Myocarditis In Dogs: Symptoms, Causes, & Treatments

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Myocarditis in dogs, also known as heart inflammation, is a disease caused by swelling of the heart’s muscular wall, called the myocardium. The swelling usually results from a viral, bacterial, fungal, or other kind of infection, but it can also be caused by injury, mineral deficiency, or exposure to toxins.

Because the heart is so important to many of dogs’ bodily functions, this condition can lead to a variety of health problems, and the symptoms may mimic those of other diseases. That makes it difficult to diagnose, and it’s often too late by the time the disease is identified.

In fact, a confirmed diagnosis is usually only possible during a postmortem heart biopsy. Still, there are many tests veterinarians can run that will help find out if myocarditis is present. If you see the signs in your dog, then you must consult your vet as soon as possible for a diagnosis and proper treatment.

Here’s what you should know about the symptoms, causes, and treatments for myocarditis in dogs.

Symptoms Of Myocarditis In Dogs

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Symptoms of myocarditis in dogs can vary a bit depending on the cause, though they’re usually fairly similar.

If the cause of the condition is an infection, symptoms of that type of infection may appear at the same time as the signs of myocarditis. Sometimes symptoms may not appear until the disease is at an advanced stage, and when symptoms do appear, they may mimic those of other medical conditions.

If you see any of the following symptoms, consult your veterinarian as soon as possible:

  • Fever
  • Lethargy
  • Loss of appetite
  • Weakness
  • Arrhythmia (irregular heart beat)
  • Heart murmur
  • Cough
  • Ascites
  • Exercise intolerance
  • Difficulty breathing
  • Collapse
  • Sudden death

Causes Of Myocarditis In Dogs

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There are several possible causes of myocarditis in dogs. It can either be infectious–meaning it’s caused by bacterial, fungal, viral, or other kinds of infection–or it can be non-infectious, which means it’s caused by heart disease, mineral deficiency, physical injury, or exposure to toxins.

Here are several possible factors that can lead to myocarditis in dogs:

  • Lyme carditis (transmitted through tick bite)
  • Parvovirus
  • West Nile virus
  • Chagas’ disease
  • Ischaemic heart disease
  • Mineral deficiency
  • Vitamin E deficiency
  • Injury
  • Exposure to toxins
  • Endocardiosis
  • Polymyositis
  • Meningitis
  • Parasites
  • Severe exertion
  • Heat stroke

Treatments For Myocarditis In Dogs

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Treatment for myocarditis in dogs may require hospitalization until the dogs’ condition stabilizes. Goals of treatment include strengthening the heart muscle and reducing any heart arrhythmia that’s present, as well as preventing fluid buildup in the lungs and abdomen.

If an underlying infection is found, then the vet will treat it with medication and any other necessary treatment. Vets usually treat bacterial infections with antibiotics such as penicillin, and they treat fungal infections with antifungal medication.

Vets may treat viral infections with hospitalization and intravenous fluids, and they may manage some further symptoms with drugs.

In cases of ischaemic heart disease, vets can use a variety of medications, and they can often correct mineral or vitamin deficiencies with supplements. They will treat toxin exposure by removing as many toxins from the body as possible.

Vets may correct heart arrhythmias with medications, and some dogs who suffer from myocarditis may also need a pacemaker to regulate their heart beat. Vets may also prescribe dietary changes, including limiting salt intake.

The chances of recovery vary depending on how severe the disease is and how far it has progressed. Follow your vet’s instructions closely if they diagnose your dog with myocarditis.

Do you keep up with vet visits to catch any medical conditions early? How do you keep your dog’s heart healthy? Let us know in the comments below!