Bifascicular block is characterized by
right bundle branch block
A right bundle branch block (RBBB) is a heart block in the Bundle branches#Structure, right bundle branch of the Electrical conduction system of the heart, electrical conduction system.
During a right bundle branch block, the right ventricle (h ...
with
left anterior fascicular block, or
right bundle branch block
A right bundle branch block (RBBB) is a heart block in the Bundle branches#Structure, right bundle branch of the Electrical conduction system of the heart, electrical conduction system.
During a right bundle branch block, the right ventricle (h ...
with
left posterior fascicular block on
electrocardiography
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity through repeated cardiac cycles.
It is an electrogram of the heart which is a graph of voltage versus time of t ...
. Complete
heart block could be the cause of
syncope that is otherwise unexplained if bifascicular block is seen on
electrocardiography
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity through repeated cardiac cycles.
It is an electrogram of the heart which is a graph of voltage versus time of t ...
.
It is estimated that less than 50% of patients with bifascicular block have high-degree
atrioventricular block, although the exact incidence is unknown.
The
European Society of Cardiology
The European Society of Cardiology (ESC) is an independent Nonprofit organisation, non-profit, non-governmental professional association that works to advance the prevention, diagnosis and management of diseases of the heart and blood vessels, a ...
(ESC) suggests using
studies to look into it (EPS). When pharmacologic stress or incremental atrial pacing induces high-degree
atrioventricular block, a permanent
pacemaker (PPM) is recommended. If EPS is negative, long-term rhythm monitoring with an
implantable loop recorder (ILR) is advised.
Most commonly, it refers to a combination of
right bundle branch block
A right bundle branch block (RBBB) is a heart block in the Bundle branches#Structure, right bundle branch of the Electrical conduction system of the heart, electrical conduction system.
During a right bundle branch block, the right ventricle (h ...
(RBBB) and either
left anterior fascicular block (LAFB) or
left posterior fascicular block (LPFB), with the former being more common.
Signs and symptoms
Patients who suffer from bifascicular block are more likely to experience
syncope and unexpected death.
Diagnosis
Treatment
In those with bifascicular block and no symptoms, little with respect to treatment is needed. In those with
syncope, a
pacemaker is recommended.
See also
*
Trifascicular block
Trifascicular block is a problem with the electrical conduction of the heart, specifically the three fascicles of the bundle branches that carry electrical signals from the atrioventricular node to the ventricles. The three fascicles are one in t ...
*
Bundle branch block
A bundle branch block is a partial or complete interruption in the flow of electrical impulses in either of the bundle branches of the heart's electrical system.
Anatomy and physiology
The heart's electrical activity begins in the sinoatri ...
References
Further reading
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*
External links
Cleveland ClinicLife in the Fast Lane
{{Circulatory system pathology
Cardiac arrhythmia