Patient guide · Cardiology
ECG recorders, from resting 12-lead to KardiaMobile — how to capture the right heart rhythm.
An ECG (electrocardiogram) recorder captures the electrical activity of the heart. Options range from the 5-minute resting 12-lead in clinic to smartphone-based single-lead devices (KardiaMobile, Apple Watch) and multi-day patches — chosen by symptom frequency and clinical question.
Why patients choose us
- 01
The right recorder for the question
We match device to symptom frequency — a resting 12-lead won’t catch a once-a-month palpitation, and a 14-day patch is wasted on daily episodes.
- 02
Read by a cardiologist
Every trace — resting, smartphone or patch — is interpreted by a consultant cardiologist, not an algorithm alone.
- 03
Independent, and free
We are paid by no clinic, so the recommendation is impartial and costs you nothing.
Key facts
What an ECG recorder is, in six lines.
The essentials — what the device does, which types exist, and who reads the trace.
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What it is
An ECG (electrocardiogram) recorder is a device that captures the electrical activity of the heart.
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The office standard
12-lead resting ECG remains the standard first-line recording in clinic.
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Smartphone and smartwatch ECG
Single-lead devices (KardiaMobile, Apple Watch) capture rare, self-triggered events at home.
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Multi-day patches
Modern adhesive patch monitors (Zio and similar) record continuously for 7–14 days.
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Implantable loop recorder
For very infrequent events, a small subcutaneous device can monitor for up to three years.
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Cardiologist interpretation
Whichever device is used, the trace must be interpreted by a cardiologist to be clinically actionable.
How it’s done
From consultation to report — what happens, in order.
Seven practical steps, from picking the right device to getting a written cardiologist report.
Phase 1 · Before
Consultation and device choice
Phase 2 · Recording
Seconds to weeks of capture
Phase 3 · After
Data and cardiologist report
- 01
Before
Cardiology consultation
A consultant cardiologist takes the history — symptom pattern, frequency, triggers, family history — and frames the clinical question.
- 02
Before
Choose device by symptom frequency
Daily → 24-hour Holter. Weekly → 7-day patch. Rare → smartphone / smartwatch. Very rare with syncope → implantable loop recorder.
- 03
Recording
Skin prepared with alcohol
Chest sites are wiped with alcohol (and lightly shaved if needed) so electrodes adhere and signal quality is clean.
- 04
Recording
Electrodes applied
Ten leads for a 12-lead resting ECG, or a small patch / single-lead device depending on the plan.
- 05
Recording
Recording captured
Seconds for a resting ECG, 24 hours to 14 days for ambulatory monitors, up to three years for an implantable loop recorder.
- 06
After
Data uploaded or downloaded
Smartphone traces upload from the app; patches are returned by post; loop recorders transmit remotely.
- 07
After
Cardiologist report
A consultant cardiologist reviews the raw trace and issues a written report with a concrete next step.
Reading time: 5 minutes. Reviewed: 2026-07-30.
What it shows
The rhythms and patterns a recorder can catch.
From normal sinus rhythm through common arrhythmias to inherited channelopathy patterns — plus the red flag that skips outpatient triage entirely.
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Sinus rhythm variants
Normal rhythm and physiological variants — the reassuring baseline.
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Atrial fibrillation / flutter
Irregular atrial rhythms — the commonest treatable driver of stroke risk.
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Supraventricular tachycardia
Sudden fast, regular rhythms arising above the ventricles.
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Ventricular ectopy
Extra beats from the ventricles — often benign, sometimes not.
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Non-sustained VT
Short runs of ventricular tachycardia — a marker that warrants further work-up.
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Bundle branch block
Conduction delay through the ventricles, visible on the QRS morphology.
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Long QT / Brugada pattern
Inherited channelopathy patterns that raise sudden-death risk.
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Red flag: sustained VT or complete heart block with syncope — urgent cardiology admission
Do not wait for an outpatient slot. This is an emergency assessment.
Next steps
What follows an ECG recording.
From reassurance through medication, ablation and device therapy — each pathway a cardiologist may recommend once the trace is read.
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Reassurance if normal
A normal trace, in the right clinical context, is often the whole answer.
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Medication for arrhythmia
Rate-control or rhythm-control drugs depending on the arrhythmia and symptom burden.
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Anticoagulation for AF
Direct oral anticoagulants to reduce stroke risk once atrial fibrillation is confirmed.
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Ablation referral
Catheter ablation for suitable SVT, AF and some ventricular arrhythmias.
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Pacemaker for bradycardia
Permanent pacing where the recording shows symptomatic bradycardia or heart block.
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Implantable defibrillator (ICD)
For patients at high risk of sudden cardiac death, based on the trace and imaging.
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Structured cardiology follow-up
A defined review interval — not left to drift — with a clear escalation trigger.
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Continue self-monitoring at home
Smartphone or smartwatch capture of any recurrence, brought to the next appointment.
Our vetted London network
A small panel of cardiology clinics, we picked them.
Partners across central, north, west and south London. Not listed publicly — introductions are made privately, once we understand your case.
Selection criteria
How we choose every clinic in our network.
