What is an Echocardiogram and What Does it Show? 

If a doctor suspects a problem with your heart perhaps after hearing a murmur through a stethoscope the most important test they will order is an echocardiogram. Often referred to simply as an ‘echo’, this test is a type of ultrasound scan used to look at the heart and nearby blood vessels. It is non-invasive, does not use radiation, and provides a real-time, moving image of the heart in action. It is the ‘gold standard’ for diagnosing heart valve disease and assessing overall heart function. This article explains what the test involves and the vital information it provides to your medical team. 

What We’ll Discuss in This Article 

• The clinical definition of an echocardiogram and how it uses ultrasound technology. 

• The different types of echocardiograms performed in the UK. 

• Exactly what the scan reveals about heart valves and chambers. 

• How the test measures heart efficiency, including ‘ejection fraction’. 

• The role of an echocardiogram in diagnosing heart valve disease. 

• Safety information and what to expect during the procedure. 

How an Echocardiogram Visualises the Heart? 

An echocardiogram is a diagnostic test that uses high-frequency sound waves (ultrasound) to create live, moving images of the heart. During the procedure, a small probe called a transducer is moved over the chest. It sends out sound waves that bounce off the heart structures and return to the probe, where they are converted into pictures on a monitor. This allows healthcare professionals to see the heart beating and pumping blood in real-time. 

In the UK, this is the most common imaging test for heart disease because it is safe, painless, and highly detailed. It allows doctors to assess the heart’s anatomy without the need for surgery or exposure to X-rays. 

• Transthoracic Echo (TTE): The standard version where the probe is placed on the skin of the chest. 

• Non-Invasive: There are no needles or radiation involved in a standard echo. 

• Real-Time Imaging: Doctors can see the valves opening and closing as the heart beats. 

• Doppler Ultrasound: A specific setting that shows the speed and direction of blood flow. 

What Does an Echocardiogram Show? 

An echocardiogram shows the physical structure and functional capacity of the heart. It reveals the size and thickness of the heart chambers, the movement of the heart walls, and the precise functioning of the four heart valves. By using ‘Doppler’ technology, the scan also shows if blood is flowing in the correct direction and at the correct pressure, helping to identify any leaks or blockages. 

The images provided by an echo are so detailed that a cardiologist can measure the heart to within a millimetre. This is essential for tracking how a condition progresses over time. 

• Valve Function: Shows if valves are opening fully (checking for stenosis) or closing tightly (checking for regurgitation). 

• Chamber Size: Identifies if the heart is enlarged (dilation) or if the muscle is too thick (hypertrophy). 

• Pumping Strength: Calculates the ‘Ejection Fraction’ (EF), which is the percentage of blood pumped out of the main chamber with each beat. 

• Congenital Defects: Identifies holes in the heart or abnormally shaped valves present from birth. 

What Causes a Doctor to Order an Echocardiogram? 

A doctor will order an echocardiogram to investigate symptoms or clinical signs that suggest the heart is not working perfectly. The most common cause is the discovery of a heart murmur. Other reasons include investigating the cause of persistent breathlessness, chest pain, or unexplained swelling in the legs. It is also used to assess damage after a heart attack or to monitor known valve conditions. 

Identifying Valve Disease 

If a GP hears a ‘whooshing’ sound (murmur), the echo confirms which valve is affected. It can distinguish between a valve that is too stiff (calcified) and one that is too ‘floppy’ (prolapsed). 

Assessing Heart Failure 

For patients with heart failure, the echo is vital to see how well the heart is pumping. If the ‘Ejection Fraction’ is low, it helps doctors decide which medications or treatments are necessary. 

Detecting Blood Clots or Fluid 

The scan can identify fluid buildup around the heart (pericardial effusion) or blood clots inside the heart chambers, which could increase the risk of a stroke. 

What are the Triggers for Different Types of Echo? 

While the standard chest-surface echo (TTE) is most common, certain ‘triggers’ may require more specialised versions. If the standard images are not clear enough perhaps due to lung disease or body shape a doctor may order a ‘Transoesophageal Echo’ (TOE). Other triggers, like needing to see how the heart behaves under stress, will lead to a ‘Stress Echocardiogram’. 

• Transoesophageal Echo (TOE): A small probe is passed down the gullet (oesophagus) to get a much closer view of the heart from behind. 

• Stress Echo: Images are taken while the heart is beating fast, either due to exercise on a treadmill or medication that mimics exercise. 

• Bubble Study: Saline (saltwater) with tiny bubbles is injected into a vein to check for small holes between the heart chambers. 

Differentiation: ECG vs. Echocardiogram 

It is important to differentiate between an Electrocardiogram (ECG) and an Echocardiogram. An ECG records the ‘electrical’ activity of the heart (the rhythm), while an Echocardiogram shows the ‘mechanical’ structure and movement (the pump). While both are used to check heart health, they provide completely different types of information and are often used together for a full assessment. 

Feature	Electrocardiogram (ECG)	Echocardiogram (Echo)
Primary Focus	Electrical rhythm and timing.	Physical structure and blood flow.
Technology	Sticky pads (electrodes) on the skin.	Ultrasound probe and gel.
What it Detects	Arrhythmias, heart rate, heart attacks.	Valve disease, heart failure, holes in the heart.
Visual Output	A graph of wavy lines.	A moving video of the heart.

Conclusion 

An echocardiogram is a vital, non-invasive diagnostic tool that provides a clear window into the workings of your heart. By showing the structure of the valves, the size of the chambers, and the strength of the heart’s pump, it allows for the accurate diagnosis and management of various cardiac conditions. Whether used to investigate a heart murmur or monitor heart failure, it is the most effective way to ensure your heart is functioning safely. 

If you experience severe, sudden, or worsening symptoms, such as intense chest pain, sudden breathlessness, or fainting, call 999 immediately. 

Authority Snapshot (E-E-A-T Block) 

This article has been reviewed by Dr. Stefan Petrov, a UK-trained physician with extensive experience in general medicine, surgery, and intensive care. Drawing on his clinical background in performing diagnostic procedures and managing cardiac patients in hospital wards, this guide provides a medically accurate overview of echocardiography. Our goal is to provide safe, factual, and clear information based on NHS and NICE standards to help you understand this essential heart imaging test.