Tests & diagnostics
ECG explained
A plain-English guide to the resting electrocardiogram (ECG) - what the tracing shows, how to prepare and what happens next if it is abnormal.
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At a glance
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Preparation
No special preparation is needed; avoid oily skin creams on the chest and wear clothing that is easy to remove from the waist up.
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What happens during the test
Small sticky electrodes are placed on your chest, arms and legs while you lie still for a few minutes; the recording itself takes under a minute and is completely painless.
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Results timeline
A private resting ECG is usually reported the same day, often with an immediate verbal summary from the clinician.
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Specialist follow-up
Abnormal or borderline findings are reviewed by a consultant cardiologist, who may suggest an echocardiogram, ambulatory monitoring or blood tests.
What this test is and when it is recommended
A resting electrocardiogram records the electrical activity of your heart from the skin surface. It shows the heart rhythm, the rate, and patterns that can point to previous heart attacks, thickened heart muscle, or problems with electrical conduction. It is often the first test recommended when you have palpitations, chest discomfort, breathlessness or an irregular pulse, and it forms part of most private health assessments.
How to access it
A resting ECG can be arranged through a GP referral or booked directly as a self-pay test at most private cardiology clinics. NHS waiting lists for diagnostics are often long, while private appointments are typically available within days to around two weeks. Costs vary by provider.
Frequently asked
Common questions about ECG explained.
Quick, plain-English answers to what people ask us most.
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What is ECG explained and what does it show?
ECG explained is an imaging or diagnostic procedure that allows doctors to look at the relevant part of the body in detail, helping to identify or rule out specific problems. It gives information that usually can't be obtained from a physical examination or blood test alone. The findings are interpreted alongside your symptoms and medical history.
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Why might a doctor request it?
It's usually requested to investigate specific symptoms, follow up on a previous finding, or check on a known condition. It may also form part of a wider screening or health assessment package. Your doctor will explain what they're hoping to see or rule out before referring you.
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Do I need to prepare beforehand?
Preparation varies — some procedures require fasting, a full or empty bladder, stopping certain medications, or avoiding specific products beforehand, while others need no preparation at all. Because requirements are specific to this exact procedure, always follow the instructions given by the clinic at booking rather than assuming. Arriving properly prepared reduces the chance of the appointment needing to be rescheduled.
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What happens during the procedure?
You'll usually be guided through each step by trained staff, and most of these procedures are performed with you either lying still, seated, or in a specific position for a short period. Depending on the exact test, it may take anywhere from a few minutes to around an hour. Staff will explain what to expect and answer any questions before you begin.
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Is it painful, and are there any risks?
Many imaging procedures are painless or involve only mild, brief discomfort, though some more invasive tests may involve sedation or a small associated risk that will be explained beforehand. Serious complications are uncommon with modern techniques and experienced practitioners. You'll be given specific information about risks relevant to your particular procedure and health background before you consent.
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How long does it take to get results?
Results are typically reviewed by a specialist and reported within a few working days, though timeframes can vary depending on complexity. Some findings may be discussed with you immediately after the procedure, with a full written report to follow. The clinic will confirm the expected timeframe when you book.
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What happens if something abnormal is found?
If the results show something unexpected, a specialist will explain what it means and recommend appropriate next steps, which might include further imaging, a biopsy, or referral to a relevant specialist. Many abnormal findings turn out to be minor or unrelated to any symptoms once fully assessed. You'll be talked through the findings rather than left to interpret a report alone.
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Is this available on the NHS, or is private quicker?
This type of procedure is generally available on the NHS, but routine referrals can involve a wait for both the appointment and the results. Private providers typically offer appointments within days and results reviewed by a specialist soon after, which can be helpful if you want quicker reassurance or a second opinion. Cost for private testing varies by provider.
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How accurate is this type of test?
When performed by trained specialists on appropriate equipment, this is generally considered a reliable and clinically well-established investigation. As with any single test, results are best interpreted alongside your symptoms and other findings rather than in isolation. If a result is unclear or unexpected, further imaging or a repeat test may be recommended.
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How do I book ECG explained privately?
You can usually book directly with a private clinic, often without needing a GP referral, with appointments typically available within a matter of days. It's worth asking about preparation requirements and what the appointment will involve when you book. Contact the clinic for current availability and to discuss any specific concerns.