The document discusses pediatric syncope, detailing definitions, differential diagnoses, and causes, particularly neurocardiogenic syncope as the most common type in children. It emphasizes the importance of distinguishing syncope from other conditions like seizures and highlights red flags for serious underlying cardiac issues. The evaluation and treatment approaches are outlined, stressing the need for proper history-taking and investigation, especially when symptoms suggest life-threatening conditions.

1. Approach to Syncope
in Children
(Pediatric Syncope)
By:-
Jwan Ali Ahmed AlSofi

2. Contents:-
• Introduction
• Differential diagnosis of syncope
• Syncope vs vertigo vs Presyncope vs light-headedness.
• Comparison of Clinical Features of Syncope and Seizures
• Neurocardiogenic (Vasovagal) syncope
• MECHANISMS and Causes of Syncope
• Cardiac causes of syncope
• Life-threatening causes of syncope
• Red Flags in Evaluation of Patients With Syncope
• Non-cardiac causes of loss of consciousness.
• Noncardiac Causes of Syncope
• Differentiating Features for Causes of Syncope
• EVALUATION of syncope:- History, Examination,Treatment.
• Summary
2

3. Introduction:-
•Syncope is defined as a sudden transient loss of
consciousness with inability to maintain postural tone
with spontaneous recovery requiring no resuscitative efforts..
• Presyncope or near-syncope has many or all of the
prodromal symptoms without loss of consciousness.
• Most syncopal events are relatively benign.
• The most common cause of syncope in the normal pediatric
population is Neurocardiogenic syncope aka (vasovagal
syncope, fainting).
• Approximately 30–50% of children will have had a fainting
episode before 18 yr of age.
• Syncope must also be distinguished from vertigo and ataxia.

4. The differential diagnosis for typical syncope includes:-
1. Seizure
1. Patients with epilepsy may have incontinence,
2. marked confusion in the postictal state
3. abnormal electroencephalograms (EEGs).
4. Patients are rigid rather than limp
5. may have sustained injuries.
6. Patients do not experience the prodromal symptoms of syncope (e.g., dizziness, pallor,
palpitation, and diaphoresis).
7. The duration of unconsciousness is longer than that typically seen with syncope (<1
minute).
2. Metabolic cause (hypoglycemia),
▫ The onset and recovery occur more gradually
▫ they do not occur during or shortly after meals.
3. Hyperventilation
▫ Hyperventilation  hypocapnia intense cerebral vasoconstriction syncope.
▫ It may also have a psychological component.
▫ The patient often experiences air hunger, shortness of breath, chest tightness, abdominal
discomfort, palpitations, dizziness, numbness or tingling of the face and extremities, and
rarely loss of consciousness.
▫ The syncopal episode can be reproduced in the office when the patient hyperventilates.
4. Atypical migraine
5. Breath holding.
6. Hysteria

5. Syncope and Dizziness

6. Comparison of Clinical Features of Syncope
and Seizures:-

7. • Although vasovagal type of syncope is very common in
adolescence and has an excellent prognosis, other causes for loss
of consciousness are more dangerous; thus syncope may be the
first sign of more serious conditions.
• Indeed, the occurrence of syncope may well be the pediatrician’s
best opportunity to diagnose a life-threatening condition
before the patient subsequently succumbs.
• The task of the clinician, therefore, is not only to counsel the
family and the patient concerning the common form, but also to
rule out a number of important life-threatening cardiac
problems.
• Before age 6 years, syncope is likely caused by
1. a seizure disorder
2. breath holding
3. cardiac arrhythmias.

