right bundle branch block

Dear Doctors,
My two brothers recently had ECGs done for long QT screening.  Both ECGs read them as having RBBB.  They are both smokers and in their 40's.  We do have young deaths (20's and 30's) due to cardiac problems-  blocked arteries.  Many of the men in our family had heart attacks in their 30's and 40's also.  Should my brothers be concerned with the RBBB?  What is a RBBB?  Is there treatment for it?  Should they go through further testing?
Thank you again for your time!
Laurie

[Cleveland Clinic, MD]

Dear Laurie,
Right bundle branch block (RBBB) is due to a conduction block in the right bundle of the heart's electrical system.  There may be some increased cardiac risk for individuals with this underlying condition.  Your brothers may wish to talk to their doctors about getting a screening exercise test.  In addition they really need to quit smoking.