Syncope in Children

1. Syncope in Children

2. 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

3. Definitions to Know • 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)

4. Syncope in children • Affects 15% of children between 8-18 • Uncommon under age 7 therefore think about: • Seizure disorders • Breath holding • Primary cardiac dysrhythmias • Cardiovascular causes unusual but life-threatening • anatomic abnormalities • congenital malformations • valvular disease • electrical abnormalities

5. Syncope in children • Vasovagal Events • 32% to 50% of cases • Decreased PVR • Decreased venous return • Decreased cardiac output • Hypotension • Bradycardia • In teens – think about pregnancy and drugs of abuse

6. 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?

7. 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

8. Differential Diagnosis of Syncope: Seizures vs Hypotension

9. Causes of True Syncope Neurally- Mediated Orthostatic Cardiac Arrhythmia Structural Cardio- Pulmonary • 1 • Vasovagal • Carotid Sinus • • Situational • Cough • Post- Micturition • 2 • Drug-Induced • • Autonomic Nervous System Failure • Primary • Secondary • 4 • Acute Myocardial Ischemia • Aortic Stenosis • HCM • Pulmonary Hypertension • Aortic Dissection • 3 • Brady • SN Dysfunction • AV Block • • Tachy • VT • SVT • Long QT Syndrome UnexplainedCauses = Approximately 1/3

10. Likely Causes In Children • Vasovagal • Situational • Psychiatric • Long QT* • WPW syndrome • RV dysplasia • Hypertrophic cardiomyopathy • Catecholaminergic VT • Other genetic syndromes

11. 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?

12. Syncope: Important Historical Features Questions about circumstances just prior to attack • 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 • Nausea, vomiting, feeling cold, sweating, pain in chest

13. Syncope: Important Historical Features Questions about attack (eye witness) • Skin color (pallor, cyanotic) • Duration of loss of consciousness • Movements ( tonic-clonic, etc.) • Tongue biting Questions about the end of the attack • Nausea, vomiting, diaphoresis, feeling cold, muscle aches, confusion, skin color, wounds

14. Syncope: Important Historical Feature Questions about background • 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)

15. 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

16. 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

17. 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

18. Initial Exam: Thorough Physical • Vital signs • Heart rate • Orthostatic blood pressure change • Cardiovascular exam: Is heart disease present? • ECG: Long QT, pre-excitation, conduction system disease • Echo: LV function, valve status, HCM • Neurological exam

19. Orthostatic Measurements • 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.

20. Diagnostic Objectives • 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

21. 1.0 0.8 0.6 0.4 0.2 0.0 Probability of Survival No Syncope Vasovagal/other Cardiac Cause 0 5 10 15 Follow-Up (yr) “…cardiac syncope can be a harbinger of sudden death.” • 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 Soteriades ES, et al. N Engl J Med. 2002;347:878.

22. Electrocardiogram • yield for specific diagnosis low (5%) • risk free and relatively inexpensive • abnormalities (BBB, previous MI, nonsustained VT) guide further evaluation • recommended in almost all patients

23. Laboratory Tests • Routine use not recommended • Maybe glucose? • Should be done only if specifically suggested by H&P • Pregnancy testing should be considered in women of child-bearing age

24. Neurologic Testing • EEG - not useful unless seizures • Brain imaging - not useful unless focality • Neurovascular studies • no studies • may be useful if bruits, or hx suggests vertebrobasilar insufficiency

25. Final Words of Wisdom-Is it Syncope?- • History is key!!!! • Orthostatics • take the time to do them correctly • Cardiac vs Non-cardiac • If you are not confident that it is NOT cardiac  REFER • ECG • Use it if you got ‘em!