The Maze procedure involves sequential atriotomy incisions, which interrupt potential re-entrant circuits, and are used to restore the normal atrial pacemaker complex and allow activation of the entire atrial myocardium to preserve atrial transport function. This document addresses the use of the Maze procedure as a curative surgical treatment of atrial fibrillation or flutter for individuals who do not respond to medical therapies.

Note: For additional information, please see MED.00064 Transcatheter Ablation of Arrhythmogenic Foci in the Pulmonary Veins as a Treatment of Atrial Fibrillation (Radiofrequency and Cryoablation).

Medically Necessary: 

The Maze procedure is considered medically necessary for drug resistant atrial fibrillation or flutter.

The Maze procedure is considered medically necessary for individuals with highly symptomatic atrial fibrillation who require open heart surgery for valvular, ischemic, or congenital heart disease.

Not Medically Necessary:

The Maze procedure is considered not medically necessary for all other indications.

The following codes for treatments and procedures applicable to this document are included below for informational purposes.  Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

Future ICD-10 coding (effective 10/01/2013)

A draft of ICD-10 Coding related to this document, as it might look today, is available for reference and comments at: Appendix 1: Future ICD-10 coding

Atrial fibrillation (AF) is the most common persistent arrhythmia with an increasing prevalence with age. Long-term morbidity includes increased risk for stroke, heart failure and increased morbidity and mortality (Fuster, 2006; Saltman, 2009).  

The Maze procedure is the "gold standard for surgical treatment of atrial fibrillation" (Saltman, 2009; Weimar, 2011) and is the most effective curative surgical treatment of atrial fibrillation or flutter for individuals who do not respond to medical therapies. This open surgical procedure is frequently combined with other cardiac surgeries and involves complex, sequential atriotomy incisions and is performed on a non-beating heart during cardiopulmonary bypass. The incision pattern and the resulting scar tissue do not conduct electrical activity, thus decreasing the signals leading to aberrant atrial fibrillation. Since its development, modifications have been made to the original Maze procedure to improve efficacy and decrease operative time, creating the now standard Cox Maze III procedure. Long-term followup from various studies have reported the efficacy of the Maze procedure may range from 70% to 96% of individuals who establish sinus rhythm after undergoing the Maze procedure (Fuster, 2006; Saltman, 2009).

Kong and colleagues (2010) performed a meta-analysis of randomized trials comparing the efficacy of surgical Maze procedures performed concomitantly with cardiac surgery compared to cardiac surgery alone for the treatment of atrial fibrillation. Nine randomized studies using Cox-Maze III or modified Maze ablation procedures enrolled a total of 472 individuals. Three studies did not report freedom from AF within 12 months and one study enrolled participants with paroxysmal AF. The 5 remaining studies suggest that the "surgical Maze procedure greatly increases the odds of freedom from AF within 12 months postprocedure. The estimated odds ration is 5.22 (95% confidence interval [CI], 1.71 to 15.88)" (Kong, 2010). There was no significant difference in operative mortality rates of 4.0% in the treatment group versus 3.3 % in the control group. There was also no significant difference in the overall rate of major complications with the treatment group experiencing 24.4% and the control group with a complication rate of 24.9%. There was no significant difference in freedom from AF and anti-arrhythmic drugs (AADs) in participants treated with cardiac surgery alone (51.9%) compared to those treated with Maze procedure and a concurrent cardiac surgery (53.3%). The authors cautioned that the studies were heterogenous and the ablative techniques and modifications to the Maze procedures were not standardized. Therefore, large randomized trials with long-term followup are recommended to determine the efficacy of the Maze procedure for maintenance of sinus rhythm (Kong, 2010).

In a controlled study by Cui (2008), 45 individuals with long-standing, persistent AF with mitral valve disease were enrolled for concomitant open-heart surgery and a mini-Maze procedure using radiofrequency ablation. The control group included 40 individuals who were treated with radiofrequency Cox Maze III. All participants in both groups completed the procedures. There were no ablation related complications. The mean follow-up time was 16.6 ± 5.2 months (range 6 to 26). Overall survival was 100% and the actuarial freedom from stroke was 100%. There was 1 death that occurred 3 months after surgery in the control group.

