Maze procedure


Maze is a surgical procedure used to treat atrial fibrillation. A doctor creates a pattern of scar tissue (the maze) in the upper chambers of the heart by applying heat or cold. Or, the doctor uses a scalpel to make several precise incisions. This method is more complex and takes longer.

Because scar tissue doesn't carry electricity, the maze interferes with stray electrical impulses that cause atrial fibrillation.

Why it's done

The maze procedure is done to correct atrial fibrillation and improve the quality of life of people with this condition.

The maze procedure is the preferred method of atrial fibrillation treatment if you also need another heart surgery, such as for coronary artery bypass or valve repair. In these cases, the maze procedure is done during open-heart surgery. It may also be the preferred treatment for people who don't respond to other treatments or are experiencing a recurrence of atrial fibrillation.

What you can expect

To be considered for the surgical maze procedure, your heart doctor will have you undergo several tests. If you are scheduled for surgery, your care team will talk with you about how to prepare and what to bring to the hospital.

During the procedure

For the surgical maze procedure, you will be put to sleep with general anesthesia and placed on a heart-lung bypass machine.

Then, your doctor will make an incision in your chest and access the upper chambers of your heart. He or she will use energy — such as heat, cold or laser — or a scalpel to create the pattern of lines. Scar tissue forms where the lines are created. This disrupts faulty electrical signals.

While you are on the bypass machine, your doctor may also do other needed cardiac surgeries, such as valve repair or pacemaker placement.

Some patients may be treated with a robot-assisted catheter ablation procedure called a mini-maze.


Surgical maze procedures have a high success rate, with from 70% to 95% of people being free of atrial fibrillation long term after the procedure. Some people may still need medications to help control their irregular heart rhythm after the procedure. If your atrial fibrillation returns, you may need another catheter ablation or other treatment.

If you develop a slow heart rhythm after your maze procedure, your doctor may suggest you have a pacemaker implanted.

Content Last Updated: February 5, 2020

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