Syncope

Question 1

Define what Transient Loss of Consciousness (TLOC) is

Answer 1

A state of real or apparent loss of consciousness with loss of awareness, characterized by amnesia for the period of unconsciousness, loss of motor control, loss of responsiveness, and a short duration

Question 2

List the causes of TLOC

Answer 2

• Head Trauma (traumatic TLOC)
• Syncope
• Epileptic Seizures
• TLOC mimics (e.g. psychogenic pseudo-syncope, psychogenic pseudo- seizures)
• Other causes

Question 3

Define what syncope is

Answer 3

Transient loss of consciousness due to cerebral hypoperfusion, characterized by rapid onset, short duration, and spontaneous complete recovery

Question 4

What are the 3 categories of syncope ?

Answer 4

1. Reflex Syncope
2. Orthostatic Hypotension
3. Cardiac Syncope

Question 5

Define what reflex syncope is

Answer 5

This is the preferred terminology for ALL types of syncope in which neural reflexes modify heart rate (cardioinhibition) and/or vascular tone (vasodepression) hence predisposing to a fall in Mean Arterial Blood Pressure (systemic hypotension) of sufficient severity to affect cerebral perfusion causing a transient period of cerebral hypoperfusion resulting in syncope or near syncope

Question 6

What are the 3 types of reflex syncope ?

Answer 6

1. Vasovagal Syncope (VVS)
2. Situational Syncope
3. Carotid Sinus Syncope (CSS)

Question 7

What is vasovagal sycnope ?

Answer 7

It is the commenest type of syncope. The faint is triggered by emotional distress (e.g. pain, fear, blood phobia) Or orthostatic stress (i.e. standing too long)

Question 8

What are the classical features of vasovagal syncope?

Answer 8

• Onset of faint is over seconds (not instantaneous) & is pre-ceeded by prodrome (nausea, pallor, sweating & closing in of visual fields)
• Brief clonic jerking may occur (reflex anoxic convulsion) but there is no stiffening ot tonic/clonic sequence
• Urinary incontinence is uncommon
• No tongue bitting
• Recovery is rapid

Question 9

Can a vasovagal syncope be averted ?

Answer 9

• Yes e.g. by adopting: horizontal gravity neutralisation position or leg crossing.
• These manoeuvres increase venous return

Question 10

What is the main risk to the patient who has episodes of vasovagal syncope ?

Answer 10

Injury when falling

Question 11

Is vasovagal syncope associated with increased mortality ?

Answer 11

No

Question 12

What is the treatment of vasovagal syncope ?

Answer 12

Education, reassurance, avoidance of triggers (if possible) and adequate hydration

Question 13

What is situational reflex syncope ?

Answer 13

It is a faint during or immediately after a specific trigger e.g. cough, micturition, swallowing, etc

Question 14

What are the classical features of situational reflex syncope ?

Answer 14

The same as vasovagal syncope

Question 15

What is the treatment of situational reflex syncope ?

Answer 15

• Treat the cause, if possible (e.g. cough)
• Advise patient to lie down, if possible (e.g. during a coughing episode)
• Avoid dehydration and excessive alcohol
• Cardiac permanent pacing may be needed in some cases od situational syncope

Question 16

What is Carotid Sinus Reflex Syncope?

Answer 16

This is where hypersensitive baroreceptors cause excessive bradycardia +/- vasodilatation on minimal stimulation particularly triggered by mechanical manipulation of the neck, shaving, tight collar, etc.

Question 17

Who is carotid sinus reflex syncope most common in ?

Answer 17

In elderly especially males

Question 18

What may carotid sinus reflex syncope be associated with ?

Answer 18

Occuring after head and neck surgery or radiation

Question 19

What is the treatment of carotid sinus reflex syncope ?

Answer 19

Cardiac permanent pacing

Question 20

Note orthostatic hypotension covered in another flashcard deck

Question 21

What is cardiac syncope

Answer 21

This is syncope caused by a cardiac event resulting in sudden drop in cardiac output:

• Arrhythmias: resulting in bradycardia or tachycardia
• Acute Myocardial infraction
• Structural Cardiac Disease: e.g. aortic stenosis, hypertrophic cardiomyopathy
• Other Cardiovascular Disease: e.g. pulmonary embolism, aortic dissection

Question 22

What are the features suggestive of a cardiac syncope ?

Answer 22

• Syncope during exertion or when supine
• Presence of a structural cardiac abnormality or coronary heart disease
• A family history of sudden death at young age
• Sudden onset palpitations immediacy followed by syncope
• Findings on ECG suggestive of arrhythmic syncope

Question 23

What are the 4 inital things you need to do when a patient presents with TLOC ?

Answer 23

1. A careful history
2. Full physical examination, including
3. Orthostatic blood pressure (BP) measurement
4. 12-lead ECG

After this Additional examination and investigations can then be planned based on the findings from the above

Question 24

What additional investigation may be added to the 4 other investigations when someone presents with TLOC with a history of previous known heart disease or data suggestive of structural heart disease or syncope secondary to cardiovascular cause.

Answer 24

Echocardiogram