8. Neurocardiogenic
(Vasovagal) syncope
8

9. Vasovagal syncope:-
• Is often triggered by a specific event or situation such as pain, medical
procedures, or emotional distress.
• Classically associated with a prodrome that includes
1. Diaphoresis
2. Warmth
3. Pallor
4. feeling lightheaded – The most common prodromal symptom is
dizziness.
• Following the prodromal features there will be loss of motor tone.
• This type of syncope is characterized by hypotension and bradycardia.
• Once in a horizontal position,
▫ consciousness returns rapidly, in 1-2 min
▫ Some patients may have 30 sec of tonic-clonic motor activities, which should
not be confused with a seizure.
• Postictal confusion only rarely occurs, and the rule is the occurrence of only
brief postictal tiredness with a subsequent remarkable ability to resume
planned activities.
• The physical examination is normal.

10. Triggered by
dehydration, heat,
standing for a long
time without
movement, hot
showers, the sight
of blood, pain,
swallowing,
vomiting, sudden
exposure to cold as
with cold water
immersion, and a
sudden episode of
stress
Initially,
pallor and
sweating
followed
by
blurring of
vision,
dizziness,
and
nausea
Then a
gradual
collapse
with loss
of
conscious
ness.
Conscious
-ness
returns
rapidly, in
1-2 min

11. • Vasovagal Syncope:-
▫ Prodromal features have an insidious onset and build up gradually,
often arising from a state of malaise when they precede syncope.
• Epilepsy:-
▫ When auras with similar features precede an epileptic seizure, such features
are usually sudden, short in duration, and followed by other
manifestations of complex partial seizures such as stereotyped
automatisms.
• Abdominal pain:-
▫ a common aura in temporal lobe epilepsy,
▫ Occurs in vasovagal syncope and can be a trigger or a consequence of that
process (intestinal vagal hyperactivity).
• Most children with vasovagal syncope have an affected first-degree
relative; reports demonstrate autosomal dominant inheritance at least
in some families.
• 10% of vasovagal syncope has Urinary incontinence
• 50% of vasovagal syncope has a brief period of convulsive jerks

12. MECHANISMS and
Causes of Syncope:-

13. • Syncope by whatever mechanism is caused by a lack of adequate
cerebral blood flow with
1. Loss of consciousness
2. Inability to remain upright.
Cerebral
hypoperfusion
Cardiac
Non-
cardiac

14. Primary cardiac causes of syncope
Arrhythmias:-
long QT syndrome
Wolff-Parkinson-White
syndrome (particularly with
atrial fibrillation),
Ventricular tachycardia (VT);
VT may be associated with
• Hypertrophic cardiomyopathy ,
• Arrhythmogenic cardiomyopathy,
• Repaired congenital heart disease,
• a genetic cause such as (CPVT).
Occasionally supraventricular
tachycardia.
Bradyarrhythmias
•sinus node dysfunction
•high-grade second- or third-degree
atrioventricular (AV) block.
•Patients with congenital complete AV block
may present with syncope.
Cardiac
obstructive
lesions:-
Critical
aortic
stenosis
Coronary artery
anomalies, such as
an aberrant left
coronary artery
arising from the
right sinus of
Valsalva.
Patients with
primary
pulmonary
hypertension or
Eisenmenger
syndrome.

15. Life-Threatening Cardiac Causes as Risk
With Syncope:-

16. Red Flags in Evaluation of Patients With Syncope
• Syncope with activity or exercise or
supine
• Syncope not associated with
prolonged standing
• Syncope precipitated by loud noise
or extreme emotion
• Syncope requiring CPR
• Absence of presyncope or
lightheadedness
• Injury with syncope
• Family history of:-
▫ Syncope,
▫ Drowning,
▫ Sudden death,
▫ Familial
• Ventricular arrhythmia
syndromes,* cardiomyopathy
• Anemia
• Other cardiac symptoms
▫ Chest pain
▫ Dyspnea
▫ Palpitations
• History of
▫ cardiac surgery
▫ Kawasaki disease
• Implanted pacemaker
• Abnormal physical examination
▫ Murmur
▫ Gallop rhythm
▫ Loud and single second heart sound
▫ Systolic click
▫ Increased apical impulse
(tachycardia)
▫ Irregular rhythm
▫ Hypo- or hypertension
▫ Clubbing
▫ Cyanosis

17. Non-cardiac causes of loss of consciousness
include:-
1. Epilepsy
2. basilar artery migraine
3. hysterical syncope
4. Pseudoseizures
5. Occasionally, patients with narcolepsy may present with syncope.
6. Hypoglycemia
7. hyperventilation.

