Dogs can live with heart disease for some time before showing obvious symptoms. Some have a murmur discovered at a routine checkup, while others first come to attention because their breathing or stamina has changed. Recognizing those changes is useful, but a cough alone does not prove that the heart is responsible.
Which changes should owners notice?
A dog with worsening cardiac disease may tire more easily, be reluctant to exercise or seem restless when trying to sleep. Breathing that is faster or more labored than usual is particularly important. Coughing can occur with some heart conditions, but respiratory infection, chronic airway disease and other problems can cause the same symptom.
Why monitor resting breathing?
For a dog with diagnosed heart disease, veterinarians may recommend measuring breathing when the dog is sleeping or truly relaxed. Record the number of breaths in a minute at a consistent time and look for a sustained rise from the dog’s usual pattern. Ask the cardiology team what changes warrant a call rather than relying on one universal cutoff or measuring immediately after excitement.
Does a murmur mean heart failure?
No. A heart murmur is a sound produced by blood flow, not by itself a diagnosis of failure. Some dogs have a murmur for years without signs of congestive heart failure. Your veterinarian may recommend chest imaging, blood pressure measurement, an electrocardiogram or echocardiography depending on the findings.
When is it an emergency?
Labored breathing, blue or gray gums, collapse, severe weakness or an inability to rest because of breathing distress requires emergency veterinary care. Don’t attempt to treat a suspected cardiac emergency with another pet’s medication or extra diuretics unless your own veterinarian has given a specific emergency plan.
What can help after diagnosis?
Follow the medication and dietary plan, keep planned rechecks and track changes in breathing and activity. The best treatment depends on the heart condition and stage; early evaluation can help the team decide when medication is needed.
See emergency signs in canine heart disease and feeding considerations.
Veterinary references
- Merck Veterinary Manual: Cardiovascular Disease in Dogs
- ACVIM: Canine Mitral Valve Disease Consensus Guidelines
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.