Brief Introduction

The therapeutic principle of atrial fibrillation is to restore and maintain normal sinus rhythm and control the ventricular rate, thereby reducing the risk of stroke.  Currently, atrial fibrillation cardioversion methods include: drug recovery, electrical conversion, interventional radiofrequency ablation, and surgical Maze procedure.  So far, the surgical Maze procedure is the most effective way to treat atrial fibrillation and restore normal sinus rhythm with the highest AF freedom rate.  The Cox-Maze Procedure is a surgical procedure designed to treat atrial fibrillation; it was first applied by Dr. James L. Cox in 1987 [1].  At first, the classic maze procedure was performed by open heart surgery through a sternotomy.  The original method is using surgical technique “cut and sew” to block ectopic pacing lesions.  It is recognized as the “gold standard” to cure AF, given its’ excellent effectiveness (overall freedom from AF rate is 99%) [2].

Even though the success rate is very high, “cut and sew” procedure requires high surgical techniques and longer aortic crossclamp time.  The operation is more invasive with more complications.  Thus, it has not been widely used.  Maze I procedure surgery then was modified twice.  Ralph J. Damiano, Professor James L. Cox's student, with his team at the University of Washington established maze III procedure.  The freedom from AF rate of Maze-III at 10-year was as high as 95% [2].  Dr. Damiano and his team is continuously improving maze procedure.  By improving maze route, maze route creation method and minimally invasive surgery, it became to the latest Maze IV procedure.  A series of incisions of the right atrium were simplified into 2 incisions, and the left atrial incisions were simplified into 1 incision, as well as excision of the left atrial appendage.  After 14 years of follow-up, the freedom from AF rates were as high as 93% [3]. 

The Maze IV procedure utilizes new energy sources (radiofrequency ablation and cryoablation) combined with minimally invasive surgical technique, for significantly reduced aortic cross-clamp time and complications such as postoperative bleeding and conduction block. Currently, it was recognized as the best way to restore normal sinus rhythm for AF patients, and it became the gold standard for surgical treatment of atrial fibrillation [4] [5].  The procedure can be performed during valve replacement or coronary artery grafting.  For AF patients without structural heart diseases, it can be performed under thoracoscopy.  The freedom for AF rate is as high as 90%, which is incomparable to other treatments.  It also has advantages such as high safety and low relative procedural cost.

Learn more about…

References:

【1】Cox JL, et al. The surgical treatment of atrial fibrillation. III. Development of a definitive surgical procedure. J Thoracic Cardiovasc Surg. 1991 Apr; 101 (4): 569 - 83.

【2】Cox JL, et al. Current status of the Maze procedure for the treatment of atrial fibrillation. Semin Thorac Cardiovasc Surg. 2000 Jan; 12 (1): 15 - 9.

【3】Gaynor SL, et al. A prospective, single-center clinical trial of a modified Cox maze procedure with bipolar radiofrequency ablation.  J Thoracic Cardiovasc Surg. 2004 Oct; 128 (4): 535 - 42.

【4】Saltman AE, et al. Surgical approaches for atrial fibrillation.  Cardiol Clin. 2009; 27(1): 179 - 88.

【5】Montecalvo A , et al. Managing the Left Atrial Appendage in the Era of Minimally Invasive Surgery. Interv Cardiol Clin. 2014 Apr; 3 (2): 229 - 238.