Adolescent Syncope Brett Goudie, M.D. Pediatric Cardiology Case 1 – Altar Boy • 14 yo boy presents to clinic following syncopal episode. Standing in church, felt hot and lightheaded before passing out. Witnessed event, parents described brief seizure like activity while he was down. No loss of bowel or bladder control, no CPR, no resp support. Brief LOC, woke up 5 sec later, was soon back to being alert and oriented. He noted visual changes and hearing became distant prior to the episode. • Cause? • Further testing? • Referral? • Recommendations? • From the Greek word synkoptein, which means “to cut short” • Syncope – “temporary loss of consciousness and postural tone resulting from an abrupt, transient, and diffuse cerebral dysfunction (hypoperfusion), and followed by spontaneous recovery” – cerebral blood flow ↓ 30-50% Syncope • Syncopized???? • Pre-syncopize? • Pre-syncope – prodromal dizziness and lightheadedness that precedes LOC – aka near-syncope • Sadly I have no financial disclosures related to this topic Case 2 – Track Star • 17 yo girl (no PMHx) presents after syncope with exercise. She was running the 100 m dash, and passed out suddenly while running. No preceding symptoms. Woke up 4-5 sec later, was confused, had trouble recognizing her track coach or track team. • Same questions • Cause? • Further testing? • Referral? • Recommendations? Syncope – why talk about it? • Common - 15-25% of children experience at least one episode (peak ages 15-19) (♀ > ♂) • Expensive clinical problem / testing / Up to 3 % of ER visits / treatable • Most pediatric syncopal episodes are totally benign • 80-90% is vasodepressor or cardioinhibitory → vasovagal • Only 1% of time due to arrhythmia or structural cardiac disease – hence there is a risk of sudden death • ANGST!!!!! Vasovagal Syncope Terminology • Vasodepressor (Vaso) • Cardioinhibitory (Vagal) • Neurocardiogenic • POTS – postural orthostatic tachycardia syndrome • Orthostatic Hypotension or Intolerance • Situational • Reflex • Neurally mediated • Dysautonomia Bryan Cannon, Philip Wackel Pediatrics in Review Apr 2016, 37 (4) 159-168 “Fainting Goat” Myotonia Congenita Presyncope • Lightheaded, dizziness • Visual changes - blurry vision, tunnel vision, spots, double vision • Altered hearing – distant voices • Altered mentation, confusion, panic, h/a • Weakness, poor balance • Warmth / rush, or cold and clammy • Sweating, nausea • Pallor or gray Syncope, at the Carotid Sinus • Upright posture, 25% of blood redistributed to lower extremities • Preload diminished, leads to diminished stroke volume by as much as 40%, CO = HR * SV • Baroreceptors activated (Carotid sinus) • Increased sympathetic activity increases HR, contractility, and SVR (systemic vascular resistance) • Failure of this response leads https://medicine.uiowa.edu/iowaprotocols/ca to vasodepressor syncope rotid-body-and-carotid-sinus-general- information Bezold-Jarisch Reflex Tilt Venous Return Vagal Efferent HR BP Vagal BP Reflex Afferent Brain Syncope Ventricles Stem Carotid Sinus Vasodilation Baroreceptors Sympathetic Withdrawal Catecholamines Increase HR, contractility, and BP Chang-Sing P. Cardiol Clinics. 1991;9(4):641-651. Albert von Bezold (1836-1868) • "Bezold-Jarisch reflex" is a triad of responses (bradycardia, hypotension, and apnea) from paradoxical stimulation of vagal mediated ventricular C fiber receptors. • Reflex is involved with the “Cardioinhibitory” or “Neurocardiogenic” Syncope • Bezold - intravenous injection of veratrum alkaloids, +/- vagal nerve ligation. Bezold – died from rheumatic Bezold - Munich, then in Univ of Berlin under disease, had both du Bois-Reymond (nerve action potential) arthritis and carditis (mitral • Adolf Jarisch Jr (1891–1965) replicated study stenosis), died at in cats with reversible cooling of vagal nerve. 32 Veratrum viride or album • Potent alkaloids, antagonism of adrenergic receptors • Highly toxic – nausea / vomiting, cold sweat and vertigo, slowing of respiration, bradycardia, hypotension, death • 1950-1960s extract known as alkavervir – antihypertensive • Some Native American nations – historical use for elections of new leader Bezold-Jarisch Reflex Tilt Venous Return Vagal Efferent HR BP Vagal BP Reflex Afferent Brain Syncope Ventricles Stem Carotid Sinus Vasodilation Baroreceptors Sympathetic Withdrawal Catecholamines Increase HR, contractility, and BP Chang-Sing P. Cardiol Clinics. 1991;9(4):641-651. History / Physical Exam / EKG • What are the circumstances leading to events? Sick with URI or other illness pre or post? Preceding mono or viral illness weeks or months prior? Growth spurt? • Abrupt onset or prodrome? Exercise? Post trauma? • Are there palpitations, visual changes, chest pain, shortness of breath, dizziness vs vertigo? • LOC details – duration? • Injury? Seizure? Loss of bowel/bladder control? CPR? • Eat or drink? Is there a history of caffeine use? Is his/her urine concentrated or clear? 