The maze procedure is the primary form of treatment for resolving atrial fibrillation (Afib). If the condition is not severe, doctors may suggest alternative solutions, such as anticoagulants, electrical cardioversion, and medications. When medications are prescribed, the goal may be twofold. Your doctor might seek to reduce the rate of your ventricles' beating and control your heart's rhythm. It's important to underscore that none of these approaches cure Afib; they merely represent strategies to treat the symptoms.
The underlying cause of atrial fibrillation is erratic electrical signals that spread rapidly through your atria in a disorganized pattern. Below, you'll learn about the different types of maze surgery that are performed to cure the disorder. The procedure has evolved over the last 25 years and now involves minimally invasive techniques.
Cox Maze III
The original method (called the Cox Maze) was developed by Dr. James Cox in 1987. It involved the surgeon making a series of incisions into the patient's atria to create a maze through which the erratic electrical signals could be guided. This occurred as the result of scar tissue, which cannot conduct an electrical current.
Since 1987, Dr. Cox's method has evolved. The Cox Maze III is one of a series of iterations and still uses incisions to create scarring. Because the procedure is complicated, many surgeons have abandoned it for other methods that yield the same results with a lower mortality rate. One of those methods is called the Cox Maze IV.
Cox Maze IV (Surgical Ablation)
This iteration of Dr. Cox's original procedure uses surgical ablation to create scar tissue rather than incisions. The ablative energy can come from a number of different sources, including microwave, cryoablation, bipolar radiofrequency, laser, and ultrasound. It is just as effective as the previous version, but can be performed in less time with fewer complications.
The Cox IV is typically performed when the patient is already undergoing other open-heart procedures (i.e. coronary artery bypass graft, mitral valve repair, etc.) It can be done while the patient's heart is arrested or while it is still beating. While the Cox IV can be used to cure atrial fibrillation, most Afib cases that are standalone are resolved through the minimaze strategy.
Minimaze
The minimaze method is a minimally invasive procedure for curing atrial fibrillation when the patient does not need other types of heart surgery. If the patient is only suffering from Afib, there's no need to perform open heart surgery or arrest his or her heart. The minimaze can be performed with a few small incisions.
The entire operation takes a few hours. The surgeon will make three or four incisions on each side of the patient's chest. The ablation tool, thoracoscope, and other instruments are inserted through these incisions to access the heart.
Catheter Ablation
Catheter ablation is similar to the minimaze, though the route taken to the heart is slightly different. It too, is a minimally invasive strategy. A catheter is inserted into the groin, arm, or neck, and guided toward the heart. A small hole is made in the septal wall to allow the catheter to pass from the right atrium to the left atrium. There, it ablates the tissue to create a conduction block. As with other forms of maze surgery, the conduction block prevents the passage of erratic electrical signals.
Maze surgery has evolved substantially since Dr. Cox developed his original method in 1987. The tools available to surgeons have likewise evolved. From the Cox III and IV to the minimaze and catheter ablation, new methods are currently in development. The takeaway is that atrial fibrillation can now be cured without the need to undergo open heart surgery. For many patients, that opens the door to finally resolving a longstanding heart condition.