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Can it be RBBB+LBBB in the same tracing?
- Thread starter David123
- Start date
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Unless I'm mistaken having both a LBBB and RBBB is a complete heart block or 3rd degree block. With both branches blocked the conduction "super highway" between the atria and ventricles is completely blocked thus causing a CHB.
Now you can have fascicles of both bundle branches blocked and not have a complete heart block. Example being a RBBB + LAFB or LPFB (left anterior fascicular block - more common or left posterior fascicular block - less common). A RBBB+LAFB (or LPFB) is commonly known as a bifasicular block. A trifascicular block would be a 1st degree AVB+RBBB+LAFB (or LPFB).
You cannot have a bifascicular block with a LBBB unless it's a LBBB alternating with a RBBB which is rare because the Right Bundle Branch only has one fascicle whereas the Left Bundle Branch has two fascicles being the anterior and posterio fascicles.
Clear as mud?
I'm sure the link provided by @Aprz explains it better than I did as he is an ECG/cardiology/electrophysiology guru.
Now you can have fascicles of both bundle branches blocked and not have a complete heart block. Example being a RBBB + LAFB or LPFB (left anterior fascicular block - more common or left posterior fascicular block - less common). A RBBB+LAFB (or LPFB) is commonly known as a bifasicular block. A trifascicular block would be a 1st degree AVB+RBBB+LAFB (or LPFB).
You cannot have a bifascicular block with a LBBB unless it's a LBBB alternating with a RBBB which is rare because the Right Bundle Branch only has one fascicle whereas the Left Bundle Branch has two fascicles being the anterior and posterio fascicles.
Clear as mud?
I'm sure the link provided by @Aprz explains it better than I did as he is an ECG/cardiology/electrophysiology guru.
@Handsome Robb I literally linked him to page from Dubin Dale's Rapid Interpretation of EKGs. I initially wrote a really really long novel, but deleted it to keep it simple. I felt the picture from the book with the short explanation would answer his question without confusion.