Quality statement 6: Specialist cardiovascular investigation – ambulatory electrocardiogram (ECG)

Quality statement

People with a suspected cardiac arrhythmic cause of syncope are offered an ambulatory electrocardiogram (ECG) as a first‑line specialist cardiovascular investigation.

Rationale

In some people, transient loss of consciousness is caused by a transient episode of abnormal heart rhythm (cardiac arrhythmia) that has resolved before recovery or initial assessment. Ambulatory ECGs allow prolonged monitoring to try to detect intermittent episodes of cardiac arrhythmia (and also of abnormal heart rate behaviour). The monitoring takes place over at least 24 hours, and often much longer.

Recording heart rate and rhythm behaviour at the time of an episode of transient loss of consciousness allows confident diagnosis. Competent expert interpretation is also needed to assess the relevance of abnormal heart rate and rhythm behaviour recorded at a time when the person has no symptoms.

Quality measures

Structure

Evidence of local arrangements to ensure that people with a suspected cardiac arrhythmic cause of syncope are offered an ambulatory ECG as a first‑line specialist investigation, with the type of ambulatory ECG chosen according to the person's history and frequency of transient loss of consciousness.

Data source: Local data collection.

Process

Proportion of people with a suspected cardiac arrhythmic cause of syncope who are offered an ambulatory ECG as a first‑line specialist investigation.

Numerator – the number in the denominator who receive an ambulatory ECG as a first‑line specialist investigation, with the type of ambulatory ECG chosen according to the person's history and frequency of transient loss of consciousness.

Denominator – the number of people with a suspected cardiac arrhythmic cause of syncope.

Data source: Local data collection.

What the quality statement means for service providers, healthcare professionals and commissioners

Service providers (acute, primary and secondary care) ensure that systems are in place to offer ambulatory ECGs as a first‑line specialist cardiovascular investigation for people with a suspected cardiac arrhythmic cause of syncope.

Healthcare professionals ensure that they offer an ambulatory ECG as a first‑line specialist cardiovascular investigation for people with a suspected cardiac arrhythmic cause of syncope.

Commissioners (NHS England area teams and clinical commissioning groups) ensure that they enhance training and education on offering an ambulatory ECG as a first‑line specialist cardiovascular investigation for people with a suspected cardiac arrhythmic cause of syncope. They should also request evidence of practice from providers that ambulatory ECGs are being offered as a first‑line specialist cardiovascular investigation.

What the quality statement means for patients, service users and carers

People whose blackout is suspected to be caused by a sudden change in heart rate or rhythm are offered an ambulatory ECG. This is a test that uses a small portable device to monitor and record the heart's activity over a period of time (usually more than 24 hours).

Source guidance

Definitions of terms used in this quality statement

Ambulatory ECG

A test that monitors and/or records the electrical activity of the heart over a prolonged period of at least 24 hours, while the person is walking about (ambulatory) and doing other normal activities, including resting or sleeping.

Ambulatory ECG monitors and/or recorders

Holter monitor/recorder

A small, portable recorder that can take continuous ECG readings from electrodes on the skin, usually over a 24‑ to 72‑hour period.

[Based on NICE clinical guideline 109 and expert opinion]

External event recorder

A small, portable recorder that can take ECG readings from electrodes on the skin; usually worn for 1–4 weeks. It will usually be programmed to detect and store episodes of extreme heart rate behaviour and can be triggered remotely (by the person or someone close to them) to store the current or immediately recent ECG at the time of an event, such as a further episode of transient loss of consciousness.

[Based on NICE clinical guideline 109 and expert opinion]

Implantable event recorder (also known as an implantable or insertable loop recorder, or implantable cardiac monitor)

A small, implantable device that can monitor and store ECG recordings of the heart's rhythm. It can be programmed to detect and store episodes of extreme heart rate behaviour and can be triggered remotely (by the person or someone close to them) to store the current or immediately recent ECG at the time of an event such as a further episode of transient loss of consciousness.

[Based on NICE clinical guideline 109 and expert opinion]

Cardiac arrhythmia

An abnormality of the heart's rhythm.

[Based on expert opinion]

Syncope

Transient loss of consciousness caused by transient reduction in blood flow to the brain. May be caused by many different factors, including vagal stimulation, vascular pooling in the legs, sudden change in environmental temperature or body position drug therapy, structural heart disease, cardiac arrhythmia, vertebro‑basilar atheroma and emotional stress.

[NICE clinical guideline 137 and expert opinion]