A heart murmur in dogs can be an early clue that something more serious is going on inside your pup’s chest. But not all heart issues make noise. Some dogs show subtle signs that are easy to miss unless you know what to look for. Whether your dog has already been diagnosed with a murmur or you’re just trying to stay ahead of health problems, understanding the early signs of heart disease is essential.
In this blog, we’ll go beyond the murmur to highlight the hidden signs of heart trouble in dogs and what you can do to help your pet live a healthy, comfortable life.
A heart murmur is the sound of turbulent blood flow within the heart. It may be caused by a structural abnormality—such as a leaky valve—or simply be an innocent murmur found in puppies that fades over time. However, not all heart issues come with an audible murmur. Some heart problems progress silently until they start affecting your dog’s quality of life.
If your dog used to love fetch but now gets tired quickly or lies down during walks, it might be more than just aging. Dogs with heart issues may not be able to get enough oxygen-rich blood to their muscles, leading to fatigue even during mild activity.
Chronic or occasional coughing, especially after activity or while lying down, can be linked to fluid buildup in the lungs (pulmonary edema), which is common in congestive heart failure (CHF). Some dogs cough due to an enlarged heart pressing on the airway.
Heart disease often causes general fatigue, where dogs sleep more, seem less interested in interaction, and struggle to keep up with their usual routine.
If your dog seems to be breathing fast, even at rest, or you notice exaggerated chest movement, this may indicate respiratory distress due to fluid accumulation or decreased oxygen flow from heart dysfunction.
Dogs with more advanced heart issues may faint during exertion or excitement. These episodes can resemble seizures but usually involve sudden collapse with quick recovery.
A swollen belly can be a sign of ascites, or fluid buildup, which sometimes happens in right-sided heart failure. If your dog gains weight but seems thinner in the face or back, this could be fluid retention—not fat.
Normal gums are bubblegum pink. If your dog’s gums look pale or bluish, this may point to poor oxygen circulation—a sign the heart is struggling.
Dogs with heart failure may feel more discomfort while lying down and become restless at night. You might notice them shifting positions frequently or preferring to sit up.
If your dog suddenly loses interest in food without another obvious cause, it could be related to fatigue, fluid buildup, or general discomfort from declining heart function.
If your dog is showing one or more of these signs, schedule a visit with your veterinarian. Early diagnosis can make a significant difference in treatment and prognosis. A thorough physical exam, chest X-rays, ECG, and echocardiogram (ultrasound of the heart) are common diagnostic tools.
While not all heart murmurs or heart problems are dangerous, some require medical management or even long-term medication. Treatment may include:
Diuretics to remove excess fluid
ACE inhibitors to ease the heart’s workload
Pimobendan to strengthen heart contractions
Low-sodium diets and supplements like taurine or CoQ10
Lifestyle adjustments (light exercise, stress reduction)
With the right care, many dogs with heart issues can live happy, fulfilling lives for years.
Not all heart issues in dogs are immediately obvious. That’s why it’s important to pay attention to subtle changes in your dog’s behavior and energy. If something feels “off,” don’t write it off as aging or laziness. A timely vet check can make a big difference.
Heart murmurs can be caused by congenital defects, valve problems, heartworm disease, or age-related degeneration. In puppies, some murmurs are innocent and resolve on their own.
Yes, especially puppies. Many young dogs with innocent murmurs grow out of them as their circulatory systems mature. However, a follow-up vet exam is essential.
Not always. Coughing can also be caused by allergies, tracheal collapse, or infections. However, persistent coughing—especially in senior dogs—should be evaluated.
Small breeds like Cavalier King Charles Spaniels, Dachshunds, and Chihuahuas are prone to mitral valve disease. Large breeds like Boxers and Dobermans are more prone to dilated cardiomyopathy.
Most heart conditions in dogs can’t be cured but can often be managed with medication, diet, and lifestyle changes. Early diagnosis helps improve outcomes.
I drove around to multiple puppies stores in Boca and Waggs is where I found my Shih Tzu puppy. They by far have the cutest puppies and cleanest store.
~ Jacob Anthony