Bifascicular Block
April 24th, 2019
Overview
Bifascicular block occurs when there is failure of conduction down the right bundle branch as well as either the left anterior or left posterior fascicle.
Look For
- Right bundle branch block - wide QRS (>120ms), RSR' pattern in V1 or V2, slurred S wave in I, V5, V6
- Either left (LAFB) or right (LPFB) axis deviation
- Right bundle branch block:
![Right bundle branch block]()
- Left anterior fascicular block:
![Left anterior fascicular block]()
- Left posterior fascicular block:
![Left posterior fascicular block]()
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