What is a Heart Murmur in Cats?
A heart murmur in cats, similar to any animal, is classified as an abnormal heart sound. It is often described as a whooshing sound and is created when there is turbulence in the bloodstream as it flows through the heart.
What Could a Heart Murmur in Your Cat Mean?
1. Nothing
The good news is that heart murmurs are fairly common in cats. In fact, kittens 0-5 months commonly experience heart murmurs. These non-life-threatening murmurs are referred to as innocent or physiologic murmurs. Kittens will usually grow out of them between 4-5 months of age. However, heart murmurs can also occur in adult cats, though this is slightly less common. In these cases, temporary innocent or physiologic murmurs are usually caused by increased stress levels.
2. Extracardiac Conditions
A cat’s heart murmur could also be caused by conditions outside the heart, also known as extracardiac conditions. Heart murmurs are common symptoms of the following:
- Anemia
- High blood pressure
- Hyperthyroidism
However, they can also occur if the cat is:
- Fighting an infection
- Pregnant
- Obese
- Emaciated
3. Heart Disease
Heart murmurs can also be a sign of structural heart diseases or a heart defect from birth. These defects are classified as congenital heart disease. However, heart murmurs can also be a sign of adult-onset heart disease. This means that the disease was acquired over time as a result of damage to the heart structure. While the main cause of adult-onset heart disease is unknown, some factors such as weight, activity levels, and diet play an important role.
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What Should You Do if Your Cat is Diagnosed with a Heart Murmur?
1. If your cat is NOT showing other signs of an underlying problem:
Your vet may suggest a repeat examination after a few months to re-assess the problem. In this second examination, they will look for new signs of an underlying condition and check if the murmur has changed or is still present. If the heart murmur is not gone by the second evaluation your vet may suggest a blood panel, x-ray, electrocardiogram (ECG), or echocardiogram (ultrasound of the heart).
2. If your cat is showing other signs of an underlying problem:
Your vet may suggest taking immediate action to properly diagnose the underlying problem. Because there are many conditions that could cause a heart murmur in cats, there are many tests to be completed.
- Blood panel & urine panel
- Blood and urine panels rule out anemia, infections, kidney disease, liver disease, thyroid disease, and other medical abnormalities.
- X-ray
- X-rays confirm the presence of congestive heart failure and determine its severity.
- Electrocardiogram
- ECGs measure the electrical activity of your cat’s heart.
- Echocardiogram
- An Echocardiogram measures your cat’s heart and major cardiac vessels.
The Takeaway
Heart murmurs are very common in cats, and most of the time are a result of growth or stress. However, in some cases, a heart murmur in cats can signify an underlying problem. It is important to practice routine annual check-ups with your vet to properly manage your cat’s health and catch heart murmurs early.
Works Cited
Admin. “Heart Murmurs in Cats – Should You Be Concerned? – Vet Care in NE Portland, OR.” MetroVet, 3 July 2019, gometrovet.com/petcare-perspectives-blog/post/heart-murmurs-in-cats/.
“Cardiology For Cats.” Metropolitan Veterinary Center, 24 Jan. 2018, www.metrovetchicago.com/services/cats/heart-disease-in-cats.
Care, International Cat. International Cat Care, 6 Oct. 2019, icatcare.org/advice/heart-murmurs-in-cats/.
Cats, Heart Murmurs in, et al. “Heart Murmurs in Cats.” vca_corporate, vcahospitals.com/know-your-pet/heart-murmurs-in-cats.
Lorie Huston, DVM. “What Does a Heart Murmur Mean for Your Cat?” The Spruce Pets, www.thesprucepets.com/heart-murmurs-in-cats-3384633.
Sarah. “My Pet Was Diagnosed with a Heart Murmur! What Does That Mean?” Metropolitan Veterinary Associates, Metropolitan Veterinary Associates, 9 Dec. 2020, metro-vet.com/my-pet-was-diagnosed-with-a-heart-murmur-what-does-that-mean/.
