What is an Echocardiogram?
An echocardiogram is a test utilising sound waves to create a moving picture of the heart. This allows the doctor to evaluate how well the heart is beating and pumping blood, helping determine whether any abnormalities in the heart muscle or heart valves are present, as well as assessing risk for heart disease.
Who needs an Echocardiogram?
If a doctor suspects abnormalities with the valves or chambers of their patient's heart, or its ability to pump, they may suggest an echocardiogram. An echocardiogram can also be used to detect congenital heart defects in unborn babies.
The different types of echocardiograms include:
- Transthoracic echocardiogram – this is the most common, non-invasive echocardiogram. A sonographer spreads gel over the chest and moves a transducer to different locations on the chest or abdominal wall. The transducer records the sound wave echoes that the heart produces. These waves are converted by a computer into moving images on a monitor.
- Stress echocardiogram – this involves an echocardiogram both before and after the heart is stressed through exercise or by injecting a medicine that makes the heart beat harder and faster. This test is usually conducted to assess whether decreased blood flow to the heart is present.
- Transesophageal echocardiogram – this test is generally recommended when it is difficult to get clear images of the heart with a standard echocardiogram. A probe is passed down the oesophagus instead of being moved over the outside of the chest wall. Clearer pictures of the heart are produced as the probe is located closer to the heart and because the lungs and bones of the chest wall do not block the sound waves produced by the probe. A sedative and anaesthetic applied to the throat are used to make the test more comfortable.
- Doppler echocardiogram – this test is used to see how blood flows through the heart chambers, heart valves and blood vessels. The movement of the blood reflects sound waves to a transducer. The ultrasound computer then measures the direction and speed of the blood flowing through the heart and blood vessels. Doppler techniques are commonly used for transthoracic and transeophageal echocardiograms.
What needs to be brought to the appointment?
Patients will need to bring their Medicare card to the appointment. For a stress echocardiogram, patients need to bring comfortable walking/running shoes as well as loose/exercise clothing.
What are the risks?
The risks associated with a standard transthoracic echocardiogram are minimal. Some discomfort may be felt when the electrodes (similar to an adhesive bandage) attached to the body are removed.
For transesophageal echocardiogram, some soreness in the throat may be experienced a few hours afterwards. Oxygen levels may be monitored during the test to check for any breathing problems caused by the sedative medication.
For stress echocardiograms, either the exercise or medication may temporarily cause an irregular heartbeat. It is rare for serious complications to occur as a result.
What will the test feel like?
Patients are required to disrobe from the waist up and lie on an examination table or bed on their back. Electrodes are then placed on the body to help detect and conduct the electrical currents of the heart.
For a tranesophageal echocardiogram, a sedative is provided to help patients relax, and a spray or gel is used to numb the throat.
To view the images better, the technician will dim the lights. A “whooshing” sound may be heard throughout the test. This is the machine recording the blood flowing throughout the heart.
The test generally takes less than an hour, but this can vary depending on each patient's condition. For transthoracic echocardiograms, patients may be asked to breathe in a certain way or to roll onto their left side. At times the transducer may be held uncomfortably firmly against the chest. This is sometimes necessary to produce the best images of the heart.
What happens after the procedure?
If the test results are normal, no further testing may be needed. If the results are of concern, patients may be referred to a cardiologist for further assessment. Treatment will vary, depending on what is found during the exam and the specific signs and symptoms. Sometimes the doctor may suggest a repeat echocardiogram after several months.
The results of the echocardiogram can reveal many aspects of heart health including:
- Heart size: weakened or damaged heart valves, high blood pressure, or other diseases can cause heart chambers to enlarge. An echocardiogram can be used to determine the need for treatment, or to monitor treatment effectiveness.
- Pumping strength: the echocardiogram can help determine heart pumping strength. Specific measurements may include the percentage of blood that’s pumped out of a filled ventricle with each heartbeat (ejection fraction) or the volume of blood pumped by the heart in one minute (cardiac output). If insufficient blood is being pumped around the body, there is a risk of heart failure.
- Heart muscle damage: the echocardiogram can also help determine whether all parts of the heart wall are contributing equally to the pumping activity. Weakness can occur as a result of a heart attack or due to insufficient oxygen. It may also indicate coronary artery disease or various other conditions.
- Valve problems: the echocardiogram can show how heart valves move during beats. This can help determine whether the valves open wide enough for adequate blood flow, or close fully to prevent blood leakage. Abnormal blood flow patterns and conditions such as aortic valve stenosis — when the heart's aortic valve is narrowed — can be detected as well.
- Heart defects: an echocardiogram can detect many types of heart defects, such as heart chamber problems, abnormal connections between the heart and major blood vessels, and complex heart defects that are present at birth. Echocardiograms can even be used for monitoring a baby’s heart development before birth.