Syncope in Children
Objectives

Understand the term syncope

Differentiate the serious causes of syncope from
those that are benign

Know the appropriate testing needed in the
evaluation of syncope based upon the
presenting history
CONTINUITY CLINIC
Definitions to Know
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Palpitations - sensation of strong, rapid, or
irregular heart beats
Syncope – transient loss of consciousness and
postural tone due to generalized cerebral
ischemia with rapid and spontaneous recovery
Presyncope - no complete loss of
consciousness occurs
Syncope = syn(short) + kope (to cut)
CONTINUITY CLINIC
Syncope in children
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Affects 15% of children between 8-18
Uncommon under age 7 therefore think about:
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Seizure disorders
Breath holding
Primary cardiac dysrhythmias
Cardiovascular causes unusual but life-threatening
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anatomic abnormalities
congenital malformations
valvular disease
electrical abnormalities
CONTINUITY CLINIC
Syncope in children

Vasovagal Events
32% to 50% of cases
 Decreased PVR
 Decreased venous return
 Decreased cardiac output
 Hypotension
 Bradycardia
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In teens – think about pregnancy and drugs of
abuse
CONTINUITY CLINIC
Syncope: Key questions to address with
initial evaluation

Is the loss of consciousness attributable to
syncope or not?

Is heart disease present or absent?

Are there important clinical features in the
history that suggest the diagnosis?
CONTINUITY CLINIC
Syncope Mimics
 Disorders
without impairment of consciousness
Falls
Drop attacks
Cataplexy
Psychogenic pseudo-syncope
Transient ischemic attacks
 Disorders
with loss of consciousness
Metabolic disorders
Epilepsy
Intoxications
Vertebrobasilar transient ischemic attacks
CONTINUITY CLINIC
Differential Diagnosis of Syncope: Seizures vs Hypotension
Observation
Onset
Duration
Jerks
Headache
Confusion after
Incontinence
Eye deviation
Tongue biting
Prodrome
EEG
Seizure
Sudden
Inadequate
Perfusion
More gradual
Minutes
Frequent
Frequent (after)
Frequent
Seconds
Rare
Occasional (before)
Rare
Frequent
Horizontal
Frequent
Rare
Vertical (or none)
Rare
Aura
Often abnormal
Dizziness
Usually normal
CONTINUITY CLINIC
Causes of True Syncope
Orthostatic
Cardiac
Arrhythmia
Structural
CardioPulmonary
1
2
3
4
• Vasovagal
• Carotid Sinus
• Situational
• Drug-Induced
• Autonomic
Nervous
System
Failure
NeurallyMediated
Cough
PostMicturition
Primary
Secondary
• Brady
SN
Dysfunction
AV Block
• Tachy
VT
SVT
• Long QT
Syndrome
Unexplained Causes = Approximately 1/3
CONTINUITY CLINIC
• Acute
Myocardial
Ischemia
• Aortic
Stenosis
• HCM
• Pulmonary
Hypertension
• Aortic
Dissection
Likely Causes In Children

Vasovagal

Situational
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Psychiatric

Long QT*
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WPW syndrome
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RV dysplasia
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Hypertrophic cardiomyopathy
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Catecholaminergic VT
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Other genetic syndromes
CONTINUITY CLINIC
Syncope: Key questions to address with
initial evaluation

Is the loss of consciousness attributable to
syncope or not?

Is heart disease present or absent?

