Bundle branch block

Bundle branch block is a condition in which there's a delay or obstruction along the pathway that electrical impulses travel to make your heart beat. The delay or blockage may occur on the pathway that sends electrical impulses to the left or the right side of your heart.

Bundle branch block sometimes makes it harder for your heart to pump blood efficiently through your circulatory system.

There's no specific treatment for bundle branch block itself. However, any underlying health condition that caused bundle branch block, such as heart disease, will need to be treated. Sometimes, bundle branch block is associated with other problems in the heart's electrical system that can lead to dangerously slow heartbeats that need treatment with a temporary or permanent pacemaker.

Symptoms Causes Complications Prevention

In most people, bundle branch block doesn't cause any symptoms. Sometimes, people with the condition don't even know they have a bundle branch block.

For those people who do have signs and symptoms, they may include:

  • Fainting (syncope)
  • Feeling as if you're going to faint (presyncope)
  • Having a slow heart rate (bradycardia)

When to see a doctor

If you've fainted, see your doctor to rule out any serious, underlying causes.

If you have heart disease, or if your doctor has already diagnosed you as having bundle branch block, ask your doctor how often you should have follow-up visits. You might want to carry a medical alert card that identifies you as having bundle branch block in case you're seen in an emergency by a doctor who isn't familiar with your medical history.

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