1) The patient experienced a transient loss of consciousness while exercising on a bike. She had no warning symptoms, tongue biting, or confusion after. Witnesses reported spasming but no seizure activity. 2) Initial assessment found no abnormalities on exam, ECG, or bloodwork. Prehospital and hospital ECGs were normal. 3) The syncope is believed to be non-cardiac and vasovagal in nature, likely precipitated by dehydration and eating disorder contributing factors. The patient was discharged with reassurance and advice.

1. TLoC / Syncope
Simon Mark Daley

2. Key documents;
• Transient loss of consciousness (‘blackouts’) in over 16s – 2010
NICE cg109 (more relevant).
• Guidelines for the diagnosis and management of syncope –
2009 ESC guideline (interesting).

3. Introduction;
• TLoC is common; it affects 50% of the UK population at some
point in their lives.
• TLoC may defined as a spontaneous loss of consciousness with
complete recovery (recovery of consciousness without any
residual neurological deficit).
• There are a variety of causes of TLoC including cardiovascular
causes (most common), neurological, and psychogenic.

4. • Diagnosis of the underlying cause is often inaccurate,
inefficient and unnecessarily delayed.
• Management varies significantly.
• A large proportion of patients diagnosed with and treated for
epilepsy, have a cardiovascular cause
• This wastes time and money, and is potentially dangerous for
the patient.
• To reduce these issues, standardisation of initial assessment,
diagnosis and specialist referral are imperative.

5. Urgent cardio assessment;
(these are the people we should be asked to RV)
any of the following;
• ECG abnormality (I’ll define this in a moment).
• Acute and/or known HF.
• Exertional TLoC.
• FH of SCD aged <40 and/or an inherited cardiac condition.
• New or unexplained breathlessness.
• Heart murmur.
• Anyone aged >65 without prodrome.

6. Initial assessment;
• Specific circumstances.
• Posture immediately prior to TLoC.
• Prodromal symptoms.
• Appearance and colour/pallor.
• Movement during eg limb-jerking.
• Tongue biting.
• Injury sustained.
• Duration (onset to regaining consciousness).
• Confusion post event.
• Weakness during recovery period.

7. 12 lead ECG;
• abnormalities;
• Conduction abnormalities such as BBB or 1/2/3AVB.
• Long or short QT interval (>450ms or <350ms respectively).
• ST-segment deviation.
• T-wave abnormalities.
• Other potentially significant abnormalities;
• Inappropriate or persistent bradycardia.
• Any ventricular arrhythmia (including VEs).
• Brugada syndrome.
• Ventricular pre-excitation.
• LVH or RVH.
• Pathological Q waves.
• Sustained atrial arrhythmia.
• Paced rhythm.
Crucial to review pre-hospital monitoring, not just ED/IP monitoring

8. Specialist cardiac assessment;
• Detailed history of TLoC including previous events.
• Medical history and FH.
• Drug therapy at the time of the TLoC and any
subsequent/recent changes.
• Full cardiovascular examination and - if appropriate -
consideration of lying and standing BPs.
• Scrutiny of current and previous ECGs.
• Assign the person one of the following suspected causes of
syncope;
• Suspected structural heart disease.
• Suspected cardiac arrhythmia.
• Suspected neurally mediated.
• Unexplained.

9. Where cardiac arrhythmia
suspected (exercise);
• History should distinguish between those with exercise-
induced syncope occurring during exercise (when arrhythmia
is probable) and those whose syncope occurred shortly after
stopping exercise (where a vasovagal cause is more likely).
• For syncope during exercise offer urgent exercise testing unles
there is contraindication (such as suspected AS or HCM).
Advise the patient to refrain from exercise in the meantime.

10. Where cardiac arrhythmia
suspected (non-exercise);
• Offer ambulatory ECG, and do not offer tilt test as first line.
Type of ambulatory ECG determined by history and frequency;
• Where TLoC occurring several times per week, offer Holter
monitoring (up to 48hrs). If no symptoms during this period,
offer external event recorder that provides continuous
monitoring with facility for patient to activate when
symptomatic.
• Where TLoC every 1-2 weeks, offer external event recorder. If
no symptoms during this period, offer implantable event
recorder.
• Where TLoC infrequently, offer implantable event recorder.

