1. Health

Your suggestion is on its way!

An email with a link to:


was emailed to:

Thanks for sharing About.com with others!

Most Emailed Articles

Low-Carb Snacks

Frequently Asked Questions

How dangerous is my bundle branch block – and what can be done about it?

The right and left bundle branches are parts of the heart’s electrical system. On occasion, one of the bundle branches becomes damaged or diseased, and stops conducting the heart’s electrical impulses. When this happens, distinctive changes are produced on the electrocardiogram (ECG), allowing the doctor to diagnose either right bundle branch block (RBBB) or left bundle branch block (LBBB).

In most instances, bundle branch block does is not a serious medical problem, and most of the time does not require implantation of a pacemaker. However, the appearance of bundle branch block (LBBB more so than RBBB) may be an important sign that underlying heart disease is present, and ought to trigger a search for undiagnosed heart disease.

In many individuals, evidence of partial bundle branch block is present on the ECG. (Partial bundle branch block takes two forms – incomplete bundle branch block and the hemiblocks.) As is the case with complete bundle branch block, the partial blocks are generally benign, but may indicate the presence of underlying heart disease.

Despite the generally benign nature of bundle branch block, there are a few circumstances in which bundle branch block may require the implantation of a pacemaker. Click here for a detailed discussion of bundle branch block.

Return to Frequently Asked Questions

What do you think? Enter the Heart Disease Forum:

©2016 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.