Syncope Flashcards
What is difference between loss of consciousness and syncope
Loss of consciousness can be divided into syncopal and non syncopal causes
Syncope refers to cutting of perfusion between heart and brain
What can syncope be classified into
Cardiac
Reflex
Orthostatic
Cerebrovascular
What happens in reflex syncope
Believed to be due to primitive reflex to play dead where in scary situation BP and HR temporarily
What are cerebrovascular causes of syncope
Non cardiac structural causes of loss of brain perfusion Aortic dissection Subclavian steal syndrome Vertebrobasilar insuffiency TIA
What causes orthostatic syncope
When stand there is sudden drop in BP that compensate for by vasoconstriction particularly the veins in the leg
What are reflex causes of syncope
Vasovagal
Carotid sinus hypersensitivity
Situational syncope
What causes straining syncope
For example in peeing and pooing your BP doesnt adapt in time
Cardiac causes of syncope
Arrythmias Aortic stenosis HCM HB PE
What causes orthostatic syncope
Drugs- anti-sympathetics, anti-hypertensives
Dehydration
Autonomic instability
Baroreceptor dysfunction
Who does baroreceptor dysfunction occur in
HTN- fail to accurately control BP
What is described before a vasovagal episode
Odd sensation in stomach Pallor Sweaty Nausea Knowing going to fall
What does syncope while playing sport/exercising suggest
HOCM
Aortic stenosis
Long QT
What does just sitting down or watching tele before syncope suggest
Arrythmia
Most common cause of syncope in the elderly
Orthostatic due to medications
What medications can cause syncope and how
Diuretics- fluid loss
ACEi- fluid loss and vasodilation
Beta blockers- failure to increase HR and BP on standing
A blockers- inability to constrict vessels in legs
CCB- inability to vasoconstrict and some affect heart
What is main concern of syncope in the elderly
Leads to morbidity- broken bones, loss of confidence, loss of independance etc
Leads to mortality- bleeds in brain, VTE and infections from prolonged bed rest
Cost of adapting house to new circumstances or affording to go into nursing home
What does syncope with no warning suggest
Cardiac
Cerebrovascular ie subclavian steal
Important questions to ask about before syncope
Warning Sx?
What doing at the time?
Head injury recently?
What is significant about recent head injury in syncope
Subdural bleed
Causes of non-syncopal blackout
Intoxication Head trauma Metabolic-hypoglycaemic, HHS, DKA Epileptic seizure Psycogenic seizure Narcolepsy
History of IHD in syncope
Ischaemia- HB, arrythmia
Medications- orthostatic
How long do arrythmia syncopes last
Seconds
What to ask about for during seizure
Tongue biting- epilepsy
Twitching and incontinence- not necessarily can also be arrythmia and vasovagal
Questions to ask about after syncope
Confused or weakness- seizure
How long to recover and how?
Syncope that lasted minutes
Seizure
Continuous similar episodes of syncope
Epilepsy
Syncope followed by weakness in arm
Todds paresis
TIA
How can diabetes lead to syncope
Polyuria-> orthostatic
Vascular disease predisposed
Autonomic dysfunction
Hypoglycaemia
How is psyciatric illness relevant to syncope
Predisposes to non-epileptic seizures
Significance of drug history syncope
Insulin and T2DM hypoglycaemics Antihypertensives Vasodilators Antiarrythmics Antidepressants Warfarin
Why are antiarrythmics significant in syncope history
Paradoxically predispose to arrythmias
Why are antidepressants significant in syncope history
TCAs cause hypotension
Why is warfarin or DOACs significant in syncope history
Increase likelihood of subdural bleed following trauma
Significance of recreational drugs in syncope
Coacaine arrthymias
Significance of alcohol in syncope history
Subdural predisposition
LOC leading to bleed
Importance of family history syncope
Sudden death in under 65 may have been caused by Long QT, WPWS and HOCM
What to look for in examination of syncope
Tongue bitten- epilepsy Pulse and obs- heart problems Dehydration status- orthostatic Heart murmur- HCM or aortic stenosis Focal neurology signs- ICP from bleed or tumour causing seizure
Investigations for syncope
Bloods- glucose, U&Es, FBC ECG Holter potentially CT/MRI if epilepsy indicated Echo if heart implied
Why do FBC syncope
Anaemia can be contributing factor
Why do glucose syncope
DM predisposes to cardiac problems and hypos
Why do U&Es
Urea in absence of creatinine is dehydration
Electrolyte imbalance predisposing to long QT
Why is history of mental health significant in blackout
TCAs cause hypotension
Predisposed to non epileptic
What does history of non stereotyped and inconsistent blackout stories suggest
Non epileptic seizures
History of BPH in syncope
On alpha blockers causing impaired vasoconstriction
What is stokes adams attack
When LOC due to complete HB
What happens if stokes adams attack occurs for more than 15 seconds
Twitching due to brain anoxia
What happens after a stokes adams attack
Facial flushing as flow returned to face
How can partial seizures be classsified by lobe based on sx
Frontal- motor
Parietal- sensory
Occipital- visual problem
Temporal- deja vu, smells/sounds aura
Which heart block is common in fit younger people
Mobitz T1
What can be investigation for vasovagal syncope
Tilt table test
What happens in tilt table test
Patient laid supine and moved about- posiive test if experience LOC with drop in HR and BP or they experience some symptoms related to vasovagal episodes
What is the main problem with anticonvulsant medications
Theyre teratogenic
Syncope brought on by using arm for a long time
Subclavian steal syndrome
Syncope brought on when putting tie on
Carotid sinus hypersensitivity
What is carotid sinus hypersensitivity
When the carotid sinus exaggerates response to pressure on it
What is test for carotid sinus hypersensitivity
Carotid sinus massage while attached to cardiac monitor with IV cannula in place in case go into cardiac arrest instead of syncope
What is brugada syndrome
Autosomal dominant condition with mutation in calcium sodium channel gene leading to RBBB and ST elevation in V1-V3 predisposing to ventricular dysrythmias
ECG changes in brugada syndrome
RBBB and ST elevation in V1-V3
How to tell from lying vs standing BP if cause is hypovolaemic or autonomic dysfunction
In hypovolaemia will be associated tachycardia whereas in autonomic dysfunction will be the same
