If the patient is asymptomatic in tachycardia, what is the first step to attempt according to the ACLS protocol?

• A. Adenosine
• B. Synchronized cardioversion
• C. Vagal maneuvers
• D. Amiodarone

Answer: (C)

Vagal maneuvers are the first step for a stable, asymptomatic tachycardia because they are a quick, noninvasive way to slow AV nodal conduction and potentially terminate AV nodal reentrant tachycardia without medications or shocks. By increasing parasympathetic tone, these maneuvers can convert the rhythm if it’s AV node–dependent, and they introduce minimal risk. If vagal maneuvers do not restore rhythm, you would move on to pharmacologic options like adenosine for narrow-complex SVT or, if the patient becomes unstable or presents with a wide-complex tachycardia, to synchronized cardioversion as appropriate.