Syncope is very common and will affect 42% of people during their lifetime
Initial assessment of the syncope patient
In this section:
Things to ask the patient (and preferably a witness)
|Circumstances or triggers||
|Posture||Standing, sitting or lying flat|
|History of syncope||First event or number and frequency of previous episodes.|
|Past medical history|
|Family history||Premature sudden cardiac death at age of under 40 years, inherited heart disease.|
The 3 P’s of vasovagal syncope
The presence of the following features would suggest vasovagal syncope:
- Posture – prolonged standing, or similar episodes that have been prevented by lying down
- Provoking factors (such as pain or a medical procedure)
- Prodromal symptoms (such as sweating or feeling warm/hot before TLoC).
Examination of patient
- Cardiovascular examination
- Neurological examination if indicated by the history
- Other systems as appropriate
- Active stand test.
Within a 10-minute consultation, it may be impossible to conduct all aspects of the assessment and it may be necessary, after risk assessment, to arrange a follow-up consultation.
Red flags in syncope
Refer urgently, anyone with transient loss of consciousness (TLoC) who also has any of the following:
- ECG abnormality
- TLoC during exertion (syncope after stopping exercise is mostly vasovagal)
- Family history of sudden cardiac death in people aged younger than 40 years and/or an inherited cardiac condition
- Heart failure (history or physical signs)
- New or unexplained breathlessness
- Undiagnosed heart murmur
- Anyone aged older than 65 years who has experienced TLoC without prodromal symptoms
- Presence of severe structural heart disease or coronary artery disease
- Syncope when supine
- Sudden onset palpitation immediately followed by syncope
- When preceded by chest pain, abdominal pain or headache
- Short prodrome
- Unexplained systolic BP below 90 mmHg
- Suggestion of gastrointestinal bleed
- Bradycardia 40 (awake and in absence of physical fitness).
Referenced from NICE Blackouts guidance 2010 and the 2018 ESC Guidelines for the diagnosis and management of syncope.
Risk stratification tools
Risk stratification tools are of limited value and have not been shown to perform better than good clinical judgement in identifying patients at high risk of serious short-term outcomes. Most risk assessment tools were developed for use in the emergency department and no risk assessment tools have been validated in primary care.
Syncope educational resources for healthcare professionals
- Transient loss of consciousness ('blackouts') in over 16s - clinical guideline [CG109], last updated: 01 September 2014
- European Society of Cardiology - Guidelines on diagnosis and management of Syncope, 2018
- 2015 Heart Rhythm Society expert consensus statement on the diagnosis and treatment of Postural tachycardia syndrome, Inappropriate sinus tachycardia, and Vasovagal syncope
- Syncopedia is a website containing free, high quality syncope education. It is targeted at students, residents, nurse specialists and physicians that want to learn more about syncope.