Right bundle branch block
![](/Images/godic/202501/21/Right_bundle_branch_block_ECG_characteristics3838.png")
![Normal electrical conduction system of the heart (Schematic). All myocardial segments are excited almost simultaneously (purple staining).1. Sinoatrial node2. Atrioventricular node.Conduction in RBBB (Schematic): With a blockage in the right bundle branch (red), the left ventricle is excited in time (purple), while the excitation of the right ventricle takes a detour via the left bundle branch (blue arrows).](/Images/godic/202501/21/Reizleitungssystem_123838.png")
![](/Images/godic/202501/21/Reizleitungssystem_RSB3838.png")
A right bundle branch block (RBBB) is a heart block in the electrical conduction system.
During a right bundle branch block, the right ventricle is not directly activated by impulses travelling through the right bundle branch. The left ventricle however, is still normally activated by the left bundle branch. These impulses are then able to travel through the myocardium of the left ventricle to the right ventricle and depolarize the right ventricle this way. As conduction through the myocardium is slower than conduction through the Bundle of His-Purkinje fibres, the QRS complex is seen to be widened. The QRS complex often shows an extra deflection which reflects the rapid depolarisation of the left ventricle followed by the slower depolarisation of the right ventricle.