The Maze procedure is a surgical operation used to treat chronic atrial fibrillation, typically when medications and catheter ablation have not worked or are unsuitable. During the procedure, a surgeon creates a precise pattern of scar tissue within the atrial muscle using incisions, radiofrequency energy, or cryotherapy. Scar tissue does not conduct electricity, so the resulting “maze” of scars forces electrical impulses to travel along a controlled pathway, restoring coordinated contraction and normal sinus rhythm.
The original Cox-Maze III procedure involved cut-and-sew incisions and was highly effective but technically demanding. Modern variations use energy-based ablation to create the same lesion pattern with less operative time and faster recovery. The Maze procedure is most commonly performed alongside other cardiac surgery, such as valve repair or coronary artery bypass grafting, rather than as a standalone operation.
Success rates for restoring sinus rhythm are high, with studies reporting 70 to 90% freedom from AF at five years in selected patients. However, some individuals still require anticoagulation or rate control medication after surgery, depending on individual risk. As catheter-based ablation techniques have improved, standalone surgical Maze procedures have become less common. Patients being considered for Maze surgery are usually discussed at a multidisciplinary team meeting.
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