Ambulatory cardiac monitoring · Patient guide
Holter monitor, the classic 24-48 hour ambulatory ECG — palpitations, syncope and AF screening.
Palpitations that only ever happen off the treadmill, an unexplained blackout, or a pulse your GP thinks might be AF — the resting twelve‑lead has already come back normal, and this is the test that catches what it missed. Fitted at a central London cardiology clinic in fifteen minutes, worn for a day or two on your usual routine, then read by a consultant against your symptom diary.
Why patients choose us
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The right hands
We route you to a consultant cardiologist — a rhythm specialist reads your Holter trace, not a generalist.
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Report in 5–7 days
Your recorder is analysed and the cardiology report typically follows within a week of return.
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Independent, and free
We are paid by no clinic, so the recommendation is impartial and costs you nothing.
Key facts
What a Holter monitor is, in six lines.
A quick orientation before the detail — device, wear, diary, turnaround, and when to escalate.
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The fastest way to catch a rhythm a resting ECG missed
A matchbox‑sized recorder — or a discreet skin patch — capturing every heartbeat for 24 to 48 hours while you go about a normal London day and night.
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Patch or wired — same trace
A discreet adhesive patch or a small wired recorder in a pouch; the ECG your cardiologist reads is the same either way.
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Fitting
Skin electrodes attached at a short fitting appointment.
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Symptom diary
You keep a diary of symptoms and activities during wear.
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Turnaround
Cardiology report typically within 5–7 days.
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If events are rare
For less-frequent events, use a patch (7–14 days) or an implantable loop recorder.
Preparation and process
From consultation to report — what happens, in order.
Seven simple steps. The most important one you do — the diary.
Phase 1 · Before
Cardiology consultation
Phase 2 · On the day and wear
Fitting + 24–48 hours at home
Phase 3 · After
Return and report
- 01
Before
Cardiology consultation
A consultant cardiologist reviews your symptoms and confirms Holter is the right first-line test.
- 02
On the day / wear
Skin prepared
The chest is cleaned and lightly abraded so the electrodes stick well for the full wear.
- 03
On the day / wear
Electrodes and recorder attached
A 3-lead patch or wired recorder is fitted at the clinic — takes about 15 minutes.
- 04
On the day / wear
Wear device 24–48 hours
You go about your normal day. No showering with wired devices; patches are splash-resistant.
- 05
On the day / wear
Diary of symptoms and activities
Note palpitations, dizziness, chest pain and what you were doing — this is what unlocks symptom-rhythm correlation.
- 06
After
Return device
You drop the recorder back to the clinic (or post it, depending on device).
- 07
After
Cardiology report
A consultant cardiologist reports the full trace, with a plain-English summary and next step.
Typical end-to-end: 7–10 days from fitting to report.
What it shows
What a Holter can — and can’t — catch.
A Holter answers a specific question: what rhythm is your heart in over 24–48 hours, and does it match what you feel.
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Paroxysmal AF
Intermittent atrial fibrillation that a resting ECG will miss.
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SVT
Supraventricular tachycardia — narrow-complex fast rhythms.
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Ventricular ectopy burden
Quantifies PVC burden — a driver of symptoms and, if very high, cardiomyopathy.
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Non-sustained VT
Runs of ventricular tachycardia under 30 seconds — a prognostic finding.
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Sinus pauses
Long asystolic pauses, especially at night, that can explain syncope.
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Symptom–rhythm correlation
The whole point of the diary — matching what you felt to what the trace shows.
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Nocturnal bradycardia
Slow overnight rates — normal in athletes, a pacemaker question in others.
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Red flag: sustained VT or complete heart block with syncope — urgent cardiology admission
Do not wait for a routine report. Call your cardiologist or attend A&E.
Next steps and treatment
What follows the Holter — reassurance, or a defined pathway.
The report is only useful if it leads to a decision. These are the routes a cardiologist takes from a Holter finding.
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Reassurance if normal
A clean Holter with a full symptom diary is meaningful reassurance — often the answer.
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Extended monitoring (14-day patch, ILR)
If events are less frequent than the wear window, escalate to a 14-day patch or an implantable loop recorder.
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Rate / rhythm control
Beta-blockers, rate-control agents or antiarrhythmics — chosen with the cardiologist.
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Anticoagulation
If AF is confirmed, stroke-risk-based anticoagulation per NICE NG196.
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Pacemaker for symptomatic bradycardia
For symptomatic pauses, high-grade AV block or symptomatic sinus node disease.
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ICD for VT
Implantable cardioverter-defibrillator for sustained VT or high-risk substrate.
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Ablation referral
Catheter ablation for AF, SVT and selected VT — a same-network electrophysiology referral.
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Structured cardiology follow-up
A written plan and a scheduled review — not a one-off scan and silence.
Red flags
When a Holter finding is not routine.
The following either bypass the routine report pathway (urgent cardiology admission) or reshape the entire work-up.
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Sustained VT
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Complete heart block
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Long pause with syncope
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Long QT with syncope
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Wolff-Parkinson-White
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Brugada
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Family history of sudden cardiac death
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Congenital heart disease
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Cryptogenic stroke with AF found on monitoring
Any sudden collapse, chest pain, or one-sided neurological symptom is a 999 call — not a routine private appointment.
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 Holter monitors.
Quick answers on comfort, showering, turnaround, what a normal trace means, and when to escalate to patch or ILR.
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How soon can I get a private Holter monitor fitted in London?
Most central London cardiology clinics can fit a Holter within one to three working days, evenings and Saturdays included. Fitting takes about fifteen minutes; the recorder comes off after 24 or 48 hours and a consultant cardiologist reports the trace against your symptom diary inside a week.
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Is a Holter monitor uncomfortable?
No. It’s a small recorder with sticky electrodes on the chest. Most patients forget they’re wearing it after an hour. Patch devices are even more discreet.
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Can I shower with a Holter monitor?
With a wired Holter, no — most clinics ask you to wait until the recorder is returned. Patch monitors are usually splash-resistant, so a quick shower is fine. Your clinic will tell you which yours is.
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How long will I wait for results?
A cardiology report typically follows within 5–7 days of return, sometimes sooner. Urgent findings (sustained VT, complete heart block, long pauses with syncope) are flagged immediately.
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What if my symptoms don’t happen during the wear?
That’s why the diary matters — a symptom-free 48 hours is still information. If your symptoms are rarer than the wear window, we escalate to a 7–14 day patch or an implantable loop recorder.
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When is a Holter the right test versus other monitors?
Holter is first-line when symptoms are daily or near-daily. For less frequent events, patch monitors (7–14 days) or an implantable loop recorder (up to 3 years) give a better chance of catching the rhythm.
Sources
What this page is grounded in.
Reviewed by Pulse Atlas Editorial Board (). Last reviewed 2026-07-30. Next review 2027-07-30.
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In practice, in London
The London pathway for holter monitor
With holter monitor, 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 holter monitor 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.
A private holter monitor pathway in London usually looks like this: an initial consultation, any diagnostics booked at a nearby facility (most within Zone 1 or 2), and a written report sent to you and your GP within a few days. The consultants we work with hold NHS posts alongside their private lists, which keeps the standards consistent across both settings. For holter monitor specifically, the difference between a routine report and a sub-speciality read is where private care earns its keep.
Honesty about expectations is part of the job. A private holter monitor appointment in London won’t change the underlying medicine — the guidelines, the consultants, and the equipment are largely the same as on the NHS. What it changes is speed, continuity, and the amount of time you get to actually talk through the findings. Everyone we route to is GMC-registered and works within CQC-regulated facilities.
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