Heart Disease In Dogs: Types, Signs, and Treatment

We hear time and again how to protect ourselves from heart disease: put down the bacon, go on a walk, manage stress, and visit our doctors. But is the same true for our dogs? 

The answer is yes, a healthy diet and exercise are integral for your pet’s well-being, but these factors are more important in human heart health. Why? Because the leading type of heart disease in humans is coronary artery disease, which is the buildup of plaque in the arteries that supply oxygen-rich blood to your heart. Risk factors for coronary artery disease are obesity, physical inactivity, unhealthy eating, and smoking tobacco. Dogs generally do not suffer from this condition; instead, degenerative valve disease accounts for 75% of cardiovascular disease in the species. The risk factors here are age and small-size breed. 

It is frightening to think about our dog’s suffering in any fashion. Here are some things every pet owner should know about heart disease in dogs, as proper diagnosis and treatment of heart disease can improve your dog’s quality of life and keep your dog’s heart beating for years to come. 

What is Heart Disease In Dogs?

Like heart disease in humans, when heart disease develops in a dog, the heart must adapt or change to continue working efficiently and bringing oxygen to the rest of the body. Heart failure in dogs is a complex condition that can develop congenitally (heart abnormality present from birth) or from acquired heart disease in dogs. 

  • Congenital conditions can be a result of a breed’s predisposition or an inherited condition. Congenital conditions make up a minority of canine heart disease. It is crucial to detect a congenital heart defect as early as possible, as surgery and treatment can help before the defect leads to congestive heart failure or irreversible heart damage. 
  • Acquired conditions make up the majority of canine heart disease cases. Typically, this is a result of wear-and-tear, which comes with aging. 
    • Degenerative Valve Disease is the most common heart disease in dogs and accounts for about 75% of cardiovascular disease in the species. The disease is age- and breed-related. There is research that suggests the condition is inherited in Cavalier King Charles Spaniels and Dachshunds. 
    • Dilated Cardiomyopathy (DCM) is more common in larger dogs, and it causes the progressive loss of the heart muscle’s ability to contract. The cause of this form of heart disease is unknown, but genetic factors seem to play a role; other risk factors include amino acid deficiencies (taurine, carnitine). Occasionally, DCM-like heart muscle dysfunction develops secondary to an identifiable cause such as a toxin or an infection. 
    • Heartworm Disease makes up 13% of canine heart disease even though it is entirely preventable. It is a serious and potentially fatal disease caused by the parasite Dirofilaria immitis. Heartworms cause disease by clogging the heart and major blood vessels leading from the heart. 

What Are The Signs and Symptoms of Dog Heart Disease 

The clinical signs of heart disease depend on the type of disease and severity. Your pup may be asymptomatic early on, making it essential to take your dog to the vet every year to screen for heart disease. 

  1. Congenital Heart Defects: Mildly affected dogs may be largely asymptomatic and live a normal life span. Congenital heart defects produce signs that vary depending on the type and severity of heart disease involved. Possible symptoms include shortness of breath or difficulty breathing, coughing, fainting, fatigue, or fluid accumulation in the lungs or abdomen.
  2. Degenerative Valve Disease: In dogs, there are no signs during the early stages of the disease, although a heart murmur can be heard. As the disease progresses, though, affected dogs may be slower to move or exercise, have difficulty breathing, and develop a cough. 
  3. Dilated Cardiomyopathy: The signs of DCM vary by breed, but include weakness, fainting, caught, and accumulation of fluid in the chest or abdomen. 
  4. Heartworms: Common signs of heartworm infection in dogs include: coughing, exercise intolerance, failure to grow, labored breathing, blue or purplish discoloration of the skin and gums, spitting up blood, fainting, nose bleeding, and accumulation of fluid in the abdominal cavity. 

In general, it is crucial to take your pup to the vet if you suspect any of these conditions, and even if you don’t, just for a checkup. Vets will perform x-rays, listen for murmurs or irregular heartbeats, and perform ECGs of cardiac ultrasounds. In general, here are symptoms to look out for 

  • Dry cough that follows physical activity or intensifies at night 
  • Shortness of breath or elevated breathing  
  • Restlessness when sleeping
  • Rapid weight loss 
  • Fainting — which can look like a seizure 
  • Potbelly caused by fluid buildup 
  • Rapid tiring or fatigue 

Treatment and Prevention 

There is no single way to prevent heart disease in dogs. Heart disease is an umbrella term for a plethora of conditions such that treatments are wide-ranging and broad. Most forms of heart disease in dogs cannot be prevented except for heartworm disease. Keeping your pet on year-round heartworm preventatives can protect your pet from getting this deadly disease. 

Catching heart disease early can be life-saving. Knowing what signs to watch for and faster diagnosis can mean more immediate treatments, generally daily medication. For dogs with congenital disorders, surgery may be possible. If an acquired heart condition is caught in the preclinical stage, medicine can prolong the symptom-free stage and overall survival. 

There is ongoing research about the implications of dietary and lifestyle choices on dog heart disease. Studies have shown an association between omega-3 deficiencies and taurine (amino acid) deficiencies in dogs with heart disease. Of course, it is best to consult with a veterinarian before shifting your puppy’s diet, as they can determine the most appropriate nutrient profile at each stage of your dog’s heart disease progression. 


The ElleVet Team
844-673-7287
[email protected]

×