Holter ECG in Paris: a 24h monitor for your heart rhythm

It can reveal atrial fibrillation that comes and goes, extra beats, episodes of a fast or slow rhythm, and pauses, helping the cardiologist link these to symptoms such as palpitations, dizziness or fainting. It's also used to check that a rhythm treatment is working. Because it records continuously, it catches events a standard ECG, lasting only seconds, cannot. The cardiologist reviews the whole recording against your symptom diary, which is why noting the time of any palpitation or dizzy spell makes it so useful.

It works by continuously recording your heart's electrical signal through electrodes on the chest, wired to a small recorder you carry. The medical assistant fits it in about ten minutes, painlessly, and you then go home and live normally. During the recording, from 24 hours to two weeks, you keep a short diary noting the time of any symptoms, which helps match a sensation to the tracing. At the end, you return the recorder and the cardiologist analyses the full recording before explaining the results. Fitting and wearing one is simple and doesn't interrupt your daily routine.

From 24 hours up to two weeks, depending on what the cardiologist has prescribed. The more often your symptoms occur, the shorter the recording usually needs to be; when palpitations are rare, a longer recording improves the chance of catching an event. The cardiologist chooses the duration based on your symptoms and the question to answer. Throughout that time you wear it continuously, including at night, noting any symptom in the diary: the length is always matched to giving the clearest possible answer.

No. It's not waterproof, so avoid showering or bathing while wearing it, and don't stop or remove it during the recording period. The medical team explains this at fitting, and most patients simply plan a wash around it for the day or days they wear it. Keeping the electrodes clean, dry and in place ensures a clean signal from start to finish. If an electrode comes loose, follow the instructions given at fitting rather than stopping the device.

Yes. The recording is meant to capture your heart during everyday activity, so go to work, walk, follow your usual routine. Light activity is fine and even helpful, since it shows the cardiologist how your heart behaves under normal effort. Avoid only what would soak the device or dislodge the electrodes, such as swimming or heavy sweating, unless your cardiologist advises otherwise. Noting what you were doing when a symptom occurred makes the recording even more useful.

No. It uses adhesive electrodes on the skin, the same idea as a standard ECG, connected to a small recorder; nothing injected, no current sent into you. It's fitted in about ten minutes and is light and discreet under clothing. The only things to remember: keep the skin clean and dry, don't shower with it, and don't stop it during the recording.

A standard ECG records your heart's electrical activity for a few seconds; a Holter ECG records it continuously over 24 hours to two weeks. Both are painless and use electrodes on the skin, but they answer different questions. The cardiologist starts with an ECG because it's quick; if it's normal but an intermittent problem is suspected, such as palpitations that come and go, a Holter catches the arrhythmia during everyday life. A Holter is usually prescribed precisely because a single ECG can't capture a problem that isn't happening during those few seconds.

Both are worn over 24 hours or more, but they measure different things. The Holter ECG records the heart's electrical activity to detect rhythm disorders such as atrial fibrillation, while the Holter blood pressure monitor (MAPA) records your blood pressure at regular intervals to diagnose or follow hypertension. The cardiologist chooses the ECG version when the question is about rhythm, and MAPA when it's about blood pressure: see our MAPA page for that test in detail. The two can even be relevant to the same patient at different times.

Yes, that's one of the main reasons for this test. Atrial fibrillation is often intermittent and can be completely silent, so it frequently escapes a brief ECG. By recording continuously over 24 hours to two weeks, a Holter increases the chance of capturing an episode and confirming the diagnosis. Once found, the cardiologist, and a heart rhythm specialist when needed, assesses the associated risk, including stroke risk, and defines treatment. If your palpitations are rare, the cardiologist may choose a longer recording to improve the odds of catching the arrhythmia.

Come with clean, dry skin, no cream, so the electrodes adhere well, and plan not to shower while wearing it. You're given a short diary with the device to note the time of any symptom, such as a palpitation or dizzy spell, and what you were doing: this lets the cardiologist match what you felt to the exact tracing. Never stop the device during the recording. That's all the preparation this test requires.

A prescription from your doctor is generally required to carry out complementary examinations. If in doubt, our secretariat is available to advise you.

Use the online booking button on this page, or call the secretariat. Mention your symptoms, such as palpitations or dizzy spells, so we plan the right recording duration. Come with clean, dry skin on the day of fitting, and bring any prescription and previous recordings. New patients are welcome. If your symptoms are severe or sudden, such as fainting or lasting chest pain, treat it as an emergency and call 15 (SAMU) or 112 rather than waiting for an appointment.