Management of acute supraventricular tachycardia in children

Abstract

Question Recently, a 3-year-old patient in my practice urgently needed to go to the emergency department. The patient was found to have supraventricular tachycardia (SVT) and needed immediate treatment with adenosine. What evidence is currently available for management of SVT in children?Answer Supraventricular tachycardia is a common cardiac condition in the pediatric population that manifests as a narrow QRS complex tachycardia on electrocardiography. Symptoms may range from palpitations, poor feeding, and irritability to more substantial hemodynamic instability. Patients who are hemodynamically stable can benefit from interventions such as vagal maneuvers, which can be done in the office. Such maneuvers include the Valsalva maneuver, stimulation of the diving reflex (for infants), and unilateral carotid sinus massage. Other children may need pharmacologic therapies to restore normal heart rhythm, which usually consists of a rapid intravenous injection of adenosine under monitoring. For patients who are hemodynamically unstable, emergency cardioversion may be needed. Supraventricular tachycardia (SVT) is a relatively common cardiac condition in the pediatric population, with an incidence of 1:250 to 1:1000 in otherwise healthy children. 1 Supraventricular tachycardia is a group of rhythmic disturbances in which electrical impulses originating from any point proximal to the atrioventricular (AV) bundle result in a narrow QRS complex tachycardia (normal QRS duration is variable during childhood and can be <80 milliseconds in the neonatal period to <120 milliseconds in adolescents) as observed on electrocardiography. 2 The presentation of SVT can vary based on the age of the patient. Signs and symptoms in infants include poor feeding, vomiting, irritability, increased sleepiness, fainting, and perspiration, as well as pallor, cough, and respiratory distress if congestive heart failure is present. 3 Toddlers and school-aged children will present with palpitations, chest pain, dizziness, shortness of breath, or fainting. Adolescents frequently present with all of these symptoms and may also have perspiration, fatigue, and anxiety. 3 Supraventricular tachycardia is considered an emergency when the patient is hemodynamically unstable, requiring immediate intervention. These patients present with low systolic blood pressure for their age, acute altered mental status, signs of shock, chest pain, or acute severe heart failure symptoms, and they will typically require immediate cardioversion. 4 Patients with SVT who are hemodynamically stable experience an excessively fast heart rate that needs to be addressed, as it can cause uncomfortable symptoms, lead to hemodynamic decompensation, and can recur without intervention. Various interventions can be used to restore normal heart rhythm including vagal maneuvers, pharmacologic intervention, and, in some cases, electrical cardioversion. 4