Vasovagal Syncope

Question 1

Syncope is the term used to describe a temporary loss of consciousness. All of the following are types of syncope, but which is most common?

1 - Cardiac syncope
2 - Vasovagal syncope
3 - Orthostatic hypotension
4 - Neurological syncope
5 - Hypoglycemia

Answer 1

2 - Vasovagal syncope

Question 2

A vasovagal episode (or attack) is caused by a problem with the autonomic nervous system regulating blood flow to the brain. Which nerve is involved in vasovagal syncope?

1 - vagus nerve
2 - phrenic nerve
3 - cardiac plexus
4 - pulmonary plexus

Answer 2

1 - vagus nerve

• Vagus nerve receives a strong stimulus, such as an emotional event, painful sensation, etc which stimulates the parasympathetic nervous system.
• Blood vessels vasodilate
• BP and cerebral blood flow drops causing hypoperfusion to the brain causing syncope

Question 3

Do patients remember what was happening prior to the syncope event?

Answer 3

• Yes

Important as this distinguishes from epilepsy, and the time prior to syncope is described as the prodrome

Question 4

Which of the following do patients who experience vasovagal syncope have prior to the episode?

1 - Hot or clammy
2 - Sweaty
3 - Heavy
4 - Dizzy or lightheaded
5 - Vision going blurry or dark
6 - Headache
7 - all of the above

Answer 4

7 - all of the above

Where possible a collateral history should be taken

Question 5

Which of the following is NOT a cause of primary syncope?

1 - Dehydration
2 - Cardiac Valve Dysfunction
3 - Missed meals
4 - Extended standing in a warm environment
5 - response to a stimuli (pain, emotions)

Answer 5

2 - Cardiac Valve Dysfunction
This is a form of secondary vasovagal syncope

Primary = no specific cause can be identified

Question 5

In vasovagal syncope are twitching, shaking or convulsions common?

Answer 5

• No

BUT can occur, so important to gain information relating to prior to, during and after event

Question 6

Which of the following is NOT a cause of primary syncope?

1 - Hypoglycaemia
2 - Dehydration
3 - Anaemia
4 - Infection
5 - Emotional stimuli
6 - Anaphylaxis
7 - Arrhythmias or Valvular heart disease
8 - Hypertrophic obstructive cardiomyopathy

Answer 6

5 - Emotional stimuli

Secondary syncope have an underlying cause that can be identified

Question 7

When trying to identify the cause of vasovagal syncope, which of the following are important?

1 - identify any trauma
2 - current / recent illness
3 - perform a neurological examination
4 - perform a cardiac examination
5 - lying and standing blood pressure
6 - all of the above

Answer 7

6 - all of the above

Question 8

If we suspect a cardiac cause of vasovagal syncope, which of the following is the most appropriate method to identify the cause?

1 - ECG
2 - Troponins
3 - N-terminal pro B-type natriuretic peptide (NT-proBNP)
4 - Echocardiogram

Answer 8

1 - ECG

• Arrhythmias are common causes of vasovagal syncope
• 24h ECG may be used if paroxysmal arrhythmias are suspected

Echocardiogram may be used if structural heart changes are suspected

Question 9

Which of the following would be the least useful marker in a patient with suspected vasovagal syncope?

1 - FBC
2 - glucose
3 - LFTs
4 - U&Es

Answer 9

3 - LFTs

Question 10

Managing vasovagal syncope is difficult, because often the cause cannot be identified. Are these more common in men or women?

Answer 10

• Women

Typically younger women, but they grow out of this

Question 11

Which of the following is NOT part of the supportive management given to patients with suspected vasovagal episodes?

1 - avoid dehydration
2 - avoid missing meals
3 - increase salt in the diet to help raise BP
4 - avoid standing still for long periods
5 - if prodrome begins, sit or lie down and eat

Answer 11

3 - increase salt in the diet to help raise BP