11. Non-cardiac causes;
• Diagnose an uncomplicated faint on initial assessment when;
• There are no features suggestive of an alternative diagnosis
• The 3 Ps;
• Posture - prolonged standing
• Provoking factors – pain or a medical procedure
• Prodrome – such as sweating or flushing sensation
Note that brief seizure activity can occur during uncomplicated
faints and is not necessarily diagnostic of epilepsy

12. Non-cardiac causes;
• Diagnose situational syncope based on initial assessment
when;
• There are no features suggestive of an alternative diagnosis
and
• Syncope is clearly and consistently provoked by straining during
micturition or by coughing/swallowing

13. Non-cardiac causes;
• Suspect orthostatic hypotension based on initial assessment
when;
• There are no features suggestive of an alternative diagnosis
and
• The history is typical
• If these criteria are met, measure lying and standing BP (ensure
standing for 3 mins) and if confirmed, consider likely causes such
as drug therapy

14. Non-cardiac causes;
• Refer to a specialist in epilepsy when >1 of the following;
• A bitten tongue
• Head turning to one side during TLoC
• No memory of abnormal behaviour pre/post or during TLoC from
witness
• Unusual posturing
• Prolonged limb-jerking (note some seizure-like activity can occur
in uncomplicated faints)
• Confusion post-TLoC
• Prodromal deja-vu or jamais-vu
EEG should not routinely be used to investigate TLoC

15. Unexplained syncope;
• If aged >60 offer carotid sinus massage as a first line
investigation (in an appropriate clinical environment).
56% of unexplained syncope are found to have carotid sinus
hypersensitivity
• All patients with unexplained syncope should have ambulatory
ECG (24hr tape) (assuming CSM negative).

16. If the cause remains uncertain...
• Consider psychogenic non-epileptic seizures (PNES) or
psychogenic pseudosyncope if;
• The nature of events changes over time.
• There are multiple unexplained physical symptoms.
• There are unusually prolonged events.
Neurological assessment is required in these types of cases.
• Advise the patient to try to record future events (Eg; a video
recording or detailed witness account).
• Consider the possibility that more than one mechanism may co-
exist.

17. Patient advice;
• Advise patients that they must not drive whilst they await a
specialist opinion.

18. Case Study;
• 36yo female w/ history of depression, anxiety, eating disorder
• HoPC;
• Syncope whilst using exercise bike.
• 25 mins into light gym workout.
• Woke up on the floor.
• No incontinence.
• No prodrome/warning symptoms.
• Body appeared to spasm according to witnesses (no seizure).
• No tongue biting.
• # clavicle falling from bike.
• 2-3min duration.
• No confusion, although wasn’t immediately aware of events.
• No weakness.

19. Case Study;
• No previous syncope or exertional symptoms when
swimming/walking
• Has previously experienced dizziness upon standing and simple
feints when giving blood, extremely anxious/stressed.
• No family history of syncope, sudden cardiac/unexplained death,
arrhythmia, heart disease.
• Admitted she had only eaten half a banana and had not sufficiently
hydrated herself prior to/during workout.
• DHx; Fluoxetine, Propanolol, PRN Diazepam (all started 2/12 ago).
• Exam unremarkable, including normal heart sounds and pulses,
other than that patient appeared cachexic.
• Negative lying and standing BP.
• Haemodynamics stable throughout (EMAS to AE).

20. Case Study;
• Bloods; Grossly normal.
• ECG;
• NSR 74bpm.
• Normal cardiac axis.
• Normal QTc (calculated manually as given as 476ms on one ECG).
• None of the following;
• AVB / BBB / conduction abnormalities.
• ST segment deviation or T wave abnormalities.
• Arrhythmia including ectopy.
• Bradycardia.
• Pre-excitation or Brugada pattern.
• Q waves.
• LVH or RVH

21. Case Study; Prehospital ECG

22. Case Study; A&E ECG

23. Case Study;
• Impression;
• Unlikely cardiac syncope – no high risk ECG features and more
likely explanation.
• Likely vasovagal syncope precipitated by dehydration and
contributed to by eating disorder.
• Plan;
• Discharged w/ reassurance and verbal advice