Definition and Overview
An echocardiogram is an imaging procedure that uses sound waves to produce a sonogram of the heart. The resulting images are comparatively more detailed than a standard x-ray, making it an essential tool for the accurate diagnosis of various heart conditions. An echocardiogram is also instrumental in designing an effective and efficient treatment, monitoring, and management plan for patients with existing heart condition.
As a standard diagnostic procedure used in the field of cardiology, an echocardiogram reveals a wealth of information about the patient's heart. The resulting images show the organ's structural aspects, including its shape and size. With this, it would be easy to diagnose conditions that involve altered or abnormal shapes and sizes of the human heart. Damage in the cardiac tissues can also be seen, including the exact location of the damage and its extent. The heart's performance can also be measured by an echocardiogram through cardiac output, the fractions of blood ejections, and its diastolic functions.
Traditionally, a standard two-dimensional echocardiogram was used in this procedure. In this test, the resulting images display a cross sectional slice of the beating heart including major blood vessels, chambers, and valves. In the last decade, 3-dimensional imaging technology was introduced, which offers a more accurate and comprehensive views of congenital abnormalities as well as cardiac valves, making it very useful in diagnosing different types of heart diseases. Cardiomyopathy, a term that refers to various conditions involving measurable deterioration of cardiac muscles, is just one of the heart diseases that this diagnostic procedure can detect. By revealing heart structures, affected muscles, and the extent of their deterioration, various heart conditions can be easily tracked by this procedure.
Types of Echocardiogram
- Transthoracic echocardiogram, or TTE , is one of the most common types of echocardiogram, and is typically the standard test performed on patients who are complaining of symptoms related to various heart diseases. The technician produces images of the heart by moving a transducer along the abdominal wall and chest area.
- Stress echocardiogram. This is typically performed to determine the cause of chest pains and other related symptoms, or to confirm decreased blood flow to the heart (an effect of coronary artery disease). This type of test is performed at two different times: while the patient is relaxed and after performing an activity like running on a treadmill so the diagnosing physician can make a comparison on how the heart functions in different scenarios.
- Transesophageal echocardiogram. This uses a probe, which is passed down the throat instead of being held against the chest or abdominal wall from the outside. This diagnostic test produces clearer images of the heart and is performed under local anaesthesia to reduce discomfort.
- Doppler echocardiogram. This test is performed to assess the blood flow based on its velocity and direction as it moves along the valves, blood vessels, and chambers of the heart.
Echocardiography is performed by trained professionals known as cardiac sonographers; doctors trained in this diagnostic procedure can also operate the echocardiogram machine.
Who should undergo and expected results
After a certain age, physicians typically recommend this diagnostic procedure to their patients as part of an annual physical check-up as a preventative measure or to catch any heart condition during its early stages. It is also prescribed to patients who are considered high risk of developing cardiac problems.
The test is also for patients who have an existing heart disease and is performed as part of their treatment programme. The resulting images are typically used by their physicians to monitor the progress and effectiveness of treatment and when deciding if the treatment programme must be revised to achieve optimum results. Patients who display symptoms related to heart diseases such as shortness of breath, inexplicable pressure or pain in the chest, and irregular heartbeats must also undergo the procedure the soonest possible time.
A normal echocardiogram means that there are no abnormalities in the heart's structure and performance. However, if the test came back with an abnormal result, the diagnosing physician will typically request more tests to make an accurate diagnosis.
How the procedure works
Most types of echocardiograms do not require much preparation. Stress echocardiograms require patients to eat lightly before the test, and wear comfortable shoes and light clothes. A transesophageal echocardiogram, on the other hand, requires a patient to refrain from eating or drinking around six hours before the procedure.
This diagnostic procedure is typically performed in a doctor's office, a clinic, or a hospital. If the patient cannot make it to any of those places because he or she is incapacitated, the procedure can be performed at the hospital bedside.
Before the procedure, the patient will be advised to remove clothes, jewellery, and other accessories above the waist, which can interfere with the sound waves.
Depending on the type of echocardiogram, a transducer can be used and moved around the patient's chest or abdominal wall. In the case of a transesophageal cardiogram, the internal structures and details of the heart will be observed through a probe, which is inserted into the patient's throat.
Possible risks and complications
Echocardiograms are safe in general, as they are mostly non-invasive and use only safe sound waves to look into the heart's structures and performance. However, some kinds of echocardiograms use a contrasting agent, which might cause allergic reactions in some people.
A transesophageal echocardiogram is more invasive than any other kind of diagnostic procedure under this category. People who recently had radiotherapy to the chest or neck should not undergo this procedure, as well as people who have issues with their oesophagus (having abnormally narrow throats, engorged veins, or severe neck arthritis). Some patients might also experience difficulty in swallowing after the procedure.
Known complications or side effects of TEE include minor bleeding in the throat or mouth, discomfort, nausea, difficulty in breathing (caused by the probe being inserted into the throat), and slow or irregular heartbeats. The probe can also tear the oesophagus, but this occurrence is quite rare.
Stress echocardiogram involves a certain activity or medication that can make the heart beat faster and harder. This means that both the patient and physician should look out for possible complications such as low blood pressure, dizziness, nausea, shortness of breath, irregular heartbeats, or even a possible heart attack.
- Connolly HM, Oh JK. Echocardiography. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 15.