Cardiac Monitoring
Ambulatory ECG — Holter Monitoring
A continuous heart rhythm recording worn during daily life. When symptoms are intermittent, ambulatory monitoring is the key to capturing what a standard resting ECG will almost certainly miss.
The Test
Capturing the Heart Rhythm When It Matters Most
Palpitations, dizziness, blackouts, and breathlessness are frequently intermittent — they come and go unpredictably, and are often absent at the precise moment a standard resting ECG is recorded. Ambulatory ECG monitoring solves this problem by recording the heart's electrical activity continuously while you go about your normal life.
The technology has advanced dramatically. Where a 24-hour Holter monitor was once the only option, there are now devices that can monitor for up to two weeks on the skin, or be implanted under the skin for up to three years — ensuring that even the most infrequent of arrhythmias can eventually be captured and correlated with symptoms.
Dr Nijjer personally analyses all recordings, paying particular attention to the timestamps you record in a symptom diary, so that your ECG trace can be examined at the precise moment you experienced symptoms. This symptom-rhythm correlation is the most clinically valuable part of the entire investigation.
Available Monitoring Options
Six Ways to Record Your Heart Rhythm
Dr Nijjer will select the most appropriate monitoring method based on the frequency of your symptoms, your lifestyle, and the clinical question being asked. The duration of monitoring should be matched to how often symptoms occur.
The classic ambulatory recorder: electrodes on the chest connect to a portable device worn on a belt or lanyard. Records three simultaneous ECG leads continuously. You keep a diary of symptoms noting the time they occur. Ideal for daily or near-daily symptoms.
Similar hardware to a Holter monitor but you press a button to capture the ECG only when you experience symptoms. This saves storage and focuses analysis on symptomatic events. Some models also have an auto-trigger that detects abnormal rhythms independently.
A slim, waterproof adhesive patch worn directly on the chest for up to 14 days — you can shower and swim normally. Studies demonstrate a superior diagnostic yield compared to traditional Holter monitors for capturing infrequent palpitations, detecting approximately 2–4 times more arrhythmias.
A small device (roughly the size of a USB stick) is implanted just beneath the skin in a minor procedure under local anaesthetic. It monitors the heart rhythm continuously for up to three years, auto-detecting arrhythmias and allowing you to manually record episodes. Essential for infrequent blackouts or suspected cryptogenic stroke.
A small medical-grade sensor that pairs with a smartphone app. You record a single-lead ECG by placing fingers on the electrodes for 30 seconds, generating a PDF-quality recording that can be sent directly to Dr Nijjer for review. FDA-cleared to detect atrial fibrillation, bradycardia, and tachycardia.
Apple Watch Series 4 and later can record a single-lead ECG via the back sensor and finger contact. The algorithm is validated for atrial fibrillation detection. While clinically useful for capturing symptomatic episodes, it is important to discuss any alerts with Dr Nijjer before acting on them, as false positives can cause unnecessary anxiety.
What to Expect
Wearing Your Monitor
A cardiac physiologist will attach the electrodes and connect the monitoring device at the clinic. For a standard Holter or ZioPatch this takes around 10 minutes. The device is worn under your clothing and should not restrict your daily activities.
- Keep a symptom diary: Note the exact time of any palpitations, dizziness, chest discomfort, or breathlessness — this is the most valuable information Dr Nijjer will use to correlate your ECG with your symptoms.
- Carry on as normal: Exercise, work, and social activities should continue as usual — the recording is most valuable when it captures your typical daily rhythm.
- Avoid strong electromagnetic fields: Keep the device away from strong magnets, MRI scanners, and electric induction hobs.
- Waterproof devices: The ZioPatch is water-resistant; traditional Holters should be removed before showering or bathing unless you have a waterproof cover.
- Return at the scheduled time: The device is returned to the clinic, the data downloaded, and Dr Nijjer performs a full analysis.
Understanding Your Findings
Interpreting the Recording
What Dr Nijjer Looks For in Your Trace
The recording is analysed for the total number and type of ectopic beats, the presence and burden of atrial fibrillation, any episodes of supraventricular or ventricular tachycardia, pauses in the heart rhythm, and the minimum, maximum, and average heart rate over the monitoring period.
The key question is whether any rhythm abnormality coincides with the timestamps in your symptom diary. A symptom with a perfectly normal rhythm at the time rules out an arrhythmic cause and points investigation elsewhere. A rhythm abnormality at the precise moment of symptoms confirms a diagnosis and guides treatment directly.
Results are discussed at a follow-up appointment, with the relevant parts of the trace shown to you on screen so you can understand exactly what was found. If the recording was entirely normal during symptoms, further investigation with a different monitoring modality — or an alternative diagnosis — will be considered.
Experiencing Unexplained
Palpitations or Dizziness?
Ambulatory ECG monitoring is the key to capturing intermittent rhythm disturbances. Dr Nijjer will select the most appropriate device and analyse the recording personally.