18. Noncardiac Causes of Syncope:-

19. Differentiating Features
for Causes of Syncope

20. 1. NEUROCARDIOGENIC
• Symptoms after prolonged motionless standing, sudden
unexpected pain, fear, or unpleasant sight, sound, or smell;
pallor
• Syncope in a well-trained athlete after exertion (without heart
disease)
• Situational syncope during or immediately after
micturition, cough, swallowing, or defecation
• Syncope with throat or facial pain (glossopharyngeal or
trigeminal neuralgia)

21. 2. ORGANIC HEART DISEASE
(PRIMARY ARRHYTHMIA, OBSTRUCTIVE HYPERTROPHIC
CARDIOMYOPATHY, PULMONARY HYPERTENSION):-
• Brief sudden loss of consciousness, no prodrome,
▫ Cardiac syncope is usually sudden without the gradual onset and
symptoms that accompany vagal syncope.
• Syncope while sitting or supine
• Syncope with exertion
• Injury because of an episode of syncope
• History of palpitations
• History of heart disease
• Family history of sudden death

22. 3. NEUROLOGIC:-
• Seizures:
- Preceding aura,
- Post event symptoms lasting > 5 min (includes postictal state of
decreased level of consciousness, confusion, headache or paralysis)
- As a rule, children with a new-onset seizure disorder of
unclear etiology should get an electrocardiogram to rule out
LQT syndrome masquerading as a seizure disorder.
• Migraine: syncope associated with antecedent headaches with or
without aura

23. 4. OTHER VASCULAR:-
• Carotid sinus: syncope with head rotation or pressure on the
carotid sinus (as in tumors, shaving, tight collars)
• Orthostatic hypotension: syncope immediately on standing
especially after prolonged bed rest

24. 5. DRUG INDUCED:-
• Patient is taking a medication that may lead to
1. long QT syndrome,
2. Orthostasis
3. Bradycardia

25. 6. PSYCHIATRIC ILLNESS:-
• Frequent syncope
• somatic complaints
• No heart disease
• Syncope resulting from hysteria is not associated with injury and
occurs only in the presence of an audience.
• During these attacks the patient does not experience the pallor and
hypotension that characterize true syncope.
• The attacks may last longer (up to an hour) than a brief syncopal
spell.
• Episodes usually occur in an emotionally charged setting and are
rare before 10 years of age.

27. EVALUATION

28. • The most important goal in the evaluation of the new
patient with syncope is to diagnose life-threatening
causes of syncope so that these causes can be managed.
• Many patients presenting with sudden cardiac arrest
caused by conditions such as LQTS will have previously
experienced an episode of syncope, so the presentation
with syncope is an opportunity to prevent sudden death.

29. The most important tool in evaluation is a careful
history:-
• The characteristics of cardiac syncope differ significantly from the
prodrome seen in neurocardiogenic syncope.
• Several red flags can be identified that should lead the clinician to
suspect that the mechanism is a life-threatening cardiac cause rather than
simple fainting.
• The occurrence during exercise suggests an arrhythmia or coronary
obstruction.
• Injury because of an episode of syncope indicates sudden occurrence
with a lack of adequate prodromal symptoms and suggests an
arrhythmia.
• The occurrence of syncope while recumbent would be quite unusual
in a patient with neurocardiogenic syncope and therefore suggests a
cardiac or neurologic cause.
• Occasionally, a patient with syncope caused by a tachyarrhythmia will
report the sensation of a racing heart before the event, but this is
unusual.

