From ArticleWorld

A stethoscope is a medical device that magnifies the sounds inside the body. It is used to hear normal and abnormal heart sounds, the sounds made during breathing, fetal heart sounds, abdominal sounds and abnormal arterial sounds.


Acoustic stethoscopes are the common type worn by most health professionals. The sounds are transmitted from the chestpiece, usually a flat diaphragm or a concave bell-shaped piece of metal through which sound is transmitted through one or two hollow tubes where it is augmented and heard by the listener who has an earpiece in each ear. The bell aspect of the stethoscope hears low frequency sounds better than the diaphragm, which hears high frequency sounds more easily.

Electronic stethoscopes amplify body sounds electronically. One such device is an electronic monitoring device for the amplification of fetal heart tones so that both parents and the physician can hear the heart beat.


The stethoscope is a commonly-used medical device. It is used in cardiology to hear the normal closure of the valves of the heart. The atrial valves usually close synchronously and the ventricular valves close at the same time as well. In certain types of heart disease extra sounds can be heard when a valve closes later than its matching one. Backflow through a leaky valve, a condition called regurgitation, can cause a “murmur” to be heard after a leaky valve closes. These are considered abnormal heart sounds.

The stethoscope can be used to determine the sounds of breathing. This is done while the patient breathes with the mouth open. Fluid within the lungs cause a sound known as “rales” and collapse of the bronchial tubes produce the sounds of wheezing during exhalation.

Abdominal sounds or the normal sounds of air flowing through the intestines can be heard through the use of a stethoscope. The absence of such sounds is considered a sign that the bowels might be inflamed or that they have somehow shut down.

Fetal heart sounds can be heard with a special electronic stethoscope or through a traditional fetal acoustic stethoscope. The traditional stethoscope is a device that has a horseshoe-shaped part that the doctor places around his or her forehead. This part is attached to a rigid rod and a bell shaped piece that is pushed slightly onto the belly.

Abnormal arterial sounds are often heard in a patient’s back, neck, stomach or groin. Any time an artery is partially blocked, it emits a vibration through the narrowed area called a “bruit”. A bruit is a whooshing sound heard as the blood squeezes through the narrowed area.