Sinus or supraventricular tachycardia Albuterol Amphetamines Antidepressants Antihistamines Caffeine Cocaine Ephedra Energy drinks Ephedrine, pseudoephedrine Hallucinogens (e.g., lysergic acid diethylamide [LSD] or phencyclidine [PCP]) Herbal stimulants Marijuana Methcathinones (bath salts) and khat (Catha edulis leaves, popular in Africa and the Middle East) Phenothiazines Synthetic cannabinoids (e.g., K2 or Spice) Tobacco Ventricular tachycardia or torsades de pointes Amphetamines Antiarrhythmic agents (e.g., quinidine, procainamide, mexiletine, flecainide, encainide) Arsenic Caffeine Chloral hydrate Chlorinated hydrocarbons Chloroquine Cocaine Digoxin Organophosphate pesticides Phenothiazines Tricyclic antidepressants Bradycardia Calcium channel blockers Clonidine Digoxin Narcotics Organophosphate pesticides Sedative-hypnotic agents β-Adrenergic blockers EVALUATION AND DECISION The ill-appearing child with palpitations requires rapid assessment for the presence of hypoxemia, shock, hypoglycemia, or an existing lifethreatening arrhythmia Further evaluation should include measurement of hemoglobin, serum glucose, electrolytes, calcium, and pulse oximetry or blood gas The presence of heart disease should be ascertained by a 12-lead EKG and rhythm strip, followed by continuous monitoring, frequent vital signs, and chest radiograph ( Fig 63.1 ) Specific arrhythmias should be treated as outlined in Chapter 86 Cardiac Emergencies The asymptomatic child with palpitations by history may also have an intermittent or continuing arrhythmia Continuous cardiac monitoring and a resting 12-lead EKG performed while the patient is in the ED increase the likelihood that this abnormality will be detected Patients with repeated episodes of palpitations may benefit from 24-hour ambulatory (Holter) or longer-term event monitoring, and warrant referral to a pediatric cardiologist Any patient with a history of syncope, congenital heart disease, or particularly, postoperative or exercise-induced palpitations is at greater risk for having a true cardiac arrhythmia as the cause of his or her symptoms Similarly, the presence of a short P-R interval with the typical delta wave morphology of WPW syndrome or a prolonged corrected Q-T interval (see Chapter 86 Cardiac Emergencies ) indicates the need for evaluation by a pediatric cardiologist The presence or recent history of fever or an upper respiratory infection should prompt the emergency physician to look for signs and symptoms of myocarditis or acute rheumatic fever Myocarditis describes inflammation of the muscle wall of the heart Multiple organisms can cause this pathology, most commonly viruses such as coxsackievirus, Epstein–Barr, and cytomegalovirus Clinical features of myocarditis are fever, tachycardia out of proportion to activity or degree of fever, pallor, cyanosis, respiratory distress secondary to pulmonary edema, muffled heart sounds with gallop, and hepatomegaly caused by passive congestion of the liver EKG findings are nonspecific and include low-voltage QRS complexes (less than 5-mm total amplitude in limb leads), “pseudoinfarction” pattern with deep Q waves and poor R-wave progression in the precordial leads, AV conduction disturbances that range from P-R prolongation to complete AV dissociation, and tachyarrhythmias such as VT and SVT A child with palpitations and clinical findings suggestive of myocarditis requires emergent supportive care (see Chapters A General Approach to the Ill or Injured Child and 10 Shock ), echocardiography, consultation with pediatric infectious disease and cardiology, and admission to a unit capable of intensive monitoring and rapid treatment of cardiac arrhythmias and hemodynamic instability Acute rheumatic fever follows pharyngeal streptococcal infection and is an inflammatory disease that targets the heart, vessels, joints, skin, and central nervous system (CNS) Diagnosis and management of acute rheumatic fever are discussed separately (see Chapter 86 Cardiac Emergencies ) A detailed history of recent medications or precipitating events may reveal the cause of palpitations in some patients Ingestion of highly caffeinated beverages (i.e., coffee, soft drinks, energy drinks), cough and cold preparations, herbal preparations, dietary supplements, “health” drinks with herbal additives, use of illicit drugs, and a smoking/vaping history should be ascertained Similar to cigarettes, e-cigarettes, or vape products may contain highly concentrated nicotine and other substances that may cause palpitations The patient’s emotional state before the onset of palpitations should be discussed to determine the likelihood of anxiety or emotional arousal as the cause of symptoms (see Chapter 126 Behavioral and Psychiatric Emergencies ) The presence of diaphoresis, hypertension, and headache may prompt an assessment for pheochromocytoma, whereas widened pulse pressure and thyroid enlargement suggest hyperthyroidism (see Chapter 89 Endocrine Emergencies ) Anemia may be the cause of symptoms in a patient with pallor (see Chapter 93 Hematologic Emergencies ) In some patients, an exact cause of palpitations cannot be determined at the time of ED evaluation Patients with a single episode should have close follow-up arranged with their primary care physicians and should be instructed to return for further evaluation if symptoms recur Patients with multiple episodes of palpitations deserve further evaluation and consultation with a pediatric cardiologist ... indicates the need for evaluation by a pediatric cardiologist The presence or recent history of fever or an upper respiratory infection should prompt the emergency physician to look for signs... benefit from 24-hour ambulatory (Holter) or longer-term event monitoring, and warrant referral to a pediatric cardiologist Any patient with a history of syncope, congenital heart disease, or particularly,... General Approach to the Ill or Injured Child and 10 Shock ), echocardiography, consultation with pediatric infectious disease and cardiology, and admission to a unit capable of intensive monitoring