Maze Procedure for Atrial Fibrillation

What is a maze procedure for atrial fibrillation?

Maze is a surgical procedure commonly used to treat atrial fibrillation. It is so named because it describes the intricately detailed maze of scar tissue that forms as a result of this corrective surgery.

Atrial fibrillation, or AFib for short, refers to an abnormal electrical activity that occurs in the upper portion of the heart (atria) which causes an irregular heartbeat, also known as heart arrhythmias.

Atrial fibrillation is a dangerous medical condition that can double the risk of death or increase the risk of stroke by 5 – 7 times in patients with the condition, as compared to patients without atrial fibrillation.

How it works

During a maze procedure, your surgeon uses small incisions, radio waves, freezing, microwave or ultrasound energy to create scar tissue.

Because the scar tissue does not conduct electrical activity, it blocks or interferes with the abnormal electrical signals causing the arrhythmia. Instead, the scar tissue directs electric signals through a controlled path, or maze, to the lower heart chambers (ventricles).

Surgical maze procedures have a high success rate. It is estimated that 70% – 95% of people with AFib who underwent the procedure remain free of the condition for the long term after surgery.

Types of maze procedures

There are essentially 2 types of maze procedures:

Minimally invasive surgical ablation (Mini-maze) Open-chest maze surgery
Minimally invasive Invasive
For patients with isolated atrial fibrillation For AFib patients who require heart surgery for other reasons, such as a coronary artery bypass or valve repair
Access is through keyhole incisions on your right side, underneath your armpit Access is through a large incision in your sternum — the bony area that connects the right and left sides of your ribs
A thin catheter is inserted into your heart and heat (radiofrequency) or cold energy (cryoablation) is used to create the lines of scar tissue that block the abnormal electrical impulses In a traditional maze procedure, a scalpel is used to make several cuts in a maze-like pattern in your heart's right and left atria to create the scar tissue that acts as a barrier to keep the electrical signals on their new path
Usually takes 3 – 4 hours to complete Can take up to 6 hours to complete

Why do you need a maze procedure for atrial fibrillation?

Your surgeon may recommend the maze procedure to surgically treat your atrial fibrillation if:

  • Medication has not worked to relieve your symptoms
  • You are having heart surgery to treat other heart conditions
  • You cannot have catheter ablation
  • You have already had catheter ablation, but it did not successfully treat your atrial fibrillation

Who should not undergo a maze procedure for atrial fibrillation?

Not everyone with AFib is a suitable candidate for atrial fibrillation surgery. To determine if surgical treatment is appropriate, your surgeon or doctor will need to perform a thorough evaluation, which includes:

After the evaluation, your surgeon will discuss your treatment options with you and to determine if you are a candidate for surgery.

What are the risks and complications of a maze procedure for atrial fibrillation?

While any medical procedure carries risks, complications from minimally invasive ablation surgeries are low.

Side effects include:

  • Bleeding
  • Bruising
  • Mild pain
  • Damage to blood vessels

More serious complications include stroke or abnormal fluid collection around your heart, but these complications are rare.

The open-heart maze procedure involves greater risks than ablation because it involves open-heart surgery. Risks include:

  • Kidney failure
  • Other organ failure
  • Stroke
  • Death

You may also require a pacemaker after undergoing the maze procedure.

While it poses risks of serious complications, the maze procedure also has a high success rate.

This page has been reviewed by our medical content reviewers.

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