- 6 yr old boy is admitted with h/o syncope yesterday . he was standing in the school assembly. mother doesnot recollect previous h/o of similar illness. But child get too tired easily
- What are the common causes of syncope?
- what all points are to be stressed in history?
- what all are the important physical findings to note?
- Do we to do investigations for this child?
- What all d/d are to be considered in transient altered sensorium ?
DISCUSSION
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Syncope is the most common cause of t-AMS. It is characterized by rapid onset, shortduration, and spontaneous complete recovery.Syncope is usually benign
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Reflex syncope, the most common form, is rare in children younger than 10 years but then increases in incidence dramatically, with a peak around 15 years of age.
- Pathophysiologic classification of syncope
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1. Neurally mediated/reflex syncope (most common cause in children)
A. Vasovagal
a. Orthostatic stress (common trigger)
b. Other triggers (fear, pain, sight of blood)
B. Situational (cough, sneeze, defecation, micturition, postprandial, postexercise)
C. Atypical forms (without apparent trigger or atypical presentation)
2.Cardiac syncope
A. Arrhythmia as the primary cause
B. Structural/functional heart disease
3. Syncope caused by orthostatic hypotension (uncommon cause in children)
A. Autonomic failure (primary or secondary)
B. Drug induced (vasodilators, diuretics, phenothiazines, antidepressants)
C. Volume depletion (hemorrhage, diarrhea, vomiting)
- HISTORY
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An important distinction to make for the diagnostic workup is whether this event was true syncope and if so, was it a common, benign reflex syncope episode or amore ominous cause. Many of the children with cardiovascular disorder who go onto experience SCA have syncope or presyncope as a warning symptom. Identifyingthis small subset amongst all patients who present with syncope is difficult
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Syncope occurring during exercise is an ominous sign and warrants a high index of suspicion for underlying cardiac disease. A careful history of the event and details of the past medical and family history should eliminate most of the causes of cardiac syncope.
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Reflex syncope CLINICAL CLUES
1. Long history of recurrent syncope
3.TYOICAL TRIGGERS LIKE PROLONGED STANDING IN HOT CROWDED PLACE
2. Absence of heart disease
4. After exertion
5. With head rotation or pressure on carotid sinus (tight collars, shaving, backing up a car)
6. Associated with nausea or vomiting
7. Prodrome of lightheadedness, dizziness, diaphoresis, nausea, and tunnel vision
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Cardiac syncope: red flags
1. Presence of heart disease or previous cardiac surgery
2. Family history of hereditary cardiomyopathy or channelopathy (Box 2)
3. Sudden onset of palpitation, shortness of breath, or chest pain followed by syncope
4. Episodes during exertion, swimming, or supine
5. ECG abnormality
6. Episodes brought on by sudden startle or loud noise such as alarm clock (LQTS)
7. Acute or subacute history of febrile illness, exercise intolerance, or fatigue
(cardiomyopathy, myocarditis)
8. Abrupt syncope with no premonitory symptoms
9. Injury with syncope
10. Event triggers: extreme emotional stress (LQTS)
11. Young age at presentation (<10 years of age, especially <6 years of age)
12. Unexplained seizure in the past
C. Cardiac syncope: red flags in the family history
1. Sudden unexpected unexplained death at a young age (<30 years)
2. Unexplained fainting spells or seizures
3. Unexplained driving or drowning accidents
4. Sudden infant death syndrome
5. Congenital deafness
6. Hereditary cardiomyopathies (HCM, dilated cardiomyopathy, ARVD)
7. Hereditary channelopathies (LQTS, Brugada, CPVT, short QTS)
8. Pacemaker or defibrillator implants at a young age
9. Marfan syndrome
Clinical clues helpful in differentiating syncope from seizures
Syncope Seizure
Triggers Typical Rarely (flashing lights)
Prodrome/aura 1. Sweating and pallor 1. Rising sensation in abdomen
2. Nausea, vomiting, and 2. Smell
abdominal discomfort
3. Lightheadedness, blurring
Movements
1. Last few seconds, <15 s
2. Asynchronous 2. Synchronous
3. Nonrhythmical 3. Rhythmical
4. After fall and unconsciousness 4. Before fall
Flaccidity Often complete Unlikely
Tongue bite 1. Rare 1. Common
2. Middle 2. On the side
Recovery 1. Immediate clear headedness 1. Prolonged confusion
2. Nausea, vomiting and pallor 2. Muscle aches and headaches
Physical examination findings that indicate cardiovascular cause of syncope
- Key points to assess and to look for in physical examination
- 1. Heart rate and orthostatic BP
- 2. Sternotomy scar points toward past cardiac surgery, device pocket
- 3. Right ventricular heave with loud second heart sound suggest pulmonary hypertension
- 4. Gallop heard in dilated cardiomyopathy and congestive heart failure
- 5. Midsystolic murmur that increases in intensity with standing suggestive of HCM
- 6. Systolic murmur of aortic stenosis
- 7. Tumor plop of left atrial myxoma
- If the history and physical examination are typical for neurocardiogenic syncope and the ECG is normal, further testing generally is not needed.
- The single most clinically useful and cost-effective test to evaluate syncope is the 12-lead ECG.
Exercise stress testing is important in evaluating exertional syncope. An electrophysiology study may sometimes be indicated in patients with structural heart disease.
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ECG abnormalities to look for in a patient presenting with syncope
1. LVH, ST/T wave abnormality
2. Nonsustained VT
3. Wide QRS (left bundle branch block, right bundle branch block, bifascicular block,
intraventricular conduction delay)
4. Bradycardia, AV block, or prolonged pauses
5. Corrected QT interval to assess for LQTS, short QT syndrome
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6. d wave suggestive of WPW
7. Right bundle branch block 1 ST elevation in V1 to V3 (Brugada)
8. Negative T waves in right precordial leads and ε waves suggestive of arrhythmogenic right
ventricular cardiomyopathy
ventricular cardiomyopathy
9. Q waves suggesting myocardial infarction, HCM