Syncope

Question 1

Causes of syncope

Answer 1

1. Cardiovascular–> 80%
2. Cerebrovascular causes–> 15%
3. Other–> 5%

Question 2

what are the cardiac causes of syncope

Answer 2

1. cardiac arrhythmia (electrical)–20%
   - -bradyarrhythmias
   - -tachyarrhythmias
   - -carotid sinus syndrome
2. reduced cardiac output (mechanical)
   - -outflow obstruction i.e aortic stenosis, hypertrophic cardiomyopathy, myxoma
   - -inflow obstruction to venous return
   - -myocardial
3. reflex/underfill–60%
   - -vasovagal
   - -orthostatic/postural hypotension
   - -situational

Question 3

what is the most common cause of syncope

Answer 3

reflex/underfill (cardiac)

• -vasovagal
• -orthostatic/postural hypotension
• -situational

Question 4

what are the cerebrovascular causes of syncope

Answer 4

carotid artery disease
TIAs
vertebral-basilar syndrome
high ICP

Question 5

what are the “other” causes of syncope

Answer 5

hypoxia
hypoglycemia
drugs
alcohol
panic disorder
hysteria
hyperventilation

Question 6

what to ask on history for syncope

Answer 6

details of event–> onset, progression, position, activity, LOC, head injury

associated symptoms–> dizziness, chest pain, palpitations, anxiety

previous history

review medical conditions

medications–any recent changes?

Question 7

what physical exams to do for syncope

Answer 7

complete CVS and neuro

Question 8

what investigations to do for syncope

Answer 8

routine blood work
ECG
holter
carotid dopplers
echo

Question 9

management of syncope

Answer 9

stabilize
IV fluids if needed
definitive treatment depends on cause