An organization of nerve fibers along the heart’s ventricular septum that conveys electrical impulses to the ventricles to cause them to contract, also called the bundle of his.
The right bundle branch extends to the right ventricle and the left bundle branch to the left ventricle. The electrical impulses, which originate with the sinoatrial (sa) node, intensify as they travel along the bundle branches.
The bundle branches, as the name implies, branch out into smaller and smaller fibers culminating in the Purkinje fibers, which disperse the electrical impulses to the myocardial cells throughout the ventricles.
For further discussion of cardiovascular structure and function, please see the overview section “The Cardiovascular System.”