If your dog has been diagnosed with a heart murmur, you might feel unsure about what that means or what comes next.
A murmur isn’t always a cause for alarm, but it is worth investigating. A trusted veterinarian will carefully examine your dog’s heart, recommend appropriate tests, and guide you through a personalised care plan.
We’re here to help you understand what a heart murmur is, what causes it, and how we manage it to keep your dog feeling their best.
What Is a Heart Murmur?
A heart murmur is an unusual sound a trusted vet hears when listening to your dog’s heart with a stethoscope.In a healthy heart, a careful vet gets a distinct and regular rhythm as the valves open and close.
This produces a whooshing or swishing sound, indicating that blood is being circulated abnormally within the heart. Murmurs might be quiet or soft or loud and easy to hear. Experienced vets grade murmurs from 1 to 6, with 1 being the quietest and 6 the loudest.
Not every murmur is harmful; however, it is considered an early indication of heart disease. For this reason, your vet will usually refer you for further tests.
What Causes a Heart Murmur in Dogs?
A murmur typically arises when something alters the way blood travels through the heart. This could be because of:
- Mitral valve disease, especially in older miniature-breed dogs
- Dilated cardiomyopathy, where the heart muscle is enlarged and weakened
- Congenital heart lesions such as holes in the heart or malformed valves (commonly occurring in puppies)
- Heartworm disease, caused by parasites in the heart and lungs
- Endocarditis, which is infection of the heart valves
- Tumours adjacent to or within the heart
Some puppies possess what is called an “innocent murmur.” These are typically benign and fade as the puppy matures.
Does a Murmur Mean My Dog Has Heart Disease?
Not always. A murmur is a hint that something might be happening to the blood flow, but it doesn’t make the diagnosis. To know what’s doing it, we typically have to take more tests. At Centenary Vets, we create diagnostic plans suited to your dog’s age, breed, and symptoms.
Signs of Heart Trouble to Watch For
A few dogs with heart murmurs do not show any obvious signs initially. But when heart disease occurs at a later stage, it can manifest very typical symptoms such as
- Persistent coughing, especially during the night or after exercises
- Difficult or panting breaths; Less endurance at walking or playing
- Decrease of appetite or loss of interest in activities
- Collapse or faint
- Swelling in the abdomen.
- Pale or blue-tinged gums.
If you see such a sign, the most important action is to take them to a vet. Such indications may show that your dog’s heart disease is worsened.
What Tests Will My Vet Recommend?
When a murmur is detected, your vet may suggest the following tests:
Blood Tests
To assess your dog’s overall health, look for infections, and check for heartworm.
Chest X-rays
To check the size and shape of the heart and look for fluid in the lungs.
Electrocardiogram (ECG)
To evaluate the heart’s electrical activity and check for irregular rhythms.
Echocardiogram (Ultrasound of the Heart)
Considered the most accurate way to view the heart in real time.
According to Animal Medicines Australia, early diagnosis using imaging tools can lead to more effective treatment plans.
Blood Pressure Measurement
High blood pressure can contribute to worsening heart problems and needs to be monitored regularly.
At Centenary Vets, we take the time to explain these options and help you choose the right path forward for your pet.
What’s the Treatment for a Heart Murmur?
Treatment varies with the cause and severity of the murmur. If your dog has a mild murmur and no symptoms, we might just monitor it.
If heart disease is diagnosed or if symptoms are detected, medication typically is in order.
Centenary Vets‘ staff tailor each treatment plan to individual dog needs. Our objective is to enhance comfort, prolong quality of life, and minimise the workload on the heart.
Common Medications for Dog Heart Disease
Pimobendan (Vetmedin, Cardisure)
It helps the heart pump more effectively and reduces strain. Often used in early-stage heart disease.
Diuretics (e.g. Frusemide)
Help remove excess fluid from the lungs or abdomen, easing breathing.
ACE Inhibitors (e.g. Fortekor, VetAce)
Lower blood pressure and reduce the heart’s workload, often used in combination with other drugs.
Your vet will guide you through the most suitable medications and monitor your dog’s response closely.
How Often Should My Dog Be Checked?
Dogs with heart murmurs need regular monitoring, even if they appear healthy. Here’s a general guide:
- Heart ultrasound: every 6 to 12 months
- Chest x-rays: every 6 to 12 months
- Blood tests: every 6 to 12 months, especially if medication is being used
- Blood pressure: every 6 months
- Vet check-up: every 6 months to assess any changes and renew prescriptions
If your dog’s condition changes, more frequent visits may be recommended. Centenary Vets Commitment 2 Care Plans are designed to make preventative pet healthcare more accessible by bundling regular check-ups, ongoing diagnostic monitoring, and discounted medications.
These plans help ensure your pet receives consistent, high-quality care without unexpected costs, and you’ll often see the same vet at each visit for continuity and peace of mind.
What to Remember About Heart Murmurs
A heart murmur doesn’t always mean serious illness, but it’s something that deserves attention. With the right care and ongoing monitoring, many dogs live long and comfortable lives even with a heart condition.
The team at Centenary Vets is here to provide expert advice, gentle care, and support every step of the way. If you have concerns about your dog’s heart or want to book a consultation, we’re here to help.
