vasovagal syncope will most often have a normal ECG and reassuring physical examination Other Tests The patient with syncope should be placed on a continuous cardiac monitor to evaluate the heart rate and rhythm while in the ED Routine use of screening blood tests in unselected pediatric patients with syncope will have a very poor diagnostic yield Consider testing for hypoglycemia (via blood glucose), anemia (hemoglobin and hematocrit), pregnancy (urine pregnancy test), and recreational drugs (urine toxicology screen) in appropriate clinical scenarios Check the serum chemistry in patients suspected to have electrolyte problems such as hypokalemia or hypocalcemia Cardiac enzymes are not routinely recommended in pediatric patients with syncope However, they may be necessary in an adolescent with chest pain, or if the clinical evaluation suggests myocarditis or structural heart disease Echocardiography and Other Cardiovascular Testing The American Heart Association recommends the use of echocardiography only in patients with clinically suspected heart disease or exercise-induced syncope In the absence of a history of exercise-induced syncope, positive family history, abnormal physical examination, or abnormal ECG, the echocardiogram does not contribute to the routine evaluation of pediatric syncope However, the echocardiogram can identify underlying heart disease such as hypertrophic cardiomyopathy, aortic stenosis, or anomalous coronary arteries It may suggest pulmonary hypertension if significant tricuspid regurgitation or right ventricular enlargement is present Indications for an echocardiogram in a patient with syncope include known heart disease, pathologic murmur, evidence of chamber hypertrophy on ECG or chest radiograph, repolarization abnormalities with strain or ischemia, ventricular ectopy or concern for myocarditis, cardiomyopathy, or pulmonary hypertension Ambulatory ECG (Holter) monitoring may be useful if the screening ECG is normal but the history still suggests an arrhythmia as source of syncope, if there is exertional syncope, or if the relationship of a nonspecific ECG finding to symptoms is unclear An event recorder may be more practical because patients are able to keep the monitor for a month and activate it at the time of their symptoms The stress test may help in eliciting changes in QT intervals in patients with LQTS or arrhythmias in those with catecholaminergic polymorphic ventricular tachycardia (CPVT), but should be ordered by a cardiologist Exercise stress testing may be helpful in the diagnosis of channelopathies, such as LQTS and CPVT, which have adrenergically mediated arrhythmias The head-upright tilt table test (HUTT) may be used to provoke a hypotensive episode that mimics the patient’s symptoms However, it has low sensitivity, and current guidelines recommend it only in cases when the diagnosis of vasovagal syncope is truly unclear Pediatric patients with episodes of vasovagal syncope may exhibit convulsive movements during loss of consciousness that mimic epileptic seizures; HUTT may help in differentiating children with a primary seizure disorder A combined cardiology and neurology evaluation may be warranted in patients with syncope and seizure-like activity Additional indications for use of HUTT are recurrent syncope or exertional syncope in which heart disease has been ruled out, or recurrent syncopal episodes thought to be due to conversion disorder Neurologic Testing Neuroimaging is rarely required for a typical patient with syncope and the diagnostic yield is likely to be low The only indication for neuroimaging is for a patient with focal neurologic deficits or persistently altered mental status in whom it is necessary to rule out significant intracranial injury or cerebrovascular accident An electroencephalogram (EEG) may be performed on an outpatient basis if clinical features suggest a seizure and the patient has returned to a baseline neurologic status However, it is important to remember that a normal EEG does not rule out epilepsy TREATMENT Most children with syncope can be managed on an outpatient basis Patients with vasovagal syncope and their families will need reassurance and education about the benign nature of the condition They should be taught how to recognize prodromal symptoms and avoid precipitating factors such as dehydration, standing for prolonged periods, hot crowded environments, and diuretic intake Maneuvers to prevent venous pooling (such as keeping the knees slightly bent when standing for a long time, isometric contraction of extremity muscles, toe raises, folding of the arms, and crossing of the legs) or even assuming a seated or