30. A careful family history is essential in
evaluation of syncope.
• if there are first-degree relatives with inherited
syndromes, such as a LQTS or HCM, this should lead to more
specific evaluation of the patient.
• if relatives died suddenly at a young age without a clear
and convincing cause, inherited cardiac arrhythmias or
cardiomyopathies should also be suspected.

31. Patients with a history of heart disease,
especially cardiac repair, may have causes that
are specific to their repair:-
Sinus node dysfunction is common after the Senning or Mustard
procedure for transposition of the great vessels.
VT may be seen after repair of tetralogy of Fallot.
A patient with a history of septal defect repair should be evaluated
for the late occurrence of AV block.
patients with an implanted pacemaker should be evaluated for
pacemaker lead failure.

32. The physical examination may also
offer clues:-
• Patients with HCM as will patients with aortic stenosis may have:-
1. a prominent cardiac impulse
2. an ejection murmur,.
• The patient with primary pulmonary hypertension will have:-
1. a loud and single second heart sound
2. an ejection click
3. the murmur of pulmonary insufficiency.
• Scars from prior cardiac surgery and pacemaker implantation
would be evident.

33. Investigations:-
• All patients presenting with a first episode of syncope must have an ECG
obtained, looking primarily for
1. QT interval prolongation,
2. Preexcitation
3. ventricular hypertrophy
4. T-wave abnormalities
5. conduction abnormalities.
• Other tests that may be needed depending on the results of the initial
evaluation may include
1. echocardiography,
2. exercise testing,
3. cardiac MRI
4. 24 hr Holter monitoring.
• In patients for whom there is a strong suspicion of a paroxysmal
arrhythmia, an implantable loop recorder may be the most effective
means of diagnosis.

34. Investigations:-
• Additional tests to look for
▫ Anemia
▫ Hypoglycemia
▫ drugs of abuse
▫ other etiologies will be determined by the history and physical
examination.

35. Head-up tilt table test:-
• If patients with positional syncope have autonomic
symptoms (such as pallor, diaphoresis, or hyperventilation), a
tilt table test is sometimes performed by some centers.
(a) Vasovagal: an abrupt decrease in BP usually with bradycardia
leading to syncope
(b) Dysautonomia (or postural hypotension): a gradual decrease in
BP without an increase in heart rate, leading to syncope
(c) POTS: an excessive increase in heart rate to maintain an
adequate BP to prevent syncope
35

36. 36
Schematic drawing of changes in heart rate (HR) and systolic blood pressure
(BP) observed during the head-up tilt test. Thin arrows mark the start of
orthostatic stress. Large unfilled arrows indicate appearance of symptoms wit
changes seen in HR and BP. POTS, postural orthostatic tachycardia syndrome.

38. TREATMENT
38

39. Therapy for vasovagal syncope includes:-
• avoiding triggering events (if possible)
• fluid and salt supplementation
• if needed, midodrine – alpha-adrenergic agonist, vasopressor.
• Immediately after the event, the patient should remain supine
until symptoms abate to avoid recurrence.

40. Treatment for cardiac causes of syncope will
be determined by the diagnosis:-
• If a reentrant tachycardia (AVNRT, AVRT) is found, then a catheter
ablation is indicated.
• If bradycardia from AV block was the cause of the syncope, a
pacemaker may be warranted.
• Patients with syncope from medically refractory malignant arrhythmias,
as may be seen in HCM, LQTS, arrhythmogenic cardiomyopathy, or
CPVT, require an implantable cardioverter-defibrillator.
• Patients with structural heart disease (valvular disease or coronary
artery anomalies) should be referred for surgery.

43. Summary:-
• Syncope is the transient loss of consciousness and muscle tone
and is typically associated with an upright position, prodromal
symptoms, pale appearance, and brief loss of consciousness with
rapid return to normal state of consciousness.
• Syncope occurring during exercise or with associated cardiac
symptoms should be considered atypical until more extensively
evaluated.

44. Thanks