A heart murmur typically sounds like a whooshing noise. As the American Heart Association (AHA) mentions it, a heart murmur feels like a very subtle extra pulse. It is commonly seen among young children. Studies and research have shown that almost half of all the children will have innocent heart murmurs at some point, which will fade away as they grow.
Heart murmurs can develop in adults as well, especially when they are fifty years of age or older. Sometimes, they can occur when you have a fever or are pregnant.