Clinical Scenario:
A 3-month-old girl admitted to the Pediatric Intensive Care Unit is a known case of Ebstein anomaly and is being treated for heart failure. During your duty, the nurse reports that the infant has developed marked tachycardia. An ECG confirms supraventricular tachycardia (SVT). The child remains hemodynamically unstable despite ongoing treatment for heart failure.
What is the most appropriate initial management?
A. Carotid massage
B. Intravenous adenosine
C. Rapid verapamil infusion
D. Synchronized DC cardioversion
E. Transthoracic pacing
Correct answer & Explanation:
Answer: D. Synchronized DC cardioversion
Explanation: Supraventricular tachycardia (SVT)
This infant has SVT with hemodynamic instability in the setting of underlying congenital heart disease and heart failure. The treatment of choice for unstable SVT is synchronized DC cardioversion, which should be synchronized with the QRS complex to avoid inducing ventricular fibrillation.
Why not the other options?
- A. Carotid massage: A vagal maneuver that may be attempted in stable patients but is not appropriate in an unstable infant.
- B. Intravenous adenosine: First-line pharmacologic therapy for stable SVT but should not delay cardioversion in an unstable patient.
- C. Rapid verapamil infusion: Contraindicated in infants because it may cause severe hypotension, cardiovascular collapse, and cardiac arrest.
- E. Transthoracic pacing: Primarily used for symptomatic bradyarrhythmias and has no role in the initial management of SVT.
