Maze Procedure (Minimally Invasive)

Contact Information

(608) 263-0439


Related Conditions

Atrial Fibrillation

Heart Disease (Coronary Artery Disease)


Internet Resources

American Heart Association

UW Health cardiothoracic surgeons in Madison, Wisconsin, perform a minimally invasive Maze procedure for atrial fibrillation that cannot be treated with medication or other non-surgical procedures.


This procedure, also known as "mini maze," allows the surgeon to correct the electrical irregularity in the atria without performing open-heart surgery. With the minimally invasive Maze procedure, patients experience fewer potential complications and a much shorter hospital stay than with traditional open surgery.


Our doctors have been performing minimally invasive atrial fibrillation surgery for several years, and we have been offering this procedure at UW Hospital and Clinics since February 2005.


Maze ProcedureThe Procedure


When you undergo minimally invasive Maze surgery at UW Health in Madison, Wisconsin, the procedure takes two to three hours. You will be under general anesthesia during surgery.


First, an anesthesiologist inserts a breathing tube into your trachea (the airway from your mouth to your lungs). Through this tube, the right lung is deflated. This allows you to to breathe through the left lung, with ventilator assistance, while the surgeon accesses your heart. This way, the heart-lung bypass machine is not needed during surgery.

Maze Procedure 

The surgeon then makes three small incisions on the right side of the chest (see Figure 1).


The surgeon then inserts a video camera and small instruments through the incisions. The surgeon opens the sac around the heart (the pericardium) and inserts two catheters around the heart (see Figure 2). Once these catheters are in place, the right lung is reinflated.

 Maze Procedure

The surgeon then makes three incisions on the left side of the chest, deflates the left lung, and inserts the camera and instruments.


The surgeon opens the pericardium from the left side, retrieves the catheters, pulls them around the heart, and connects them at the left side. This forms a loop around the heart. (see Figure 3)


Using the catheter loop as a guide, the surgeon then advances a microwave probe around the left atrium, at the base of the left and right pulmonary veins. When the probe is Maze Procedureactivated, the heat generated from it creates a lesion around the atrium. This is called ablation. (see Figure 4)


The scar tissue that forms after the ablation prevents the abnormal electrical impulses from affecting the rest of the heart. After ablation, the surgeon reinflates the left lung, removes the instruments and camera, and closes and bandages all incisions.