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Reverse left septal activation during intermittent left bundle-branch block: indirect proof for concealed retrograde
Philippe Maury1, Alexandre Duparc, Aurélien Hébrard
1Federation of Cardiology, University Hospital Rangueil, Toulouse Cedex 09, France. mauryjphil@hotmail.com
Journal of Electrocardiology
|June 13, 2009
Summary
Direct evidence for concealed retrograde activation in bundle branch block is rare. This study presents intracardiac recordings suggesting reversed septal activation during left bundle-branch block, potentially explaining its persistence.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Anatomy
Background:
- Functional rate-dependent bundle-branch block is often explained by concealed retrograde activation.
- Direct proof of this mechanism in humans is seldom documented.
Observation:
- Intracardiac recordings revealed reversed activation of the left basal interventricular septum.
- This observation occurred during intermittent left bundle-branch block.
Findings:
- Retrograde activation into the left bundle branch was not directly recordable.
- This non-recordability is likely due to concealment within the muscular septal activation.
Implications:
- The findings support the linking phenomenon hypothesis for bundle-branch block perpetuation.
- This study provides rare direct evidence for concealed retrograde activation in humans.
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