Munson Health
Heart Murmur

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by Alan R


Benign murmurs are caused by the normal flow of blood through the heart and large vessels near the heart. The murmur may come and go over time. Some things that can increase blood flow and cause a benign heart murmur to be heard include:
Abnormal heart murmurs can be due to:


Most benign heart murmurs are diagnosed during the course of a routine physical exam with a stethoscope. Some abnormal heart murmurs are also discovered this way. Other abnormal heart murmurs are discovered initially by their symptoms.
Tests may include:
  • Electrocardiogram (ECG)—This does not diagnose the cause of the murmur but can provide other useful information about the condition of the heart.
  • Chest x-ray —to determine the approximate size and shape of the heart, and the presence of associated lung swelling (pulmonary edema).
  • Echocardiogram —to examine the size, shape, and motion of the heart.
  • Cardiac catheterization —to detect problems with the heart's structure, function, and blood supply.
  • Blood tests—To check for evidence of a recurrent heart attack or other diseases that may affect the heart (such as kidney disease, infections, autoimmune conditions).


Preventing benign heart murmurs is unnecessary. To help reduce your risk of developing an abnormal heart murmur:
Although not routinely recommended for every type of heart murmur, you may need to take antibiotics before and after some medical or dental procedures that could allow bacteria to enter your bloodstream. Ask your doctor if you need to take preventive antibiotics.


American Heart Association

Heart Information Network



Canadian Cardiovascular Society

Canadian Family Physician



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American Heart Association. New guidelines regarding antibiotics to prevent infective endocarditis. American Heart Association website. Available at: . Accessed August 30, 2010.

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Heart murmurs. Mayo Clinic website. Available at: . Updated April 9, 2010. Accessed February 9, 2012.

Heart murmurs and your child. KidsHealth website. Available at: . Updated August 2010. Accessed February 9, 2012.

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