syncope and cardiac arrest Flashcards
syncope?
Syncope is a transient, self limiting loss of
consciousness.
• Heralded by a sudden loss of postural tone
• Usually causing falling and some degree of injury
• Rapid onset
• Rapid spontaneous complete recovery
• Usually brief (<20 seconds)
• Secondary to transient global cerebral
hypoperfusion
common misdiagnosis?
Collapse with no alteration of consciousness
• Falls
• TIA
• Alteration of consciousness not loss of
conciousness
• Metabolic problems
• Epilepsy
• Intoxication
syncope vs seizures?
syncope - Tonic-clonic movements are always short
duration (<15s) and they start after the
loss of consciousness
vs
seizures -Tonic-clonic movements prolonged and
coincides with loss of consciousness
seizure
Hemilateral tonic/clonic movements
Automatism – chewing, lip smacking
head turning
Frothing at the mouth
Lateral tongue biting
Blue face
Prolonged confusion
syncope vs seizure
syncope - Nausea,vomiting,feeling cold,sweaty with
a pale complexion
vs
seizure - Nausea, aura or Déjà vu
syncioe vs seizure 3
Prompt recovery, nausea, vomiting,
pallor
vs
Prolonged confusion, muscle aches
seizures
Misdiagnosis of epilepsy is common
• Cerebral hypoperfusion results in myoclonic jerks
• Interictal EEG has low diagnostic yield
• A normal ECG is an important negative finding
• 4% of patients in Neurology OPD undergo an ECG
• Sudden Unexplained Deaths in Epilepsy (SUDEP)
• Excluding status epilepticus
• No cause found at post mortem
• 500 deaths/year in the UK
• Are these cardiac arrythmias?
neually mediated syncope?
Absence of cardiac disease
• Long history of syncope
• After unpleasant sight, sound, smell or pain
• Prolonged standing or crowded, hot places
• Nausea, vomiting associated with syncope
• During or in the absorptive state after a meal
• With head rotation, pressure on carotid sinus(as
in tumours, shaving, tight collars)
• After exertion
orthostatic hypotension?
•After standing up
•Temporal relationship with start of medication
leading to hypotension or changes of dosage
•Prolonged standing especially in crowded, hot
places
•Presence of autonomic neuropathy or Parkinsonism
•After exertion
cardiac syncope?
• Presence of severe structural heart disease
• During exertion
• Preceded by palpitation or accompanied by
chest pain
• Family history of sudden death
examination:
Heart failure
• Murmurs
• Orthostatic blood pressure measurement:
Five minutes lying flat – baseline
Standing – baseline
Every minute after standing for 3 minutes
(Before if symptoms)
Until blood pressure stops falling.
• >20mmHg drop or a decrease to <90mmHg
(regardless of whether symptoms occur)
where is the J wave?
between S and T.
symptoms and ECg correltation?
24 hr Holter Monitoring = 4% (40% asymptomatic
arrhythmia)
• Implantable Loop Recorder = 80%
(Shorter time to diagnosis)
how to record the arrythmias?
implantable loop recorder, provocation teting (provike the syncope)
head up titl table test
Head up Tilt Table Testing
• Carotid sinus massage
Limitations
• False positivity high
• False negativity also high
cardiac arrest?
Cardiac arrest is defined as the
sudden cessation of an effective
cardiac output.
• Electrical or mechanical
electrical cardiac arrest?
Tachycardias
– Ventricular Fibrillation
– Ventricular Tachycardia
ventricular arrhtymias
Potentially Reversible Causes
• Myocardial Ischaemia
• Drug Pro-arrhythmia
• Electrolyte disturbance
• Hypoxia
Structural Heart Disease
• Ongoing recurrent risk
asystole
Acidosis
• Hypoxaemia
• Hyper/hypokalaemia
• Hypothermia
• Drug overdose
– Calcium Antagonists
– Tricyclic Anti-depressants
