Such blocks sometimes are due to underlying cardiac disease.
Abnormal heart rhythm because of bundle branch block can be diagnosed with anelectrocardiogram (ECG)orechocardiogram.
Thesinus nodeis a bundle of nerves located in the right atrium.
Verywell / Gary Ferster
When the bundle branches are functioning normally, the right and left ventricles contract regularly and nearly simultaneously.
This is described asnormal sinus rhythm.
This leads to a disruption of heart rhythm as it pumps.
A left bundle branch block interferes with the contraction of the left ventricle.
The contraction of the right ventricle is normally slightly less powerful than the contraction of the left ventricle.
A right bundle branch block disrupts the contraction of the right ventricle.
However, it can cause intermittent effects, including dizziness and even syncope (fainting).
However, bundle branch block may be resulting from underlying heart disease.
In fact, left bundle branch block is almost always associated with a cardiac condition of some key in.
An echocardiogram is a non-invasive ultrasound that visualizes the heart as it beats, potentially detecting disruptions in rhythm.
In the figure above,Panel Ashows what a normal QRS complex looks like on a normal ECG.
In this case, the bundle branch block is referred to as an intraventricular conduction delay.
Echocardiogram
A bundle branch block might be detected with an echocardiogram.
This non-invasive test allows healthcare providers to visualize the motion and rhythm of the heart as it beats.
More importantly, this test gives healthcare providers a detailed view of the heart.
A Word From Verywell
Bundle branch block is not an uncommon incidental finding on an ECG.
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