Common Heart Conditions in Dogs and Breeds at Risk

Just like in humans, heart health plays an important role in a dog's overall well-being. The heart works continuously to pump oxygen-rich blood throughout the body, supporting every organ and tissue. When heart function becomes impaired, it can affect everything from a dog's energy level and breathing to appetite and ability to exercise.

Some heart conditions develop as dogs age, while others may have a genetic or breed-related component. Knowing the common signs of heart disease and understanding whether your dog's breed may be at greater risk can help you recognize potential problems earlier.

Here are some common canine heart conditions and what pet parents should know about them.

◉ Dilated Cardiomyopathy (DCM)

Higher-Risk Breeds: German Shepherds, Golden Retrievers, Doberman Pinschers, and Labrador Retrievers.

Dilated cardiomyopathy, commonly called DCM, is a disease of the heart muscle. The heart becomes enlarged and the muscle becomes weaker, reducing its ability to contract effectively and pump blood throughout the body.

As the condition progresses, fluid may accumulate in or around the lungs, and some dogs may develop abnormal heart rhythms.

DCM is more frequently seen in large and giant breeds, although it can occur in other dogs as well.  Early DCM may not cause obvious symptoms. This is one reason routine veterinary examinations can be particularly important for breeds with a known predisposition.

As the disease progresses, pet parents may notice reduced stamina, weakness, coughing, rapid or difficult breathing, abdominal enlargement, or fainting. Veterinarians may use several diagnostic tools to evaluate suspected DCM, including chest X-rays, an electrocardiogram (ECG), blood tests, and an echocardiogram to examine the heart's structure and function.

◉ Hypertrophic Cardiomyopathy

Higher-Risk Breeds: Chihuahuas, Bichons

Hypertrophic cardiomyopathy, or HCM, occurs when the muscular walls of the heart become abnormally thickened. The thickened heart muscle can make it more difficult for the chambers of the heart to fill properly with blood. 

When thickening of the heart muscle is identified in a dog, veterinarians may investigate possible underlying causes and other conditions that can affect the heart. Because different heart diseases can produce similar symptoms, an accurate diagnosis is essential. An echocardiogram is particularly useful because it allows a veterinarian or veterinary cardiologist to examine the thickness of the heart walls, chamber size, valves, and blood flow.

◉ Mitral Valve Regurgitation

Higher-Risk Breeds: Cavalier King Charles Spaniel, Dachshund, Miniature Poodle, Chihuahua, Yorkshire Terrier, Maltese, Miniature Schnauzer

A common heart disease in dogs caused by age-related changes to the valves of the heart. Common in senior and small breed dogs, such as Maltese, Spaniels, Yorkshire Terriers, Poodles, Schnauzers, and Chihuahuas.

【Symptoms of Dogs with Heart Disease】

Heart disease does not always produce obvious signs in its early stages. Symptoms can also vary depending on the type and severity of the condition.

Pet parents should watch for:

➊ Coughing

Persistent coughing, particularly at night or during rest, should be discussed with your veterinarian. However, coughing can have many causes other than heart disease.

➋ Rapid Breathing

Changes in breathing can be an important warning sign. A dog may breathe faster than usual while resting or appear to work harder to breathe.

➌ Fatigue and Weakness

A dog that previously enjoyed long walks may begin slowing down, stopping frequently, or showing less interest in physical activity.

➍ Unexplained Weight Changes

Some dogs with chronic heart disease may lose weight or muscle mass. Fluid retention can also cause changes in body weight or abdominal appearance.

➎ Decreased Appetite

Dogs that feel unwell may become less interested in food or have difficulty maintaining their usual appetite.

➏ Fainting

Sudden fainting or collapse can occur when blood flow or heart rhythm is significantly affected and should always be taken seriously.

Other possible signs include restlessness at night, abdominal swelling, reduced exercise tolerance, and changes in normal behavior.

Difficulty breathing, collapse, pale or bluish gums, or severe weakness should be treated as an emergency and require immediate veterinary attention.

Supporting Heart Health in Dogs

Some canine heart conditions are strongly influenced by genetics and age, so they cannot always be prevented. However, good everyday care can support your dog's overall cardiovascular health and may help identify problems earlier.

➊ Regular Health Checkups

Routine veterinary examinations are one of the most important steps you can take. During a physical examination, your veterinarian can listen to your dog's heart for murmurs or abnormal rhythms and evaluate other signs that may require further investigation. Senior dogs and breeds predisposed to certain heart conditions may benefit from more frequent monitoring.

➋ Choose a Balanced and High-Quality Diet

Proper nutrition supports overall health, including normal heart function. Choose a complete and balanced diet appropriate for your dog's age, size, activity level, and health status. Avoid making major dietary changes or adding large amounts of individual nutrients without professional guidance. If your dog has already been diagnosed with heart disease, your veterinarian may recommend specific nutritional adjustments based on the condition and stage of disease.

➌ Supplement Heart Health Products

Certain nutrients, including omega-3 fatty acids and taurine, have roles in normal body and heart function. However, more is not necessarily better. Supplements should not be used as a replacement for a balanced diet or prescribed heart medication. If your dog has heart disease or belongs to a higher-risk breed, discuss supplements with your veterinarian before adding them to the daily diet.

➍ Maintain a Healthy Weight

Excess body weight places additional strain on the body and can make physical activity more difficult. Keeping your dog at an appropriate body condition through portion control, balanced nutrition, and regular activity supports overall health.

➎ Moderate Exercise

Regular exercise helps maintain muscle strength, mobility, and a healthy body weight. The appropriate amount depends on your dog's age, breed, fitness level, and health. Dogs diagnosed with heart disease may require modifications to their exercise routine, so follow your veterinarian's recommendations.

➏ Stress Management

Excitement and stress temporarily increase the body's demand for oxygen and affect heart rate. Providing your dog with predictable routines, adequate rest, comfortable sleeping areas, and appropriate enrichment can contribute to overall well-being.

➐ Regular Dental Care

Dental care is an important part of your dog's overall health. Regular tooth brushing, professional dental examinations when needed, and appropriate oral care can help control dental disease and reduce inflammation and infection in the mouth.

Early Detection Makes a Difference

One of the challenges of canine heart disease is that a dog can appear completely normal during the early stages.

Regular veterinary examinations become increasingly important as dogs grow older, particularly for breeds with known predispositions to heart disease.

At home, pay attention to changes in your dog's breathing, appetite, activity level, exercise tolerance, and behavior. If something seems different, don't wait for symptoms to become severe before speaking with your veterinarian.

A heart condition doesn't automatically mean a dog cannot continue to enjoy a good quality of life. With appropriate veterinary care, regular monitoring, nutrition, exercise management, and treatment when necessary, many dogs with heart disease can continue enjoying plenty of happy moments with their families.