Syncope and Sudden Death

1. Syncope and Sudden Death

2. Syncope usually benign, but may represent serious cardiac problems. • Sudden death in peds d/t cardiac, neurologic, resp., and trauma. • Syncope is very common in adolescence. Most common cause neurally mediated syncope.

3. Sudden unexpected death include seizure, asthma, or toxic ingestion. • Sudden Cardiac death relates to cardiac dysfunction and is the most common cause of sports related deaths in children. • Most commonly d/t hypertrophic cardiomyopathy.

4. Syncope-sudden falling with brief LOC. Most experience a prodrome of lightheadedness or dizziness. • May have involuntary motor responses. • Sudden cardiac death is usually unexpected and unwitnessed.

5. Risk factors for serious cause of syncope. • Exertion preceding event • Cardiac disease • Family history of sudden death • Recurrent episodes • Recumbent episode • Chest pain/palpitations • On meds that alter cardiac conduction

6. Patient’s history and physical exam is important in identifying the cause of syncope. • Syncope during exercise is ominous. • Cardiac exam should include palpation of cardiac impulse, auscultation, eval of peripheral pulses. • Orthostatics identify volume depletion.

7. Cardiovascular, neuro, and pulmonary exams are often normal. • EKG is recommended for all pts. • Atypical or worrisome presentation should have cardiac panel, cbc, bmp, thyroid panel, cxr, alcohol, UDS.

8. Neurally mediated syncope includes vasovagal, vasodepressor, neurocardiogenic, reflex syncope and simple fainting. Considered benign. • NMS is the most common cause of syncope in children. • Last <1 min • Due to prolonged standing, emotional upset, sight of blood, physcial exertion, etc.

9. Orhtostatic- lightheadedness and weakness with standing. • Drop of 20 in SBP with increase of 20 BPM in HR. • Situational-urination, defecation, coughing, and swallowing. Due to carotid sinus hypersensitivity or valsalva response.

10. Cardiac dysrhythmias only seen in 3% of pediatrics with syncope. • Suspect if syncope occurs with fright, anger, surprise, or physical exertion. • Long QT syndrome is associated with hypertrophic cardiomyopathy, postive family history, and medications (Macrolides, TCA, antifungals, antihistamines, Trimethoprim, Quinolone). • If suspected, holter monitor should be placed.

11. Other cardiac dysrhythmias: • WPW • AV block • SSS • SVT

12. Structural Heart disease • Hypertrophic Cardiomyopathy- syncope is common presentation. In infant may present with CHF and cyanosis. • Dilated Cardiomyopathy • If diagnosed before 14, 50% 10 yr mortality rate. • Congenital cyanotic and non-cyanotic disease. • Valvular disease • Pulmonary HTN

13. Nonvascular causes • Seizures-associated with immediate convulsions, onset while supine and, prolonged postictal phase. • Breath holding-common in 6-18 month olds due to emotional upset • Atypical migraine • Hyperventilation • Hysteria • Hypoglycemia

14. Treatment • Child who survives cardiac arrest must be stabilized and PALS followed. • Unstable rhythms-cardiovert • Wide QRS tachydysrhythmias should not be treated with procainamide if LQTS is suspected. Use amiodarone instead.

15. Disposition • Admit pts with documented dysrhythmia. • Admit those with high risk factors • Treat any identified causes and admit. • Normal EKG but suspicious for dysrhythmia may be able to follow up for ambulatory cardiac monitoring

16. Pts with sudden cardiac arrest who survive should be transferred by appropriate crew to the nearest PICU.