Right Bundle Branch Block is a delay or block of conduction within the right bundle branch. In complete RBBB, the duration of QRS is >120ms and in incomplete RBBB it is between 100 and 120ms.
The ECG Criteria is as follows:-
- QRS duration >120ms
- rsR pattern in lead V1 with R’ >r
- Slurred S wave in lead I
Clinical Implications of Complete RBBB
- RBBB can be seen as a normal finding in the absence of heart disease.
- It may be associated with CAD, cardiomyopathies, Ebstein’s anomaly, Atrial Septal Defect and persistent atrioventricularis communis.
- In the presence of heart disease, prognosis is related to the severity of the underlying heart disease.
- RBBB complicating acute MI has poor prognosis.