E–G

echocardiogram A noninvasive, diagnostic
ULTRASOUND examination of the HEART that can
show the heart’s structure and, when combined
with Doppler technology, the flow of BLOOD
through the heart’s chambers and the CORONARY
ARTERIES. Echocardiogram is most effective for
evaluating VALVULAR HEART DISEASEand structural
malformations of the heart such as major congeni-
tal deformities, septal defects, and patent ductus
arteriosus (PDA).
There is no preparation for a echocardiogram,
which uses soundwaves to create visual images.
For a transthoracic echocardiogram (TTE), the
ultrasonographer places a small amount of gel on
the SKINof the chest to improve contact with the
transducer, the device that sends and receives the
sound signals. The ultrasonographer then moves
the transducer over the surface of the skin. For a
transesophageal echocardiogram (TEE), the ultra-
sonographer numbs the back of the THROATand
passes a narrow cable with a transducer at the tip
down the throat into the ESOPHAGUS. A TEE places
the transducer as close as possible to the heart,
usually to obtain specific images such as to detect
septal defects or certain valve malformations.
A computer converts the sound signals into
two- or three-dimensional images. Typically the
cardiologist does an ELECTROCARDIOGRAM (ECG)at
the same time, to correlate the visual images from
the echocardiogram with the heart’s electrical
activity. Sometimes the cardiologist will combine
the echocardiogram with an injection of dye,
administered intravenously, to better highlight the
inner structures of the heart. Echocardiogram or
TTE takes 10 to 20 minutes and there is no recov-
ery time necessary after the procedure. People
undergoing TEE generally receive sedation before
the procedure begins so go to a recovery area after

the TEE until fully awake from the sedative and

the cardiologist is satisfied there will be no adverse

effects.

CONDITIONS ECHOCARDIOGRAM CAN HELP

DIAGNOSE OR MONITOR

AMYLOIDOSIS aorticANEURYSM

AORTIC STENOSIS CARDIAC TAMPONADE

CARDIOMYOPATHY congenital heart malformations

ENDOCARDITIS HEART FAILURE

HEMACHROMATOSIS mitral valve prolapse

MYOCARDIAL INFARCTION MYOCARDITIS

MYXOMA patent ductus arteriosus

PERICARDITIS PRIMARY PULMONARY HYPERTENSION

septal defect VALVULAR HEART DISEASE

See also ANGIOGRAM; COMPUTED TOMOGRAPHY(CT)

SCAN; CONGENITAL HEART DISEASE; MAGNETIC RESO-

NANCE IMAGING(MRI).

ectopic beat An extra or additional heartbeat.

Ectopic beats can be atrial, called premature atrial

contractions (PACs), or ventricular, called prema-

ture ventricular contractions (PVCs). PACs are

nearly always benign (do not require treatment).

Though most PVCs are also benign, persistent

PVCs can cause symptoms that do require treat-

ment. CAFFEINE is a common cause of ectopic

beats. ALCOHOLuse, cigarette smoking, and illicit

drugs also can cause or exacerbate ectopic beats.

The most common symptom of ectopic beat is

PALPITATIONS, the perception of the heart jumping

or skipping a beat though it actually does neither.

Ectopic beats are premature—that is, they are nor-

mal contractions that occur before their normal

rhythm in the CARDIAC CYCLE. The beat that fol-

lows, also a normal beat, then feels intensified. An

ELECTROCARDIOGRAM(ECG) shows the heart’s electri-

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