During a physical exam, your doctor listens to your heart with a stethoscope.
Normal heart sounds
The doctor listens to your heart at different places on your chest to hear the sounds your heart valves make as blood travels through your heart. Normally, the heart beat has two sounds – lub-dub. The first sound is heard as the mitral and tricuspid valves close. The second heart sound is the aortic and pulmonic valves snapping shut.
A heart murmur is a swishing sound heard when there is turbulent or abnormal blood flow across the heart valve.
Murmurs can be present without any medical or heart conditions. Two common examples include:
- Childhood murmurs
Causes of heart murmurs
Valvular heart disease is the most common cause of a heart murmur.
- Valve stenosis – a narrow, tight, stiff valve, limiting forward flow of blood.
- Valve regurgitation – a valve that does not close completely, allowing backward flow (a "leaky" valve).
The abnormal changes to the valve cause the abnormal heart sound (murmur).
Other causes of heart murmurs include:
- Hypertrophic cardiomyopathy
- Septal defect
Functional causes for heart murmurs
Murmurs can be caused by increased blood flow across the valve related to other medical conditions without valvular heart disease, such as: