心脏杂音
Your child's doctor listens to their heart with a stethoscope to detect heart murmurs.
"Innocent" heart murmurs
Innocent heart murmurs are sounds made by blood circulating through the heart’s chambers 和 valves, or through blood vessels near the heart. Innocent murmurs are common in children 和 are harmless. These heart murmurs are also called “normal” or “physiological” murmurs.
Innocent heart murmurs are so common that around one-third to three-quarters of children will have an innocent murmur at some time between age 1 和 14. Innocent murmurs may disappear 和 then reappear. When a child’s heart rate changes, such as during excitement or fear, these 无辜的杂音 may become louder or softer. This still doesn’t signal that the murmur is cause for concern.
If your child's doctor hears a murmur when listening to their heart, they may recommend additional testing, 比如 心电图 (心电图)或 超声心动图 (回声). This is to confirm the murmur is innocent. Unless testing suggests otherwise, no additional steps may be needed.
With an innocent heart murmur, your child won’t need medication, 和 doesn't have a heart problem or heart disease. You will not need to restrict your child’s activities or diet. They can lead an active, healthy life!
Most 无辜的杂音 disappear when a child reaches adulthood, but in some adults the murmur remains for life.
阅读更多关于 无辜的杂音.
其他原因
Non-innocent (or abnormal) heart murmurs are often caused by defective heart valves. 例如，a 狭窄心脏瓣膜 has a smaller-than-normal opening 和 can’t open completely. Or a valve may also be unable to close completely. 这导致 返流, which is blood leaking backward through the valve when it should be closed.
某些 先天性缺陷 和 other conditions such as pregnancy, 发热, anemia or thyrotoxicosis (a condition caused by an overactive thyroid gl和) can also cause murmurs.
A murmur that occurs when the heart muscle relaxes between beats is called a diastolic murmur. A systolic murmur occurs when the heart muscle contracts.
Systolic murmurs are graded by intensity (loudness) from 1 to 6. A grade 1 is faint, heard only with a special effort. It's softer than the normal heart sounds. A grade 6 is extremely loud, 和 can be heard with no contact between stethoscope 和 the chest.
