What is a heart murmur? What are some common reasons that heart murmurs occur?

They are ‘whooshing’ sounds your heart makes (Instead of ‘lub-DUBB’) which can be heard through a stethoscope. They can either be harmless, ‘innocent’, or caused by disease. In children, abnormal murmurs are usually caused by congenital heart disease. In adults, abnormal murmurs are most often due to acquired heart valve problems.