In pediatric patients with stable SVT, what is the preferred initial management?

• A. Adenosine only, no maneuvers
• B. Immediate synchronized cardioversion
• C. Beta-blocker infusion
• D. Vagal maneuvers; if unsuccessful, adenosine

Answer: (D)

The key idea is to use the least invasive method first to restore a normal rhythm in a stable child with SVT. Start with vagal maneuvers to slow conduction through the AV node and potentially interrupt the reentrant circuit. These maneuvers are safe, quick, and can terminate the tachycardia without drugs—examples include age-appropriate Valsalva or similar techniques and diving/ice-water immersion. If these maneuvers fail to terminate the tachycardia, administer adenosine promptly because it momentarily blocks AV nodal conduction and often terminates the SVT with a very short half-life, making it ideal in the acute setting. Synchronized cardioversion is reserved for patients who are unstable or who do not respond to vagal maneuvers and adenosine. Beta-blocker infusions are not the first-line choice for an acute, stable SVT in children.