STAT ECG Diagnoses: what exactly is Ashman phenomenon and why does it matter?

ECG Weekly Workout with Dr. Amal Mattu


A 50-year-old male with PMHx of atrial fibrillation presents to the ED with palpitations. He is found to be tachycardic, and while being treated for suspected atrial fibrillation with RVR, is found to have intermittent runs of wide complex tachycardias. The following ECG was obtained during an episode:

Before watching the video, look closely at this ECG and ask yourself:

  1. What is the heart rate and underlying rhythm?
  2. What is the most likely cause of the wide QRS beats seen?
  3. How would you manage this rhythm?