Narrow Complex Tachycardias: the importance of careful ECG interpretation after cardioversion for tachyarrhythmia

ECG Weekly Workout with Dr. Amal Mattu


A 15-year-old girl presents is brought to the ED complaining of palpitations and near-syncope. She is found to be tachycardic on arrival and the following ECG is obtained:

Before watching this week’s video, ask yourself these questions:

    1. What is the most likely underlying rhythm on the initial ECG?
    2. What is the full ECG interpretation of the repeat ECG after treatment?
    3. What is the most likely cause of her palpitations?