An echocardiogram, or "echo," is a heart ultrasound. The same technology used to image babies in pregnancy is used here to look at the heart in real time — the chambers, the valves, the walls, and the blood flowing through it. It is one of the most powerful, fastest, and safest cardiac investigations available.
If your doctor has asked for an echocardiogram, this guide explains what it shows, what happens during the scan, and how the different types differ.
Common Indications for an Echocardiogram
Your doctor may request an echocardiogram for:
- Investigating chest pain, palpitations, or unexplained shortness of breath.
- Evaluating a heart murmur heard on examination.
- Assessing the function of the heart after a heart attack.
- Following up known valve disease (mitral, aortic, tricuspid, or pulmonary).
- Looking for heart failure or assessing how well the heart is pumping.
- Screening for congenital heart disease in children or pregnancy.
- Monitoring patients on cardiotoxic chemotherapy.
What exactly does an echocardiogram show?
A standard echocardiogram shows:
- The size and shape of each heart chamber.
- The thickness and movement of the heart muscle walls.
- The four heart valves and how well they open and close.
- The direction and speed of blood flow (using Doppler).
- The fraction of blood pumped out with each beat (the ejection fraction).
- The pericardium — the sac around the heart — and any fluid within it.
It cannot show the coronary arteries themselves; that needs a CT or invasive angiogram.
What are the types of echocardiograms?
Several types exist, depending on what your doctor needs to see:
- Transthoracic echocardiogram (TTE) — the standard test, done by placing the probe on the chest. Painless and non-invasive.
- Transoesophageal echocardiogram (TOE/TEE) — the probe is passed down the food pipe to get a much closer view of the heart valves and back of the heart. Done under sedation.
- Stress echocardiogram — performed before and immediately after exercise (or a medication that mimics exercise) to see how the heart performs under load.
- Foetal echocardiogram — performed during pregnancy to look at a baby's heart, usually between 18 and 24 weeks.
The standard TTE is the test most patients have unless a specific question requires one of the others.
What happens during a transthoracic echocardiogram?
- You undress from the waist up and put on a gown.
- You lie on the exam table, usually turned slightly onto your left side.
- A few electrodes (sticky pads) are attached to your chest to record the heartbeat alongside the images.
- Warm gel is applied to the chest, and the sonographer or cardiologist glides the probe over your chest — at the breastbone, under the rib cage, and at the side.
- You may be asked to hold your breath briefly or to roll further onto your side at certain points.
- The whole scan typically takes 20 to 45 minutes.
Do I need to prepare for an echocardiogram?
For a standard TTE:
- No fasting is required.
- Wear a two-piece outfit so you only need to remove your top.
- Avoid heavy lotions or oils on your chest on the day of the test.
For a TOE: you will be asked to fast for 4 to 6 hours beforehand because of the sedation, and you will need someone to drive you home.
For a stress echo: wear comfortable clothes and trainers, and skip caffeine for 6 hours before the test.
Will the test be painful?
A transthoracic echocardiogram is painless. The probe is firm and the sonographer may press more firmly under your rib cage to get certain views — this can be briefly uncomfortable but should not hurt. Tell the sonographer if it does.
A TOE involves swallowing a probe under sedation. Most patients have no memory of the procedure and only mild throat soreness afterward.
How long do the results take?
In Nigerian centres, a cardiologist or specialist sonographer often reviews the images immediately and may give you preliminary feedback at the end of the scan. The formal written report usually reaches your doctor within 24 to 72 hours.
Is an echocardiogram safe?
Radiation-free, contrast-rarely-used
A standard echocardiogram uses sound waves only — no radiation. Contrast bubbles are occasionally used to improve image quality in patients whose heart is hard to see, but for most patients no contrast is needed. The test is safe in pregnancy and at any age.
What if my echocardiogram finds something abnormal?
Common findings range from mild (small valve leaks that don't need treatment) to significant (severely reduced pumping function, severe valve narrowing). Your doctor will combine the echo result with your symptoms, blood tests, and ECG to decide next steps — which may include medication adjustment, further imaging (cardiac MRI or CT), or referral to a cardiologist for procedural treatment.
When should I seek emergency care?
Ongoing chest pressure, severe breathlessness, fainting, blue lips, or a new sustained rapid or irregular heartbeat needs emergency assessment. A routine echocardiogram should not delay ECG, blood tests, and acute treatment, and a normal echo does not rule out a heart attack or every rhythm problem.
What are the important limitations?
Ultrasound does not use ionising radiation, but a useful result still depends on the clinical question, the operator, the equipment, patient anatomy, and whether the target can be reached by sound waves. Gas, bone, body habitus, pain, movement, and a limited acoustic window can hide disease. A normal scan does not automatically exclude the suspected condition; persistent or worsening symptoms need clinical reassessment and sometimes repeat ultrasound, CT, MRI, laboratory tests, or another specialist test.
Ultrasound should be used for a medical purpose, with output and examination time kept as low as reasonably achievable—especially in pregnancy and with Doppler. Internal scans and procedures require explanation, consent, privacy, and a chaperone according to patient preference and local policy.
Sources and further reading
Conclusion
An echocardiogram is a fast, radiation-free, highly informative way to look at the heart. It is the first imaging test for nearly every cardiac concern — chest pain, breathlessness, palpitations, murmurs — and it is comfortable enough to repeat as often as needed for monitoring. If your doctor recommends one, it is among the lowest-risk, highest-information tests in medicine.