Syncope and Sudden Death in Children

Syncope and Sudden Death in Children Tintinalli Chap. 140

Syncope • Usually a benign process • Can be a symptom of serious cardiac disease and predispose to sudden death • Between 20-50% of all adolescents have at least one episode • Neurally mediated (vasovagal) is most common

Sudden Unexpected Death • 2.3% of all deaths • Sudden cardiac death • 1/3 of all unexpected deaths (600/yr) • 2nd most common cause of sports-related death in young athletes • Hypertrophic cardiomyopathy and myocarditis • Risk factors include structural heart disease, cardiac dysfunction, rhythm disturbances, and Marfan syndrome

Types of Syncope • Vascular syncope • Venous pooling in legs leads to decrease in ventricular preload • Neurally mediated syncope • Receptors in atria, ventricles, and pulmonary arteries sense decreased venous return triggering vagal response • Cardiac syncope • Interruption of cardiac output due to intrinsic cardiac abnormality

Neurally Mediated Syncope • Most common • Usually preceded by sensation of warmth, nausea, lightheadedness, and visual grayout/tunneling of vision • Usually lasts < 1 minute • Can occur with swallowing, urination, defecation, and coughing

Neurally Mediated Syncope • Precipitating Factors • Prolonged recumbence before standing • Sight of blood/injury • Emotional upset • Mild trauma/pain • Physical exertion • Hot/crowded conditions • Other Factors • Hypovolemia (diuretics in wrestlers) • Anemia • Dehydration • Pregnancy • Medications (beta blockers, CCB’s, diuretics)

Breath-Holding Spells • Typically 6-18 months • Precipitated by intense emotional trigger causing crying then breath-holding during expiration • Child becomes cyanotic or pale and loses consciousness • Myoclonic/seizure activity may occur • Rapidly resolves with gasping respirations and restoration of normal color

Cardiac Syncope Cardiac Dysrhythmias Structural Cardiac Disease Hypertrophic Cardiomyopathy Dilated Cardiomyopathy Right Ventricular Dysplasia Congenital Heart Disease Valvular Disease Pulmonary Hypertension Coronary Artery Abnormalities • Long QT syndrome • Wolff-Parkinson-White syndrome • AV block • Sick Sinus syndrome • SVT • Pacemaker malfunction

Long QT syndrome • Inherited • Rare • Associated with hypertrophic cardiomyopathy • Accounts for up to half of sudden cardiac death • Acquired • Medications • Antibiotics (Macrolides, Fluoroquinolones, Bactrim) • TCA’s • Antipsychotics • Antifungals • Antiarrhythmics

Clinical Features • Falling with brief LOC • Prodrome in 2/3 • Involuntary motor movements

Risk Factors • Exertional • History of cardiac disease • Family history of sudden death • Recurrent episodes • Recumbent episodes • Prolonged LOC • Chest pain or palpitations • Medications

Differential • Basilar migraine • Seizure • Vertigo • Hyperventilation • Hysteria • Hypoglycemia • Breath-holding spell

Diagnostics • EKG for nearly every child • CBC • BMP • Thyroid function tests • CXR • Urine drug screen • Serum alcohol level

Treatment • IV, O2, monitor • PALS protocol if unstable

Disposition • Admission • Dysrhythmia • Presence of Risk factors • Discharge • Negative history, physical exam, and workup • Most children without cardiac risk factors or exercise-induced symptoms

Syncope and Sudden Death in Children