Hi Mamatha 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 n most people, bundle branch block doesn t cause any symptoms Sometimes, people with the condition don t even know they have a bundle branch block. For those people who do have signs and symptoms, they may include: Fainting (syncope) Feeling as if you re going to faint (presyncope) if the symptoms are severe please see a cardiac surgeon and then a pace maker may be required Wish Your Father Good Health Regards Dr Sridhar K