supine position may help Patients should be encouraged to increase their oral intake of water (up to L per day in an adolescent), to add salty snacks to their diet, and to avoid consuming caffeinated beverages If increased fluid and salt intake are not helpful, pharmacotherapy may be considered in patients with recurrent syncope TABLE 76.3 CONDITIONS THAT MAY REQUIRE HOSPITALIZATION IN PEDIATRIC SYNCOPE Abnormal cardiovascular examination and cardiovascular disease Drug-related syncope Attempted suicide Neurologic Persistently altered mental status Focal neurologic deficits Recurrent seizures Recurrent hypoglycemia Orthostatic hypotension resistant to fluid therapy Patients who require CPR CPR, cardiopulmonary resuscitation A variety of different medications have been tried in pediatric patients with recurrent syncope Of these, midodrine, an α-adrenergic agonist, has shown some of the most beneficial results in reducing symptom recurrence with few side effects Fludrocortisone, a mineralocorticoid, has also been used; however, its effectiveness is uncertain in pediatric patients with orthostatic hypotension associated with syncope Since symptoms of depression or anxiety are common in patients with recurrent syncope, management of potential mood disorders may be beneficial The treatment of POTS is challenging, and no one pharmacologic or nonpharmacologic approach has been consistently successful Recommendations include education, hydration with clear, no caffeinated beverages, increased salt intake, elevation of the head of the bed by 10 to 15 cm, and a gradual reconditioning exercise program spaced over months Patients with recurrent syncopal symptoms who not improve with conservative measures and pharmacotherapy, as well as those with a suspected cardiac cause for syncope, should be referred to a cardiologist for further management Some situations may warrant hospital admission or observation of a child with syncope ( Table 76.3 ), especially those involving persistent cardiovascular abnormalities or neurologic deficits For congenital LQTSs, the mainstay of therapy is the use of a long-acting beta blocker Because syncope in these patients is adrenergically mediated, they are restricted from athletic activity The use of an implantable cardioverter- defibrillator (ICD) is considered in a subgroup of patients felt to be at high risk for sudden death, such as those with symptoms before puberty, very long QT intervals (>500 msec), and those with recurrent syncope The use of an ICD is also required in patients with hypertrophic cardiomyopathy and Brugada syndrome Adult survivors of congenital heart disease should be cared for by health providers knowledgeable in the anatomy, repair, and management of these conditions SUMMARY POINTS Syncope is a common condition in children and is usually benign Common causes for syncope include vasovagal syncope, breath-holding spells, and orthostatic intolerance Life-threatening causes are usually cardiac in etiology A comprehensive medical and family history, a thorough physical examination, and a 12-lead ECG will help identify most patients with life-threatening causes of syncope Routine blood testing and imaging are unnecessary Since recurrence is common, education and reassurance are important Suggested Readings and Key References Goldenberg I, Moss AJ, Peterson DR, et al Risk factors for aborted cardiac arrest and sudden cardiac death in children with the congenital long-QT syndrome Circulation 2008;117:2184–2191 Morrow W, Berger S, Jenkins K, et al Pediatric sudden cardiac arrest Pediatrics 2012;129:e1094–e1102 Roden DM Long-QT syndrome N Eng J Med 2008;358:169–176 Sheldon RS, Grubb BP 2nd, Olshansky B, et al 2015 Heart Rhythm Society expert consensus statement on the diagnosis and treatment of postural tachycardia syndrome, inappropriate sinus tachycardia, and vasovagal syncope Heart Rhythm 2015;12:e41–e63 Shen WK, Sheldon RS, Benditt DG, et al 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines and the heart rhythm society Circulation 2017;136(5):e60– e122 ... long-QT syndrome Circulation 2008;117:2184–2191 Morrow W, Berger S, Jenkins K, et al Pediatric sudden cardiac arrest Pediatrics 2012;129:e1094–e1102 Roden DM Long-QT syndrome N Eng J Med 2008;358:169–176... considered in patients with recurrent syncope TABLE 76.3 CONDITIONS THAT MAY REQUIRE HOSPITALIZATION IN PEDIATRIC SYNCOPE Abnormal cardiovascular examination and cardiovascular disease Drug-related syncope... require CPR CPR, cardiopulmonary resuscitation A variety of different medications have been tried in pediatric patients with recurrent syncope Of these, midodrine, an α-adrenergic agonist, has shown