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Consultant cardiologists with electrophysiology or general-cardiology expertise
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Full device range — 12-lead, 24-hour Holter, 7–14-day patch, smartphone ECG and loop recorder
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Manual over-read of every ambulatory trace — not algorithm-only reporting
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Onward electrophysiology or device pathway if the recording demands it
Red flags
When a trace can’t wait for an outpatient slot.
Findings and clinical contexts that need urgent cardiology or electrophysiology input rather than routine review.
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Sustained VT
Prolonged runs of ventricular tachycardia — treat as an emergency, not an outpatient issue.
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Complete heart block
Third-degree AV block — urgent cardiology admission for pacing decisions.
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Long pause with syncope
A significant asystolic pause with loss of consciousness needs same-day cardiology assessment.
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Long QT with syncope
Prolonged QT interval together with fainting is a sudden-death warning — urgent electrophysiology review.
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Brugada pattern
Characteristic ST-elevation pattern requires specialist electrophysiology assessment and family screening.
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Wolff-Parkinson-White
Pre-excitation pattern — risk-stratify with electrophysiology, especially in the young.
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Persistent tachycardia with heart failure
Ongoing fast rhythms driving cardiac dysfunction — do not delay specialist input.
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Family history of sudden cardiac death
Any suspicious trace in this context deserves a low threshold for further investigation.
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Congenital heart disease
Underlying structural disease changes how any arrhythmia is interpreted and managed.
Reading your report
An ECG report can look intimidating. It isn’t.
Whichever recorder produced the trace, the report keeps to the same four parts.
A quiet reminder
The report is written for your doctor, not for you — and that’s normal.
If you would like us to talk you through it before your follow-up, just ask.
- 01 Header
Indication and device used
Your details, the clinical question, and which recorder captured the trace — resting 12-lead, Holter, patch, smartphone or loop recorder.
- 02 Technique
Recording duration and quality
How long the recording ran, artefact burden, and whether patient-triggered events were logged.
- 03 Findings
Rhythm, rate, intervals, ectopy
Dominant rhythm, rate ranges, PR/QRS/QT intervals, ectopy burden and any captured arrhythmias.
- 04 Impression
The conclusion: read this first
Normal, benign variant, or actionable arrhythmia — and the concrete next step. Read this first.
Recognised by major UK insurers
Cover depends on your policy and clinic; we confirm with your insurer before booking.
Frequently asked
Everything we get asked about ECG recorders.
Quick answers on device choice, smartwatch ECGs, patch duration, loop recorders and who interprets the trace.
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What is an ECG recorder?
An ECG (electrocardiogram) recorder is a device that captures the electrical activity of the heart. It ranges from the 5-minute resting 12-lead ECG in clinic through smartphone-based single-lead devices (KardiaMobile, Apple Watch) to multi-day patches and implantable loop recorders.
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Which ECG recorder is right for my symptoms?
Device choice is driven by how often the symptom happens. Daily palpitations suit a 24-hour Holter, weekly episodes a 7–14-day patch (like Zio), rare events a smartphone / smartwatch ECG, and very rare episodes with syncope an implantable loop recorder.
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Is a smartwatch ECG good enough?
Single-lead smartphone and smartwatch ECGs (KardiaMobile, Apple Watch) are excellent for capturing rare events the patient can feel and self-record. They are not a substitute for a 12-lead ECG or a multi-day monitor when a full rhythm work-up is needed.
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How long does a patch monitor record for?
Modern adhesive patches such as Zio typically record continuously for 7 to 14 days, with the patient wearing it under normal clothing and pressing a button to log any symptoms.
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When is an implantable loop recorder used?
For infrequent events — particularly unexplained syncope — where surface recorders miss the episode. It sits under the skin and monitors continuously for up to three years, transmitting remotely.
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Who interprets the recording?
Every trace, whichever device produced it, is interpreted by a consultant cardiologist. Algorithms help flag events, but the clinical decision rests with the cardiologist.
Sources
Guidance we rely on.
- NICE. Atrial fibrillation: diagnosis and management (NG196).
- European Society of Cardiology. Clinical practice guidelines.
- Heart Rhythm Society. Clinical resources and guidelines.
- British Heart Foundation. Heart rhythm information.
Last reviewed 2026-07-30. Next scheduled review 2027-07-30.
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In practice, in London
How ECG recorder tends to unfold when you go private
With ECG recorder, the London question is usually about report turnaround and the radiologist reading it — not whether the scan is available. Waiting lists on the NHS for ECG recorder vary widely by borough and by how the GP letter reads. Privately in London, we can normally offer a slot inside the same week, sometimes within 48 hours if there’s a cancellation. The difference isn’t clinical quality — the consultants are frequently the same faces you’d see on the NHS — it’s the calendar.
Once you’re in the private system for ECG recorder, the pace picks up noticeably. Consultant slots run to time, imaging is usually available in the same building or a short walk away, and the report comes back typed and detailed. It’s the coordination that tends to feel different — one person on the other end of the phone, not a switchboard. For ECG recorder specifically, the difference between a routine report and a sub-speciality read is where private care earns its keep.
The value of going through a concierge for ECG recorder isn’t access — anyone with an insurer or a credit card can get a private appointment in London. The value is knowing which consultant reads this particular presentation best, which unit turns reports around fastest, and which pathway won’t hit a dead end if the findings point somewhere unexpected.
Nearby in the library