Atrial fibrillation (also called AF) is an arrhythmia characterized as irregular, disorganized, electrical activity of the upper chambers (atria) of the heart. The atria quiver instead of regularly beating which causes them to move around 300-600 times a minute (instead of 60-80 times a minute). Because the upper chambers are quivering so rapidly, the blood is not allowed to completely empty and causes pooling in the atria.
The Maze Procedure is surgery performed to treat atrial fibriallation. This is sometimes referred to as the Cox Maze procedure. During the procedure, a pattern of scars are formed on the left and right atria to produce a pathway that allows normal conduction of the heart. This can be done in a number of ways, either by cutting and then sewing the atrium back together or by using an energy source to create the scar – either Radiofrequency ablation (RF) or Cryotherapy (cold therapy).
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 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 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.
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.
Once the lesion set is completed the patient is returned to the ICU. A standard length of stay would be between 4 and 7 days in hospital. Post operatively you can expect to be discharged on warfarin and whichever antiarrhythmic medication you were taking prior to the surgery. These will be weaned off at 3 or 6 months. Prolonged follow up includes Holter monitor at 3,6 and 12 months.