Heart Ultrasound: Uses and Results

A heart ultrasound, known medically as an echocardiogram, uses harmless sound waves to build a moving picture of your beating heart. It is one of the most common cardiac tests because it is painless, involves no radiation, and shows the heart's chambers, valves, and pumping action in real time. This guide explains why the test is ordered, how it is done, and how to think about the results, though only your own clinician can interpret what a scan means for you.

What a heart ultrasound actually is

An echocardiogram is an ultrasound scan focused on the heart. A small handheld device called a transducer sends high-frequency sound waves into the chest. Those waves bounce off the heart's structures and return as echoes, and a computer turns the echoes into live images on a screen. Because the picture moves in real time, a cardiologist can watch the valves flapping and the muscle squeezing with each beat.

As the MedlinePlus medical encyclopedia explains, an echocardiogram is a test that uses sound waves to create pictures of the heart, including the chambers, the valves, and the sac around the heart called the pericardium. It is a specific application of the same technology described in our general overview of how ultrasound works.

Why doctors order an echocardiogram

Your clinician may request a heart ultrasound to investigate symptoms, to confirm or monitor a known condition, or to check how the heart is coping with another illness. Common reasons include:

• Shortness of breath, chest discomfort, palpitations, dizziness, or swelling in the legs that may point to a heart problem.
• A heart murmur heard through a stethoscope, which can signal a valve issue.
• Assessing the pumping strength of the heart, often reported as the ejection fraction, in people with suspected or known heart failure.
• Looking for damage after a heart attack, or for congenital differences present from birth.
• Checking for fluid around the heart, blood clots, or the effect of high blood pressure over time.

The test is descriptive rather than a cure. It gives the care team a detailed map so they can decide whether further tests, medication, or referral are needed. Because heart symptoms can overlap with other conditions, your doctor may also consider imaging such as a CT scan or a broader radiology work-up depending on your situation.

The main types of heart ultrasound

There is no single echocardiogram. The right version depends on what the doctor needs to see. According to the NHS, the common types are:

• Transthoracic echocardiogram (TTE): the standard test, performed by moving the transducer across the outside of the chest. It is painless and needs no recovery time.
• Transoesophageal echocardiogram (TOE or TEE): a thin probe is passed down the food pipe to sit close behind the heart, giving clearer views of the valves and back chambers. It is not painful but can feel uncomfortable, and the throat is usually numbed with a mild sedative offered.
• Stress echocardiogram: images are taken before and after the heart is stressed with exercise or medication, to reveal problems that only appear when the heart works harder.
• Doppler and colour Doppler: not a separate appointment but an added technique that shows the speed and direction of blood flow, which helps grade leaky or narrowed valves.

How the scan is performed step by step

A standard transthoracic scan is straightforward. Knowing the sequence can ease any nerves.

1. You undress from the waist up and lie on your left side on an examination couch.
2. Small sticky electrodes are placed on your chest to record the heartbeat alongside the images.
3. A water-based gel is applied to your skin. The gel removes air between the probe and the body so the sound waves can pass through cleanly.
4. The sonographer moves the transducer across your chest, pressing gently and angling it to capture different views. You may be asked to hold your breath briefly or change position.
5. You might hear a whooshing sound, which is the Doppler recording of blood flow. This is normal.

How to prepare

For a routine transthoracic echocardiogram there is usually little to do. You can normally eat, drink, and take your regular medicines as usual, and wearing a two-piece outfit makes changing easier. Preparation differs for the other types:

• Transoesophageal: you will typically be asked not to eat or drink for several hours beforehand, and to arrange a lift home if a sedative is used.
• Stress echocardiogram: wear comfortable clothing and shoes suitable for exercise, and follow any instructions about pausing certain heart medicines, which your clinician will confirm.

Always follow the specific instructions from the department that booked your test, because protocols vary between clinics and countries. If you are unsure where to have the scan, our guide to finding an ultrasound clinic near you covers what to look for.

How it compares with other heart tests

A heart ultrasound is often one part of a wider assessment rather than a stand-alone answer. It is helpful to understand where it fits among the common tests, because each looks at the heart in a different way:

• Electrocardiogram (ECG): records the heart's electrical activity as a trace. It is quick and useful for rhythm and signs of strain, but it does not show the heart's structure the way an echocardiogram does.
• Echocardiogram: shows structure and movement, including chamber size, valve function, and pumping strength, all without radiation.
• Cardiac CT: gives detailed images of the coronary arteries and uses X-rays, so it involves radiation. Our overview of the CT scan explains how that works.
• Cardiac MRI: provides very detailed tissue images using magnets rather than radiation, and is often reserved for specific questions.

Because these tests answer different questions, your doctor chooses among them based on your symptoms and history. A heart ultrasound is frequently the first structural test because it is safe, quick, and widely available, and it can be part of a broader radiology assessment when needed.

Is a heart ultrasound safe?

Yes. Diagnostic ultrasound uses sound waves rather than ionising radiation, which is a key reason it is used so widely, including in pregnancy and in children. The RadiologyInfo resource from the Radiological Society of North America and the American College of Radiology notes that ultrasound is safe, noninvasive, and does not use radiation. A transthoracic echocardiogram has no known harmful effects and can be repeated as often as your care needs. The transoesophageal version carries small risks linked to passing the probe and any sedation, which the team will discuss and consent with you beforehand.

What the results can and cannot tell you

An echocardiogram produces measurements such as chamber sizes, wall thickness, valve function, and the ejection fraction, along with images the cardiologist reviews. These numbers only have meaning in the context of your symptoms, history, and other tests. A value slightly outside a reference range is not automatically a problem, and a normal scan does not rule out every heart condition.

This is why interpretation belongs to a qualified clinician. Reading your own report can cause needless worry or false reassurance. If you have been given results, bring your questions to the doctor who ordered the test.

Frequently asked questions

Does a heart ultrasound hurt?

A standard transthoracic echocardiogram is painless. You may feel the coolness of the gel and firm pressure from the probe, but it should not hurt. A transoesophageal echocardiogram is not painful either, though some people find the probe in the throat uncomfortable, which is why the throat is numbed and a sedative is often offered.

How long does the test take?

A routine transthoracic scan usually takes about 30 to 60 minutes, including preparation. Stress and transoesophageal studies can take a little longer because of the extra steps involved.

Is there any radiation with an echocardiogram?

No. A heart ultrasound uses sound waves, not radiation, so there is no radiation exposure. This is one reason it is favoured for repeated monitoring and for use in pregnancy and children.

Do I need to fast before a heart ultrasound?

For a standard transthoracic scan you generally do not need to fast and can take your usual medicines. Fasting is commonly required before a transoesophageal echocardiogram. Follow the exact instructions from the department that booked your appointment.

When will I get my results?

The images are reviewed by a cardiologist, and the timing of results varies by clinic. Sometimes findings are available soon after, and sometimes a follow-up appointment is arranged. Your referring clinician will explain what the results mean for you.