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MAZE Procedure for Treatment of
Atrial Fibrillation

The Maze Procedure is surgery performed to treat atrial fibrillation. During the procedure, a number of incisions are made on the left and right atrium to form scar tissue, which does not conduct electricity and disrupts the path of abnormal electrical impulses. The scar tissue also prevents erratic electrical signals from recurring. After the incisions are made, the atrium is sewn together to allow it to hold blood and contract to push blood into the ventricle.

MAZE Procedure using Atricure hand piece

Although the atrium is sewn back together, the erratic electrical paths remain severed so that no unwanted electrical impulse can cross the incision. The result is what looks like a children's maze in which there is only one path that the electrical impulse can take from the SA node to the AV node. The atrium can no longer fibrillate, and sinus rhythm (the normal rhythm of the heart) is restored. Maze can be performed either through an open chest procedure or a minimally invasive procedure. Ninety percent of Maze surgeries are concomitant (done in conjunction) with other open chest surgery, such as coronary artery bypass grafting, mitral valve repair and/or valve replacement.

Open Chest Maze Surgery

Open chest Maze surgery means that the sternum is divided to allow access to the chest. During this surgery, the heart is stopped and a heart-lung machine is used. Scissors are used to open the pericardium to gain access to the heart.


Multiple energies are used during open chest Maze surgery:

Minimally Invasive Maze Surgery (beating heart)

Minimally invasive maze surgery is performed through small keyhole incisions made between the ribs, through which a tiny camera and video guided instruments are inserted. When appropriate, robots are used to assist the surgeon during the procedure.

Go to: Robotic-Assisted MAZE Surgery | Minimally Invasive Cox-Maze | Wolf Mini Maze

This minimally invasive surgery eliminates the need for dividing the breastbone (sternum), does not require the heart to be stopped, and does not require a heart-lung machine to be used. This often results is shorter recovery time and a lower risk of infection associated with open-heart surgery.

Wolf Mini Maze Incisions

As a tiny camera guides the surgeon inside the chest, a catheter directs cryo-freeze or microwave energy to perform the ablation. The energy is aimed at precise areas in the heart tissue, creating lesions that interrupt the paths of abnormal circuits which cause atrial fibrillation.

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MAZE Procedure
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