Management of Bundle Branch Block
Right Bundle Branch Block (RBBB)
The structural heart diseases associated with RBBB are:
- Cor pulmonale
- Pulmonary embolism
- Myocardial ischemia/infarction
- Congenital heart disease
Outcomes depend on comorbidities (underlying heart disease), and those with RBBB without heart disease have excellent long-term outcomes.
If there are no symptoms and there is no underlying heart disease, treatment is limited to just serial observation (close surveillance for ECG follow-up and for symptoms that may occur).
If there are symptoms in the pre-syncope to syncope range, treatment is with an implanted cardiac pacemaker if no reversible causes are identified, e.g., electrolyte disturbances, medications, etc.
Left Bundle Branch Block (LBBB)
If a patient with LBBB is asymptomatic and has no underlying heart disease, no therapy is indicated other than close surveillance with serial ECGs and for the emergence of symptoms.
If a patient is symptomatic (pre-syncope, syncope, and other cognitive changes) and if there are no reversible causes (electrolyte disturbances, medications, etc.), a permanent pacemaker is indicated to treat any symptomatic conduction system disturbances.
Decreases in left ventricular fraction cardiac output may require a selective pace making protocol that involves using cardiac resynchronization therapy. Such pacemakers selectively pace the ventricles or only the left ventricle to reestablish a normal cardiac output.