Can You Explain the MAZE Procedure?

A MAZE procedure also commonly called a COX Maze procedure is designed to surgically correct atrial fibrillation. Most often it is performed as a “concomitant” procedure with another operation as primary. In other words the MAZE is performed at the same time as another open heart operation. During a MAZE procedure, your surgeon will make a series of “lesions” or scars in the upper chambers of the heart in an effort to block the spread of the electrical stimulus which leads to atrial fibrillation. There are numerous energy sources such as radiofrequency or “RF”, ultrasound and “cryo” or freezing.

When performed as an adjunct or concomitant procedure it adds little risk to the procedure and requires no additional incisions. Success rates vary depending on the patient populations but success rates of 80 percent or greater have been reported.

Isolated or stand alone MAZE procedures are also performed. In this instance the MAZE procedure with excision of the left atrial appendage constitutes the whole operation. Typically this procedure is the last resort for patients with “isolated atrial fibrillation”. These patients have not been successfully treated by other commonly used methods and typically have had one or more ablations, done by the electrophysiologists with a catheter. These stand alone MAZE procedures, are most often performed utilizing minimally invasive techniques which avoids a sternotomy (opening of the breast bone).

The minimally invasive procedure can usually be done through 2-3 small incisions between the rib on either the right side or in some instances incisions on both sides of the chest.