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A 70 yo male presents to the emergency department following a collapse at home. There is no prodrome and he does not remember the incident.
​His ECG is shown below. What is the diagnosis?

There is also a prolonged QTc of about 500. 
There is also a:

  • First degree block
  • RBBB
  • LAFB

I would call this a Trifascicular Block.
Cardiology argued that it was not. Read on to see why they were wrong.

What are the 3 Fascicles?

As the HIS Purkinje system enters the ventricular part of the heart it is composed of the:

  1. Right Bundle: which forms one fascicle
  2. Left Bundle, which is split into:
    1. Anterior and
    2. Posterior fascicles

…Thus 3 fascicles.

If you want to find out about UNI/BI/TRIFASCICULAR Blocks as well as Complete and Incomplete Trifascicular Blocks become a Cardiac Bootcamp Course Member and become the expert.
Cardiac Bootcamp Course Members, go to the Fascicular Blocks page for more.

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