Normally an electrical impulse is generated with the sinus node (normal pacemaker) in the right atrium and the EKG indicates your sinus rhythm is normal. The impulse transmission is normally down a pathway of the wall (septum) that separates the left and right side of the heart termed right bundle branch for the pathways to right side and the left bundle branch for the left side..
Right bundle branch block occurs when transmission of the electrical impulse is delayed or not conducted along the right bundle branch. As a result the right ventricle depolarizes (contracts) by means of cell-to-cell conduction that spreads from the interventricular septum and left ventricle to the right ventricle delaying contraction. It is relatively common where electrical signals reach different parts of your heart muscle at slightly different times. Both left and right ventricles usually contract at the same time, but there is a fraction of a second difference with a RBBB, but of no medical significance.
Hope this helps and thanks for sharing. If you have any further questions or comments you are welcome to respond. Take care,
Ken
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