Management of neonatal supraventricular tachycardias; A single center experience

Abstract

The incidence of neonatal arrhythmias is reported as 1-5%. [1, 3, 4] Neonatal arrhythmias are classified as benign and nonbenign arrhythmias and have various clinical manifestations. Supraventricular tachycardia (SVT), ventricular tachycardia (VT), atrioventricular conduction disorders and genetic disorders such as long QT syndrome are classified as non-benign arrhythmias. [1, 4, 5] Supraventricular tachycardia is the most common non-benign tachycardia among neonates, and reentry tachycardia via accessory pathway is the most common SVT in neonates and infants. [6, 7] Clinical manifestations of the tachycardia mainly depends on the heart rate and urgent diagnosis and accurate treatment is very crucial because the tachycardia may lead to life threating conditions such as hypotension, heart failure and shock. [8] A regular heart rate of >220/beats per minute, absent or altered axis P waves, and a QRS complex with a duration of <0.08 ms (unless aberrant conduction is present) are the typical ECG findings of supraventricular tachycardia. [9] Treatment of SVT is classified into three: 1) Abortive treatment, 2) Acute treatment 3) Secondary prevention or prophylactic treatment to prevent recurrence. [10, 11] The aim of this study is to evaluate the newborns diagnosed with supraventricular tachycardia in means of diagnosis, treatment, and follow-up. Objectives: Emergent treatment of neonatal supraventricular tachycardia (SVT) is very crucial because it may lead to life threating conditions. The aim of this study is to evaluate the neonatal SVTs. Methods: Neonates, who were diagnosed with SVT between December 2014 and May 2018, were analyzed. Clinical findings, electrocardiogram (ECG) and echocardiography findings, 24-hour Holter ECG recordings and medications were evaluated. Results: 46 over 1932 newborns were diagnosed with SVT. 76% of patients were common SVT with narrow QRS and short RP, 13% with Wolff-Parkinson-White syndrome, 4.3% with multifocal atrial tachycardia, 4.3% with atrial flutter, 2.1% with permanent reciprocating junctional tachycardia. Adenosine terminated SVT in 84.4% of the cases. Synchronized cardioversion was performed in 10.8% cases. Amiodarone and/or esmolol for acute treatment was used in 39.1%. Propranolol, digoxin, amiodarone, propafenone and flecainide were the drugs used for monotherapy or combination therapies. Conclusion: In patients with initially unresponsive to standard dose of adenosine and under acute treatment with amiodarone and/or emolol continuous infusion, higher doses of adenosine (300-500 µg/gr/kg) is very effective. Amiodarone alone and in combination with flecainide seems safe and effective.

Amiodarone and Adenosine for Pediatric Supraventricular Tachycardia: A Systematic Review

“…In a lot of situations, there is a chance that SVT will resolve spontaneously in infants because of the nature of their arrhythmia patterns. This gives us optimism, for managing it without measures [4,11,12].…”