Myocarditis In Dogs: Symptoms, Causes, & Treatments

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Myocarditis in dogs, also known as heart inflammation, is a disease of the heart caused by swelling of the heart’s muscular wall, called the myocardium. It is usually caused by 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 essential to many of dogs’ bodily functions, myocarditis can cause a variety of health problems, and the symptoms may mimic those of other diseases. This makes myocarditis difficult to diagnose, and it is 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 determine myocarditis is present. If you see the signs of myocarditis in your dog, it is important that you consult your veterinarian as soon as possible for a diagnosis and proper treatment. Here is 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 of the condition, though they are usually fairly similar. If the cause of the condition is an infection, symptoms of that type of infection may appear simultaneously with 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. Myocarditis can either be infectious, meaning it is caused by bacterial, fungal, viral, or other kinds of infection, or myocarditis can be non-infectious, which means it is 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, reducing any heart arrhythmia that is present, and preventing fluid buildup in the lungs and abdomen.

If an underlying infection is found, it will be treated with medication and other treatment. Bacterial infections are usually treated with antibiotics such as penicillin, and fungal infections are treated with antifungal medication. Viruses may be treated with hospitalization and intravenous fluids, and some symptoms may be managed with drugs. Ischaemic heart disease can be treated with a variety of medications, and mineral or vitamin deficiencies are often corrected with supplements. Toxin exposure can be treated by removing as many toxins from the body as possible.

Heart arrhythmias may be corrected with medications, and some dogs that suffer from myocarditis may need a pacemaker to regulate their heart beat. Dietary changes may be prescribed, including limiting salt intake. The chances of recovery vary depending on how severe the disease is and how far it has progressed. Follow veterinary instructions closely if your dog is diagnosed with myocarditis.