Murmurs are blowing, whooshing, or rasping sounds heard during a heartbeat. The sound is caused by turbulent blood flow through the heart valves or near the heart.
A doctor can check heart sounds by listening with a stethoscope over the surface of the chest. An echocardiogram can find the exact cause of the murmur.
The heart has four chambers: two upper chambers (atria) and two lower chambers (ventricles). The heart has valves that close with each heartbeat, causing blood to flow in only one direction. The valves are located between the atria and ventricles, and between the ventricles and the major vessels from the heart.
Murmurs occur when a valve does not close tightly and blood leaks backward (called regurgitation). They also can occur when the blood flows through a narrowed or stiff valve (called stenosis).
There are several ways in which your doctor may describe a murmur:
When a murmur is more prominent, the doctor may be able to feel it with the palm of the hand over the heart.
The following are important clues to the cause of the murmur:
For example, a presystolic murmur is heard just before systole. It is usually caused by narrowing of the mitral or tricuspid valve (the valves between the atria and the ventricles).
Many heart murmurs are harmless. These types of murmur are called innocent murmurs. They will not cause any symptoms or problems. Innocent murmurs do not need treatment.
Significant murmurs can be caused by:
Significant murmurs in children are more likely to be caused by:
Children often have murmurs as a normal part of development. These murmurs do not require treatment, and may include:
The health care provider will usually discover a heart murmur during a physical examination. You may or may not have been aware of its presence. The physical examination will include careful attention to heart sounds.
The doctor may ask the following questions:
The health care provider can often identify the valve involved and whether you have regurgitation or stenosis during the exam. The location, quality, and timing of the murmur are all important. The doctor may ask you to squat, stand, or hold your breath while bearing down or gripping something with your hands to listen to your heart.
Diagnostic testing to determine the cause of a "new" murmur or other abnormal heart sound may include:
Chest sounds - murmurs; Heart sounds - abnormal; Murmur - innocent; Innocent murmur; Systolic heart murmur; Diastolic heart murmur