sleep or after physical exertion.

Swollen abdomen (ascites)

Advanced heartworm disease can lead to a swollen belly, known as ascites. This indicates a buildup of fluid in the abdomen due to heart failure. A dog may show other signs of discomfort as well, such as stiffness, aggression, whining, or yelping.

Pet owners who notice ascites should take their dog to the vet immediately for treatment. The vet can create a treatment plan to remove the fluid and treat the heartworm disease or symptoms.

Vomiting

Persistent vomiting in dogs should always be evaluated by a veterinarian. A dog who has contracted heartworms may experience nausea or vomiting because their heart is under strain. Frequent vomiting may prevent a dog from gaining the necessary fluids and nutrition, requiring veterinary intervention.

Severe complications that may arise from heartworm disease in dogs

Heartworm disease, while treatable in many cases, is a serious condition that pet owners should not overlook. If left to progress to advanced stages, heartworm infection can lead to severe complications.

Heart failure and caval syndrome

When heartworm disease progresses, it can lead to caval syndrome, a life-threatening form of the heartworm infection characterized by a large mass of heartworms in the right side of the heart and vena cava. This mass obstructs blood flow, leading to cardiovascular collapse.

Signs of heartworm-related heart failure include:

• Pale gums
• Dark urine
• Sudden collapse

These symptoms indicate an emergency that requires immediate veterinary intervention to prevent further complications.

Fluid accumulation and organ damage

Adult heartworm infection can lead to severe organ damage if untreated. It can affect the heart, liver, kidneys, and other major organs, leading to irreversible organ failure.

This is why early detection and management are critical for a dog’s long-term health. Many vets recommend yearly testing, as breakthrough cases can occur even for dogs on a year-round prevention program. Annual testing allows vets to catch this potentially fatal disease before it has time to cause irreversible damage.

How heartworm disease is diagnosed

When pet owners notice signs of heartworms in dogs, they should go to the vet as soon as possible for heartworm testing. This condition can be diagnosed through antigen testing, bloodwork, X-rays, and ultrasounds.

Routine testing requires a small blood sample. A lab test can detect the presence of heartworm proteins in the blood, providing fast results.

If a dog shows symptoms of heartworm disease and the blood test comes back negative, the vet may perform other tests to pinpoint the cause.

Heartworm prevention and communication

Starting heartworm prevention early in dogs and continuing it throughout their lifespan is an important step in protecting animals against this life-threatening condition.

Heartworm preventives work by eliminating heartworm larvae before they can grow into adults. There are several medications approved to prevent heartworm disease: pills, topical medication, and injections. Pills and topical products must be administered on a monthly basis, while injectables last for up to six months.

Veterinarians prescribe heartworm medication approved by the FDA after testing dogs for heartworm disease. The dog will then be tested annually to renew the prescription. If a dog tests positive for heartworms, the preventive will not work, and the vet will recommend heartworm treatment instead.

While heartworm medicine is highly effective for preventing heartworm disease in dogs, it must be given correctly to be successful. Even one missed dose can leave dogs vulnerable to infection.

Weave helps vets improve patient education and communication

Understanding the signs of heartworms in dogs is an important step in recognizing the early stages of this disease and seeking treatment. Veterinarians and pet owners must work together to identify heartworm symptoms and treat them early.

Weave helps veterinarians stay in communication with pet parents through a range of user-friendly features. These tools can help vets educate patients on the signs of heartworm disease, respond to patient queries, and schedule fast appointments when worrisome symptoms are detected.

• Appointment reminders prevent no-shows by automatically reminding pet parents of appointments a certain amount of time beforehand, such as one week, one day, and the day of.
• Online scheduling allows pet parents to schedule appointments at a time convenient for them or find the next available appointment time when they need a prompt visit.
• Digital forms save time in the waiting room by allowing pet parents to complete intake forms in advance of their appointments. Vets can review the forms before the dog’s arrival and be ready to start the exam immediately.

Final thoughts

Recognizing the signs of heartworms in dogs is key to treating this illness before it has time to seriously impact a dog’s health. Early detection saves lives and strengthens the trust between practices and their clients.

Weave helps vets streamline communication for better patient outcomes. Request a demo to learn how Weave can aid your vet practice communications.

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