What is the Maze procedure?

What is the Maze procedure?

A surgery called the Maze procedure was developed to ablate atrial fibrillation. In the Maze procedure, several incisions or lesions are created in the right and left atria in order to form scar tissue that blocks the chaotic electrical impulses from entering the heart. As a result, the electrical impulses are channeled into a single path to the atrioventricular (AV) node, as normal, to allow the atrium to contract uniformly. The AV node then sends the signal to the ventricles, causing them to contract.

Almost all of these surgical approaches include removal of the left atrial appendage, a small, ear-shaped flap of tissue located in the left atrium. The left atrial appendage is a potential source of blood clots in patients who have atrial fibrillation.

Advantages of the Maze procedure in patients who have atrial fibrillation are reduced risks of stroke, blood clots, and hemorrhage.

The traditional surgical Maze procedure is known as the "cut and sew Maze" because it relies on surgical incisions. It is difficult to perform and requires that the heart be stopped for 45 to 60 minutes, during which time a heart-lung machine is used to circulate blood.

Instead of cutting into the wall of the atria, newer techniques to perform Maze surgery use such techniques as radiofrequency, microwave, laser, ultrasound, or cryoablation (freezing). The Cox-Maze III procedure, for example, is a less invasive Maze procedure that uses a bipolar radiofrequency energy. It takes less time to perform than the traditional "cut and sew" Maze procedure.

In patients with atrial fibrillation who also have certain forms of structural heart disease, a modified Maze procedure using cryoablation lesions in addition to surgical lesions is effective at blocking abnormal electrical impulses from re-entering the heart.