Heart Murmurs in Puppies

Some abnormal heart sounds are dangerous but early, thorough diagnosis is key to good outcomes.



I’m a proud owner of a beautiful Siberian Husky who is eight weeks old and is suspected to have a heart murmur.  If that is true what will happen to my puppy and will she be able to live a long life? I’m worried to death.


Dr. Nichol:

I understand how you feel. If you learn more about heart murmurs you’ll feel better. Using a stethoscope we can hear the extra heart sounds that are called murmurs. It’s a shhh sound during the lub-dub of the normal heartbeat. In some puppies murmurs are caused by the flow of blood through a passageway that should have closed before birth. In others the sound can result from blood shooting through a normal passage that’s abnormally narrow.


We see a lot of these in our practice but to make sure you’re getting the latest I contacted Dr. Larry Tilley, a board certified veterinary cardiologist. Here’s the scoop: many low volume murmurs (what we call Grade I) will resolve all by themselves in just 2-3 weeks. These are called innocent or growth murmurs. They mean nothing. These puppies grow to adulthood normally. But for puppies whose murmurs remain we become concerned about the future. Dr. Tilley’s recommendation is to have that heart examined again in a few weeks. If the murmur is still there have the doctor take chest X-rays and an electrocardiogram (ECG). If she tests normal she should be rechecked when she is fully-grown. If her tests are still fine her future should be bright. If her tests are not fine other diagnostic work can be done. There are several possible causes; two of them are curable.


For now try not to worry. Your little girl is having great fun being a goofy kid. Share that joy and take one day at a time. Based on a lot of experience with these I can tell you that the great majority of puppies with heart murmurs grow up strong and healthy. Now throw down this newspaper and run around the yard with that Husky girl.