Your question has been posed by many patients in the past, so Im glad you asked it. The right bundle is an electrical pathway which carries signals to the right ventricle, causing it to contract. There is also a left bundle, which delivers signals to the left ventricle. Think of these bundles as "electrical highways" that bring signals to the heart muscle tissue. If one of the highways is interrupted, then the intended site of delivery needs to get its signals from the other side of the heart, by cell-to-cell communication. The other side of the heart will be stimulated to contract, but a little bit later than it normally would. In the case of RBBB, the slower electrical activation of the right ventricle shows up as a widened complex on your electrocardiogram (EKG).