2nd daily void Syncope after surprise, loud noises, anger No warning or while supine Prodrome of palpitations/tachycardia/severe chest pain Syncope Syncope with exercise *** History – Red Prolonged down time, pulseless, Flags CPR, residual neuro issue Other red flags Abnormal exam or EKG F Hx of sudden death / SIDS Hx of CHD Adult Syncope – more likely to be cardiac Benign Prodrome Brief Episode Single Episode Only while Upright Syncope Change of position History – Poor hydration Lots of dizziness with standing Green Flags OR Presyncope only – no flaccid LOC, full memory Family History / Physical Exam / EKG • Arrhythmias • Sudden death • SIDS • Cardiomyopathy • Pacemakers • Defibrillators / ICD • Deafness • Congenital Heart Disease • Fainters History / Physical Exam / EKG • Heart rate and blood pressure, both supine and standing, then standing again in a few minutes • Are the first and second heart sounds normal? • Is there a murmur? Does it get louder with standing? • Any ectopy noted? • Is there a click, gallop, rub, or filling rumble? • Leg plethora, edema, swelling Bryan Cannon, Philip Wackel Pediatrics in Review Apr 2016, 37 (4) 159-168 Bryan Cannon, Philip Wackel Pediatrics in Review Apr 2016, 37 (4) 159-168 Bryan Cannon, Philip Wackel Pediatrics in Review Apr 2016, 37 (4) 159-168 • Pseudoseizures or behavioral spells • no physiologic changes prior to syncope • Certain times, certain places, daily • > age 10. LOC > 10 min • Emotionally charged • Common after abuse (emotional or Psychogenic sexual) • 15 yo girl “passing out” many times Syncope per day. • Fluid, salt, cut caffeine • Florinef, mitodrine. • Put on the brakes BP high. • Episode during stress test, actually passed out with no BP change, no EKG change, nothing. No EKG change ????? Fainting Lark History / Physical Exam / EKG • Is the rhythm SINUS? • Is the rate appropriate? • Is there AV block? • Is there evidence of hypertrophy or strain? • Is there pre-excitation (short PR or delta)? • Is the QTc normal? • Any PVCs? EKG post syncope Diagnostic tests • Orthostatic HR and BP • ECG • Head Up Tilt Test - usually not necessary • Exercise stress test – syncope with exercise • 24 hour Holter / 30 day event/loop monitor / Reveal monitor • Echocardiogram with emphasis on chamber size, obstructive lesions, coronary arteries • Electrophysiology study • Labs – U/A (spec grav), CBC, glucose, Lytes, TSH, pregnancy, drugs • Brain imaging – only for focal neuro signs • EEG – can be abnormal after benign syncope The Tilt Lab Neurally-Mediated Syncope Tilt Table Response Sra JS. Ann Intern Med. 1991;114:1013-1019. Arrhythmias Causing Syncope • Bradycardia • Sinus Node Dysfunction • AV Block • Tachycardias • Wolff-Parkinson-White Syndrome • Long QT Syndrome • Brugada Syndrome • Arrhythmogenic RV Dysplasia (ARVD) • Catecholaminergic Polymorphic VT (CPVT) Sinus Node Dysfunction • Inappropriately slow (or fast) heart rate • SA node origin • Frequently seen in post-op hearts • <3 years old <100 • 3-9 years old <60 • 9-16 years old <50 • >16 years old <40 Complete AV Block Wolff-Parkinson-White Syndrome Not-so-subtle WPW Atrial Fibrillation in WPW The Long QT Syndrome • LQTS is present in 1:5,000 persons (over 50,000 people) in the USA • Estimated to cause as many as 3000 deaths (mostly in children and young adults) in the USA each year. • It is present in all races and ethnic groups • In as many as 30-40%, sudden death is the first event (8-40% of asymptomatic patients have SCD as first event) • 57% of patients who die will die by age 20 • Events rates are 5%/yr. for syncope and 0.9-2.5%/yr. for cardiac death Corrected QT Interval (QTc) • Include U wave if > 50% of T wave height • Upper limits of normal 450 PPV 100% Male >470 Female >480 PPV 93% >460 NPV 100% Male <400 Female <420 Torsades de Pointes ECG Phenotype of LQT3, 2, and 1 LQT3 LQT2 LQT1 Varieties of LQTS • LQT 1-Tend to have events at times of exertion or excitement. • LQT 2-Tend to have events when startled or with swimming. • LQT 3-Tend to have events when asleep. • LQT 1 and 2 account for 85% of total. LQT 3 accounts for about 10%. TdP following a sudden arousal (alarm clock) in a patient with a HERG defect. Wilde et al. JACC. 1999;33:327-32 Treatment of LQTS • Avoid all strenuous exercise, esp. swimming • Avoid startling (alarm clocks etc.) • Beta blocker therapy (Propranolol, Nadolol) w/ or w/o bradycardia pacing • ICD (QTc>550, noncompliant, FHx SCD) • Left Stellate ganglionectomy Drugs – QTDRUGS.ORG Brugada Syndrome • Leading cause of death in young Asian males • Arrhythmias tend to occur during febrile periods (exercise) and during sleep •