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Not to be confused with
or other types
Sonographer doing pediatric echocardiography
Echocardiogram in the parasternal long-axis view, showing a measurement of the heart's left ventricle
An echocardiogram, often referred to as a cardiac echo or simply an echo, is
a sonogram of the
heart. (It is not abbreviated as
ECG, because that is an abbreviation for an
Echocardiography uses standard two-dimensional, three-dimensional, and
to create images of the heart.
Echocardiography has become routinely used in the diagnosis, management, and follow-up of patients
with any suspected or known heart diseases. It is one of the most widely used diagnostic tests in
cardiology. It can provide a wealth of helpful information, including the size and shape of the heart
(internal chamber size quantification), pumping capacity, and the location and extent of any tissue
damage. An echocardiogram can also give physicians other estimates of heart function, such as a calculation
of the cardiac output,
and diastolic function (how
well the heart relaxes).
Echocardiography can help detect
cardiomyopathy, dilated cardiomyopathy, and many others. The use of stress echocardiography may
also help determine whether any chest pain or associated symptoms are related to heart disease. The
biggest advantage to echocardiography is that it is not invasive (does not involve breaking the skin
or entering body cavities) and has no known risks or side effects.
Not only can an echocardiogram create ultrasound images of heart structures, but it can also produce
accurate assessment of the blood flowing through the heart by Doppler echocardiography, using pulsed-
or continuous-wave Doppler ultrasound. This allows assessment of both normal and abnormal blood flow
through the heart. Color Doppler, as well as spectral Doppler, is used to visualize any abnormal
communications between the left and right sides of the heart, any leaking of blood through the valves
(valvular regurgitation), and estimate how well the valves open (or do not open in the case of valvular
stenosis). The Doppler technique can also be used for tissue motion and velocity measurement, by
Echocardiography was also the first ultrasound subspecialty to use intravenous contrast. (See
Echocardiography is performed by
cardiac physiologists (UK), or physicians trained in echocardiography.
Recognized as the “Father of Echocardiography”, the Swedish physician
Inge Edler (1911-2001), a
graduate of Lund University,
was the first of his profession to apply in diagnosing cardiac disease ultrasonic pulse echo imaging
technique, which the acoustical physicist
Floyd Firestone had developed
to detect defects in metal castings. In fact, Dr. Edler in 1953 produced the first echocardiographs
using an industrial Firestone-Sperry Ultrasonic Reflectoscope. In developing echocardiography, Edler
worked with the physicist
Carl Hellmuth Hertz,
the son of the Nobel laureate
Gustav Hertz and grandnephew
of Heinrich Rudolph
Health societies recommend the use of echocardiography for initial diagnosis when a change in
the patient's clinical status occurs and when new data from an echocardiogram would result in the
physician changing the patient's care.
Health societies do not recommend routine testing when the patient has no change in clinical status
or when a physician is unlikely to change care for the patient based on the results of testing.
A common example of overuse of echocardiography when not indicated is the use of routine testing
in response to a patient diagnosis of mild
valvular heart disease.
In this case, patients are often asymptomatic for years before the onset of deterioration and the
results of the echocardiogram would not result in a change in care without other change in clinical
A standard echocardiogram is also known as a transthoracic echocardiogram, or
cardiac ultrasound. In this case, the echocardiography transducer (or probe) is placed on the chest
wall (or thorax) of the
subject, and images are taken through the chest wall. This is a noninvasive, highly accurate, and
quick assessment of the overall health of the heart.
This is an alternative way to perform an echocardiogram. A specialized probe
containing an ultrasound transducer at its tip is passed into the patient's
esophagus. This allows image
and Doppler evaluation from a location directly behind the heart. This is known as a transœsophageal
echocardiogram. Transesophageal echocardiograms are most often used when transthoracic images are
suboptimal and when a more clear and precise image is needed for assessment. This test is performed
in the presence of a cardiologist, registered nurse, and ultrasound technician. Conscious sedation
and/or localized numbing medication may be used to make the patient more comfortable during the procedure.
Main article: Cardiac
A stress echocardiogram, also known as a stress echo, uses ultrasound imaging of
the heart to assess the wall motion in response to physical stress. First, images of the heart are
taken "at rest" to acquire a baseline of the patient's wall motion at a resting heart rate. The patient
then walks on a treadmill or uses another exercise modality to increase the heart rate to his or
her target heart rate, or 85% of the age-predicted maximum heart rate (220 − patient's age). Finally,
images of the heart are taken "at stress" to assess wall motion at the peak heart rate. A stress
echo assesses wall motion of the heart; it does not, however, create an image of the coronary arteries
directly. Ischemia of one or more coronary arteries could cause a wall motion abnormality which could
indicate coronary artery disease. The gold standard test to directly create an image of the coronary
arteries and directly assess for stenosis or occlusion is a cardiac catheterization. A stress echo
is not invasive and is performed in the presence of a licensed medical professional, such as a cardiologist,
and a cardiac sonographer.
Three-dimensional echocardiogram of a heart viewed from the apex
echocardiography (also known as four-dimensional echocardiography when the picture is moving) is
now possible, using a matrix array ultrasound probe and an appropriate processing system. This enables
detailed anatomical assessment of cardiac pathology, particularly valvular defects,
The ability to slice the virtual heart in infinite planes in an anatomically appropriate manner and
to reconstruct three-dimensional images of anatomic structures make it unique for the understanding
of the congenitally malformed heart.
Real-time three-dimensional echocardiography can be used to guide the location of
bioptomes during right ventricular
endomyocardial biopsies, placement of catheter-delivered valvular devices, and in many other intraoperative
3D Echo Box developed by the European Association of Echocardiography offers a complete review
of three-dimensional echocardiography.
Three-dimensional echocardiography technology may feature
anatomical intelligence, or the use of organ-modeling technology to automatically identify anatomy
based on generic models. All generic models refer to a dataset of anatomical information that uniquely
adapts to variability in patient anatomy to perform specific tasks. Built on feature recognition
and segmentation algorithms, this technology can provide patient-specific three-dimensional modeling
of the heart and other aspects of the anatomy, including the brain, lungs, liver, kidneys, rib cage,
and vertebral column.
Contrast echocardiography, or Contrast-enhanced ultrasound is the addition of ultrasound contrast
medium, or imaging agent, to traditional ultrasonography. The ultrasound contrast is made up of tiny
microbubbles filled with a gas core and protein shell. This allows the microbubbles to circulate
through the cardiovascular system and return the ultrasound waves creating a highly reflective image.
The most commonly used types of ultrasound contrast are known as: Definity® (definityimaging.com)
and Optison® (optisonimaging.com). Both have been approved by the FDA. There are multiple applications
in which contrast-enhanced ultrasound can be useful. The most commonly used application is in the
enhancement of LV endocardial borders for assessment of global and regional systolic function. Contrast
may also be used to enhance visualization of wall thickening during stress echocardiography, for
the assessment of LV thrombus, or for the assessment of other masses in the heart. Contrast echocardiography
has also been used to assess blood perfusion throughout myocardium in the case of coronary artery
The Contrast Echo Box developed by the European Association of Echocardiography, and the American
Society of Echocardiography
both offer a complete review of Contrast Echocardiography.