Heart Health

How serious is bundle branch block?

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A recent electrocardiogram showed that I have a right bundle branch block. My doctor says it's fairly common and nothing to worry about, but I'm a bit concerned. What is it, exactly? And what specifically can cause this problem?

The electrical signal is supposed to travel at the same speed through the right and the left bundle branches so that both ventricles contract in sync. But if a signal is blocked in one of these pathways, the ventricle with the block will contract a fraction of second later than the other ventricle. The blockage is generally only on one side, so people have either right bundle branch block or left bundle branch block.

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