Is adenosine recommended as a first-line treatment for ventricular tachycardia in infants or children?

Adenosine is NOT Recommended for Ventricular Tachycardia in Infants or Children

Adenosine should not be used as first-line treatment for ventricular tachycardia (VT) in pediatric patients. Synchronized electrical cardioversion is the preferred initial therapy for unstable VT, while amiodarone may be considered for stable VT with careful hemodynamic monitoring. 1

Why Adenosine is Inappropriate for VT

Mechanism and Indication Mismatch

• Adenosine works by slowing conduction through the atrioventricular (AV) node, making it effective only for arrhythmias that use the AV node as part of their reentrant circuit 2
• Ventricular tachycardia originates in the ventricles and does not involve the AV node in its mechanism, rendering adenosine ineffective 1
• In research studies, adenosine successfully terminated only 1 of 3 ventricular tachycardia episodes (33%), compared to 96% success for supraventricular tachycardias using the AV node 3

Potential Harm

• Critical warning: Adenosine can accelerate ventricular tachycardia, making it potentially life-threatening 3
• Administering adenosine for wide-complex tachycardia of ventricular origin can worsen the clinical situation 2
• The diagnostic use of adenosine in wide-complex tachycardia carries significant risk if the rhythm is actually VT 1

Recommended Treatment for Pediatric VT

For Unstable VT (Hypotension, Poor Perfusion, Altered Mental Status)

• Synchronized electrical cardioversion is the preferred first therapy, starting at 0.5-1 J/kg and increasing to 2 J/kg if needed 1, 4
• This should be performed immediately without delay for pharmacologic interventions 1

For Stable VT

• Amiodarone (5 mg/kg over 20-60 minutes) may be reasonable, though 71% of children experience cardiovascular side effects that are dose-related 1
• Careful hemodynamic monitoring is mandatory during amiodarone administration 1
• Consultation with a pediatric arrhythmia expert is strongly recommended before treating hemodynamically stable children, as all arrhythmia therapies carry potential for serious adverse effects 1, 4

Critical Diagnostic Distinction

Wide-Complex Tachycardia Evaluation

• Wide-complex tachycardia (QRS >0.09 seconds) often originates in the ventricles but may be supraventricular with aberrant conduction 1
• A 12-lead ECG is essential to differentiate VT from SVT with aberrancy before any treatment 4
• Never assume wide-complex tachycardia is supraventricular in origin—treat as VT until proven otherwise 1, 5

When Adenosine IS Appropriate

• Adenosine is the drug of choice (Class I recommendation) specifically for supraventricular tachycardia with narrow QRS complexes (<0.09 seconds) 1, 6
• Dosing for SVT: 0.1 mg/kg rapid IV bolus (maximum 6 mg first dose), followed by 0.2 mg/kg if needed, up to maximum 0.3 mg/kg 6, 2
• Success rates for SVT are 72-96% when the AV node is part of the tachycardia circuit 6, 3

Common Pitfall to Avoid

The most dangerous error is administering adenosine to a child with wide-complex tachycardia without first confirming it is supraventricular in origin. This can accelerate VT or unmask rapid ventricular response in conditions like Wolff-Parkinson-White syndrome with atrial fibrillation 7. When in doubt with wide-complex tachycardia, treat as VT with cardioversion rather than risk adenosine administration 1.