What is the Difference Between an ECG and an Echo?

So What are the Differences Between these Two Tests?

If you’ve recently been referred for heart tests, or you're researching heart health for yourself or a family member, you might be wondering — what is the difference between an ECG and an echo? It’s a really common question I get asked here at Heartsure all the time!

Both tests are extremely useful in cardiology — and while they sound similar, they do very different things. I’ll explain what an ECG is, what an echocardiogram is, why they’re used, and how they work together to provide a full picture of your heart health.

Why Are Heart Tests Important?

Heart disease remains one of the leading causes of illness and death in the UK. According to the British Heart Foundation, around 7.6 million people in the UK live with heart or circulatory diseases.

Many heart conditions don’t cause obvious symptoms in the early stages — but the good news is that modern heart tests like the ECG and echo allow us to pick up problems early, often before they become serious.

These tests are non-invasive, quick, and can provide essential information to guide diagnosis and treatment.

What is an ECG?

An ECG stands for electrocardiogram. It’s a simple test that records the electrical activity of your heart. Every time your heart beats, it sends electrical signals through its muscle, telling it when to contract and relax.

An ECG captures these signals and displays them as a graph — allowing us to see whether the heart's rhythm is normal, too fast, too slow, or irregular.

What Does an ECG Show?

An ECG is particularly good at detecting:

• Arrhythmias – irregular heart rhythms like atrial fibrillation

• Slow heart rates (bradycardia)

• Fast heart rates (tachycardia)

• Evidence of previous heart attacks

• Some signs of poor blood flow (ischaemia)

It's a very quick test — taking just a few minutes — and is completely painless.

What Happens During an ECG?

At Heartsure in Surrey, we perform 12-lead ECGs routinely.

Here’s what you can expect:

1. You’ll lie on an examination couch.

2. Small sticky electrode pads are placed on your chest, arms and legs.

3. These are connected to a machine which records the heart’s electrical signals.

4. The machine prints out a tracing for the cardiologist to interpret.

There’s no need to fast or avoid drinks beforehand. You can go home straight after the test.

What is an Echocardiogram?

An echocardiogram (often called an 'echo') is completely different to an ECG.

It’s an ultrasound scan of the heart — similar to the scans used during pregnancy — which allows us to see the heart's structure and function in real time.

While the ECG looks at the heart's electrical activity, the echo looks at its physical performance — how well the heart muscle is pumping, whether the valves are working properly, and whether there are any structural problems.

What Does an Echocardiogram Show?

An echocardiogram can detect:

• Heart failure – where the heart doesn’t pump effectively

• Valve disease – such as leaking or narrowed valves

• Cardiomyopathy – thickened or weakened heart muscle

• Fluid around the heart (pericardial effusion)

• Structural problems such as congenital defects

• Impact of previous heart attacks on heart function

What Happens During an Echocardiogram?

An echo usually takes between 20-40 minutes.

Here’s what to expect:

1. You’ll lie on an examination couch.

2. A small ultrasound probe is moved across your chest, using a water-based gel to help conduct sound waves.

3. The probe sends sound waves into the chest, which bounce back to create images of the heart.

4. The cardiologist can watch the heart beating in real time.

It’s painless — although you may feel a little pressure from the probe. No radiation is used.

Key Differences Between ECG and Echocardiogram

Do I Need Both Tests?

Often — yes.

Many heart conditions require both an ECG and an echocardiogram to reach a full diagnosis.

For example:

• A patient with palpitations might have an ECG to check their rhythm — and then an echo to ensure the heart muscle is normal.

• A patient with breathlessness might have an ECG to look for signs of strain — and then an echo to see if the heart is pumping effectively.

They are complementary tests — providing different but equally important information.

When Might a Cardiologist Recommend These Tests?

At Heartsure, we might recommend an ECG and/or echo if you’re experiencing:

• Chest pain or discomfort

• Shortness of breath

• Palpitations or irregular heartbeats

• Dizziness or fainting

• Swelling in the legs or ankles

• New heart murmurs detected by your GP

• Known high blood pressure or raised cholesterol

They’re also commonly used for patients with risk factors like diabetes, family history of heart disease, or those needing pre-operative heart checks.

Are There Any Risks?

Both ECGs and echocardiograms are completely safe. So, no there isn't!

Neither test involves radiation, injections, or sedation. You can return to your normal activities straight after the test.

Why Choose a Private Cardiologist in Surrey for These Tests?

At Heartsure, we offer fast access to ECG and echocardiography in our Surrey clinic — without long waiting lists.

Benefits include:

• Same-week appointments

• Consultant-led interpretation

• Personalised treatment plans

• On-site testing for convenience

• Follow-up advice and care

If you’d like to book an assessment, contact us here and our team will guide you through the process.

To Conclude

So, what is the difference between an ECG and an echo?

In short:

• An ECG looks at the electrical activity of your heart.

• An echocardiogram looks at the structure and function of your heart.

Both tests are non-invasive, quick, and extremely useful for diagnosing heart conditions or providing reassurance if you’re concerned.

At Heartsure, we’re proud to provide expert cardiology care from our Surrey clinic — combining advanced testing with personalised patient support.

If you’re experiencing symptoms — or simply want peace of mind about your heart health — don’t hesitate to contact us here to arrange a consultation using our online tool.