Medically reviewed on March 16, 2018
The surgical maze procedure is treatment for atrial fibrillation in which your doctor creates a pattern of scar tissue (the maze) in your heart. He or she etches the tiny lines by applying heat (radiofrequency energy) or cold (cryoablation) to the upper chambers of your heart. Or he or she may use a scalpel to make several precise incisions. This method is more complex and takes longer.
Because scar tissue doesn't carry electricity, it interferes with stray electrical impulses that cause atrial fibrillation.
Why it's done
Maze surgery is done to correct atrial fibrillation and improve the quality of life of people with this condition.
Maze surgery 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 (cardiologist) 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
You will be put to sleep with general anesthesia and placed on a heart-lung bypass machine.
For a surgical maze procedure, your doctor will make an incision in your chest and access the upper chambers of your heart. He or she will use one of several techniques to create the pattern of lines (maze). This leaves scar tissue that disrupts faulty electrical signals. Your doctor may create the lines with energy — such as heat, cold (cryotherapy) or laser — or with a scalpel.
While you are on the bypass machine, your doctor may also do other needed cardiac surgeries, such as valve repair pacemaker placement. In one study of 75 patients, 40 percent had pacemakers implanted during their maze surgery to help normalize their heart rhythm after surgery.
Select 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 percent of people being free of atrial fibrillation long term after the procedure. Up to 35 percent may still need medications to help control their irregular heart rhythm. If your atrial fibrillation recurs, 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.