Heart and Blood Conditions

Heart Murmurs

What are heart murmurs?

What does a heart murmur sound like?

Heart murmurs are sounds that a healthcare provider may hear when listening to the heart through a stethoscope. A murmur may sound like whooshing, rasping or blowing, and comes from blood moving through the heart.

Most heart murmurs in children are innocent, or harmless. Occasionally a murmur is from a structural heart defect. It's important to have abnormal sounds checked, because they might mean there's a problem in the heart.

Murmurs are graded on how easily they're heard by the healthcare provider. The grading is on a scale of one to six, with grade six being the loudest. Just because a murmur is louder does not necessarily mean that the murmur is something to be worried about.

Heart Murmurs in Children

The majority of murmurs heard in children are just the sounds of blood moving through the heart. More than half of all children will have a heart murmur at some time, but less than 1% of all children have a structural heart defect that may cause a murmur.

Not all murmurs are signs of a heart problem. Sometimes, a murmur is heard in a child who has a fever or who is anemic (low red blood cells), and the murmur goes away when the child gets treatment for the condition that caused it. Usually, these murmurs are harmless murmurs that became louder and easier to hear because of increased blood flow through the heart when the child is sick.

Heart Murmurs at Seattle Children's

Our heart team has evaluated many children with heart murmurs. We have extensive experience with the conditions that can cause heart murmur and with the treatments they may require. Often we can tell if a murmur is harmless by just listening to it. When needed, we perform tests as part of the evaluation.

Children who have a heart defect that caused their murmur may need medicines, cardiac catheterization or heart surgery to treat their condition. We have a team of specially trained cardiologists (physicians), nurses and technicians who have expertise in evaluating and treating children with heart defects. We have a pediatric cardiac anesthesia team and a cardiac intensive care service ready to care for children who undergo heart surgery.

When you come to Seattle Children's, a team of people will take care of your child. Along with your child's cardiologist, you are connected with neonatologists, pulmonologists (lung doctors), nurses, child life specialists, social workers and others, if their expertise is needed. We work together to meet all of your child's health needs and help your family through this experience.

Seattle Children's has been treating children since 1907. Our team members are trained in their fields and also in meeting the unique needs of children. For example, the doctors who give your child anesthesia are board certified in pediatric anesthesiology. This means they have extra years of training in how to take care of kids. Our child life specialists know how to help children understand their illnesses and treatments in ways that make sense for their age.

Contact Us

Contact the Heart Center at 206-987-2015 for a cardiac referral, a second opinion or more information.