A heart murmur is an abnormal sound in the heart. It results from blood flowing over or through an irregular surface. Not all murmurs are associated with conditions that require surgery. There are two types of murmurs – innocent murmurs and abnormal murmurs. Innocent murmurs are harmless and usually require no treatment. Abnormal murmurs are commonly caused by congenital defects in children and, in adults, are usually due to heart valve problems. Signs of an abnormal murmur include a blue colouring to the skin, poor eating and failure to grow (in infants), fast breathing, excessive sweating, chest pain, dizziness, shortness of breath, fainting, and fatigue. Treatment options include treating the underlying cause, medication, and surgery.