Are there important clinical features in the
history that suggest the diagnosis?
CONTINUITY CLINIC
Syncope: Important Historical
Features
Questions about circumstances just prior to attack
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Position (supine, sitting , standing)
Activity (rest, change in posture, during or immediately after
exercise, during or immediately after urination, defecation or
swallowing)
Predisposing factors (crowded or warm place, prolonged standing
post-prandial period) and of precipitating events (fear, intense
pain, neck movements)
Questions about onset of the attack
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Nausea, vomiting, feeling cold, sweating, pain in chest
CONTINUITY CLINIC
Syncope: Important Historical
Features
Questions about attack (eye witness)
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Skin color (pallor, cyanotic)
Duration of loss of consciousness
Movements ( tonic-clonic, etc.)
Tongue biting
Questions about the end of the attack
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Nausea, vomiting, diaphoresis, feeling cold, muscle
aches, confusion, skin color, wounds
CONTINUITY CLINIC
Syncope: Important Historical Feature
Questions about background
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Number and duration of syncope spells
Family history of arrhythmic disease or sudden
death
Presence of cardiac disease
Neurological disease
Medications (Hypotensive, negative chronotropic
and antidepressant agents)
CONTINUITY CLINIC
Clinical Features Suggesting Specific
Cause of Syncope
Neurally-Mediated Syncope
 Absence of cardiac disease
 Long history of syncope
 After sudden unexpected, unpleasant sensation
 Prolonged standing in crowded, hot places
 Nausea vomiting associated with syncope
 During or after a meal
 With head rotation or pressure on carotid sinus
 After exertion
CONTINUITY CLINIC
Clinical Features Suggesting Specific
Cause of Syncope
Syncope due to orthostatic hypotension
 After standing up
 Temporal relationship to taking a medication
that can cause hypotension
 Prolonged standing
 Presence of autonomic neuropathy
 After exertion
CONTINUITY CLINIC
Clinical Features Suggestion Cause of
Syncope
Cardiac Syncope
 Presence of structural heart disease
 With exertion or supine
 Preceded by palpitations
 Family history of sudden death
CONTINUITY CLINIC
Initial Exam: Thorough Physical
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Vital signs
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Cardiovascular exam: Is heart disease present?
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Heart rate
Orthostatic blood pressure change
ECG: Long QT, pre-excitation, conduction system disease
Echo: LV function, valve status, HCM
Neurological exam
CONTINUITY CLINIC
Orthostatic Measurements
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Classically, abnormal if systolic BP decreases by
more than 20 points and/or pulse increases in
pulse rate of more than 20 beats per minute
after a change from supine to standing
If there is only a pulse increase but no drop in
blood pressure, the test is less significant.
CONTINUITY CLINIC
Diagnostic Objectives
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Distinguish true syncope from syncope
mimics
Determine presence of heart disease and risk
for sudden death
Establish the cause of syncope with
sufficient certainty to:
Assess prognosis confidently
 Initiate effective preventive treatment
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CONTINUITY CLINIC
“…cardiac syncope can be a harbinger
of sudden death.”
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Survival with and
without syncope (adults
and children)
6-month mortality rate
of greater than 10%
Cardiac syncope
doubled the risk
of death
Includes cardiac
arrhythmias
CONTINUITY CLINIC
1.0
0.8
Probability of
Survival

0.6
No Syncope
Vasovagal/other
Cardiac Cause
0.4
0.2
0
5
10
Follow-Up (yr)
15
Soteriades ES, et al. N Engl J Med. 2002;347:878.
0.0
Electrocardiogram

yield for specific diagnosis low (5%)
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risk free and relatively inexpensive

abnormalities (BBB, previous MI, nonsustained
VT) guide further evaluation
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recommended in almost all patients
CONTINUITY CLINIC
Laboratory Tests
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Routine use not recommended
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Maybe glucose?
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Should be done only if specifically suggested by
H&P
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Pregnancy testing should be considered in
women of child-bearing age
CONTINUITY CLINIC
Neurologic Testing
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EEG - not useful unless seizures
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Brain imaging - not useful unless focality
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Neurovascular studies
no studies
 may be useful if bruits, or hx suggests
vertebrobasilar insufficiency
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CONTINUITY CLINIC
Final Words of Wisdom
-Is it Syncope?
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History is key!!!!
Orthostatics
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Cardiac vs Non-cardiac
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take the time to do them correctly
If you are not confident that it is NOT cardiac 
REFER
ECG
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Use it if you got ‘em!
CONTINUITY CLINIC