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Bundle Branch Block

Information on Bundle Branch Block


Bundle branches within the heart carry electrical impulses through the left and right ventricles at the same time. This causes both ventricles to contract at the same time. Bundle branch block occurs when there is a block in one of the branches. As a result, the electrical impulses are slowed or blocked. This can affect the heart's rhythm.


A heart attack can damage the heart muscle, which can cause bundle branch block.


There are often no symptoms. In some cases, people either faint, or feel faint.


An electrocardiogram (ECG or EKG) can diagnose bundle branch block.


Bundle branch block can cause a slow heartbeat. In these cases, an artificial pacemaker is implanted.