Heart murmurs in dogs can be a concerning discovery for pet owners. While a murmur may sometimes
indicate a serious condition, it’s important to understand what it is, why
it occurs, and how it is managed. This arƟcle will provide a
comprehensive overview of heart murmurs in dogs, including their
causes, diagnosis process, treatment options, and answers to frequently
asked questions.
What is a Heart Murmur?
A heart murmur is an abnormal sound heard during a heartbeat. It is
caused by turbulent blood flow within the heart or its major vessels. This
sound is detected using a stethoscope and is described as a whooshing
or swishing noise that can vary in pitch and duration.
Causes of Heart Murmurs
Heart murmurs in dogs can be classified into two main categories: innocent (physiologic) murmurs and
pathologic murmurs.
1. Innocent Murmurs:
o Puppies: It is common for young puppies to have innocent murmurs. These murmurs are
usually harmless and often resolve as the puppy matures.
o Healthy Adults: Some adult dogs may have innocent murmurs due to temporary
conditions like stress or excitement, which typically resolve without treatment.
2. Pathologic Murmurs:
o Congenital Heart Defects: Some dogs are born with heart abnormalites, such as patent
ductus arteriosus (PDA) or ventricular septal defects (VSD), which can cause murmurs.
o Acquired Heart Diseases: Conditons like mitral valve disease, dilated cardiomyopathy,
or heartworm disease can lead to pathologic murmurs.
o Other Causes: Tumors, infecƟons, or inflammaƟon affecƟng the heart can also result in
murmurs.
Diagnosis of Heart Murmurs
When a heart murmur is detected, a veterinarian will conduct a thorough examinaƟon to determine its
cause. The diagnostic process generally involves:
1. Physical ExaminaƟon: The vet will listen to the heart and lungs, noƟng the murmur’s Ɵming,
locaƟon, and intensity.
2. Diagnostic TesƟng:
o Chest X-rays: These help visualize the heart’s size and shape and detect any enlargement
or fluid buildup.
o Echocardiography (Ultrasound): This provides detailed images of the heart’s structure
and function, helping to identify abnormaliƟes.
o Electrocardiogram (ECG): An ECG measures the electrical acƟvity of the heart and can
help diagnose arrhythmias or other electrical abnormaliƟes.
o Blood Tests: These can help determine if there are underlying conditions affecting the
heart.
Treatment Options
Treatment for a heart murmur depends on its underlying cause:
1. Innocent Murmurs: Typically require no treatment. Regular check-ups may be advised to
monitor the murmur and ensure the dog remains healthy.
2. Pathologic Murmurs:
o MedicaƟons: Depending on the condition, medications may be prescribed to manage
symptoms or improve heart function. For example, diuretics may help reduce fluid
buildup, while ACE inhibitors can help manage heart failure.
o Surgery: In some cases, surgical intervention may be necessary to correct congenital
defects or remove tumors.
o Lifestyle Adjustments: Changes in diet, exercise, and weight management may be
recommended to support heart health.
Frequently Asked Questions (FAQs)
1. How can I tell if my dog has a heart murmur?
A heart murmur is usually detected by a veterinarian during a rouƟne physical exam. However, signs that
may prompt further investigation including coughing, difficulty breathing, lethargy, or fainƟng.
2. Can heart murmurs be hereditary in dogs?
Yes, some heart conditions that cause murmurs can be hereditary. Certain breeds are more prone to
congenital heart defects or inherited heart diseases. Regular check-ups and screening are important for
breeds at higher risk.
3. Is a heart murmur always a serious condition?
Not always. Innocent murmurs, especially in puppies, are usually benign and resolve on their own.
However, pathologic murmurs can indicate underlying heart disease, which may require treatment. It’s
essenƟal to have any detected murmur evaluated by a veterinarian.
4. What is the prognosis for dogs with heart murmurs?
The prognosis varies depending on the cause of the murmur. Dogs with innocent murmurs typically have
a good prognosis. For dogs with pathologic murmurs, early diagnosis and appropriate treatment can
improve quality of life and manage symptoms effectively.
5. How often should my dog be checked if it has a heart murmur?
The frequency of check-ups depends on the murmur’s cause and severity. For innocent murmurs, annual
check-ups may be sufficient. For pathologic murmurs, more frequent monitoring may be necessary to
track the condition and adjust treatment as needed.
6. Can heart murmurs be prevented?
While not all heart murmurs can be prevented, maintaining overall heart health through a balanced diet,
regular exercise and rouƟne veterinary care can help reduce the risk of developing heart disease.
7. Are there any specific dietary recommendations for dogs with heart murmurs?
Dietary recommendations may vary based on the underlying condition. For dogs with heart disease, a
diet low in sodium and rich in essential nutrients may be beneficial. Your veterinarian can provide
specific dietary advice tailored to your dog’s needs.
8. What are the signs that my dog’s condition might be worsening?
Signs of worsening heart disease may include increased coughing, labored breathing, reduced exercise
tolerance, sudden weight loss, or fainƟng. If you notice any of these symptoms, contact your veterinarian
promptly.