It can be really unsettling to hear that your pet has a heart murmur. But before you panic, let’s take a look at what causes murmurs and what they mean for your pet’s health.

Simply put, murmurs are vibrations caused by abnormal blood flow through the heart or large blood vessels. Murmurs have lots of potential causes. For example, heart structures can be defective at birth, causing rerouting of the normal blood flow. Heart valves or walls can also become misshapen as dogs age. Even thin blood from anemia can cause a murmur.

Once your veterinarian detects a murmur, they’ll look for other signs and symptoms and conduct diagnostic tests to determine the cause and whether it needs to be treated. The sooner that happens, the better — before whatever’s causing the abnormalities lead to other problems.