Recently, some surgeons have used radiofrequency energy, microwaves and cryoprobes to create atrial lesions instead of the scalpel incisional technique used in the traditional Maze procedure. The resulting return of sustained sinus rhythm has been between 44% and 92% in various studies (Beukema, 2008). Khargi and colleagues (2007) performed a systematic review of 48 eligible studies to compare the surgical treatment utilizing alternative energy sources (Group 1) with the classical cut-and-sew Cox-Maze III procedure (Group 2). The authors noted an unexpected and significant difference in mean age of 6.2 years between the cohorts (61.2 yrs versus 55.0 yrs, respectively). In addition, atrial fibrillation alone (19.3%) was the primary indication for Group 2, compared to 1.6% of the participants in Group 1. After adjustment for the type of arrhythmia and type of surgery, there was no significant difference in the post-operative sinus rhythm conversion rate between the groups (p=0.260).  

Weimar and colleagues (2011) reported results from a case series of 100 participants treated with Cox-Maze procedure IV (CMP-IV), which is the modified Cox-Maze III procedure utilizing bipolar radiofrequency and cryoenergy, to create the linear ablation lines. The CMP-IV procedure included isolation of the pulmonary vein with either the box lesion or the non-box lesion set. The mean followup was 17 ± 10 months and freedom from AF at 6-, 12- and 24-months was 93%, 90% and 90% respectively. In addition, freedom from AF while off of antiarrhythmic medication was 82%, 82% and 84% at 6-, 12- and 24-months. The overall 30-day mortality rate was 1%. Subset analysis at 1-year for the complete box lesion set (n=78), resulted in 96% freedom from AF and 86% were off of antiarrhythmic drugs. Participants treated with the non-box lesion set (n=22) had 79% freedom from AF and 47% were off of antiarrhythmic drugs at 1-year.

There is evidence from a number of prospective and retrospective studies that the Maze procedure is effective in restoring sinus rhythm in the majority of participants with medically refractory, chronic, symptomatic atrial fibrillation, in whom rhythm control is considered essential. The Institute for Clinical Systems Improvement (ICSI, 2008) healthcare guideline on atrial fibrillation noted, "the surgical Maze-III procedure has served as the template and gold standard on which to base efficacy and morbidity of subsequent ablation techniques over the last three decades." In addition, there is some evidence that, when performed in conjunction with valve repair or replacement, the Maze procedure may reduce the risk of stroke compared with valve replacement alone. While some mortality is associated with this procedure, study results suggest that it adds little or no additional risk when performed simultaneously with other open heart surgeries such as valvular repair or replacement.

In case series of individuals with medically refractory atrial fibrillation or flutter, the Maze procedure has restored the normal function of the atrium by eliminating the arrhythmia, eliminating the underlying pathophysiology of thrombus formation and restoring the atrial kick to the cardiac output.

The American College of Cardiology (ACC; Fuster, 2006) endorsed and published guidelines for the management of atrial fibrillation in 2006 which state that consideration should be given to concomitant Maze surgery for individuals with highly symptomatic atrial fibrillation and who require open heart operations for valvular, ischemic, or congenital heart disease.

On January 25, 2002, the FDA approved the Medtronic^® Cardioblate^™ System (Medtronic Inc., Minneapolis, MN) which uses radiofrequency energy to ablate cardiac tissue. On January 29, 2003 the Cardima^® Ablation System (Cardima, Inc. Fremont, CA) received FDA approval, as substantially equivalent to the Medtronic device, amongst others which are also FDA-approved for performing ablation of cardiac tissue.

Peer Reviewed Publications:

1. Ballaux PK, Geuzebroek GS, van Hemel NM, et al. Freedom from atrial arrhythmias after classic maze III surgery: a 10-year experience. J Thorac Cardiovasc Surg. 2006; 132(6):1433-1440.
2. Bando K, Kobayashi J, Kosakai Y, et al. Impact of Cox maze procedure on outcome in patients with atrial fibrillation and mitral valve disease. J Thorac Cardiovasc Surg. 2002; 124(3):575-583.
3. Beukema WP, Sie HT, Misier AR, et al. Intermediate to long-term results of radiofrequency modified maze procedure as an adjunct to open-heart surgery. Ann Thorac Surg. 2008; 86(5):1409-1414.
4. Cox JL. Intraoperative options for treating atrial fibrillation associated with mitral valve disease. J Thorac Cardiovasc Surg. 2001; 122(2):212-215.
5. Cui YQ, Sun LB, Li Y, et al. Intraoperative modified Cox mini-Maze procedure for long-standing persistent atrial fibrillation. Ann Torac Surg. 2008; 85(4):1283- 1289.
6. Damiano RJ Jr., Schuessler RB, Voeller RK. Surgical treatment of atrial fibrillation: a look into the future. Semin Thorac Cardiovasc Surg. 2007; 19(1):39-45.
7. Falk RH. Management of atrial fibrillation—radical reform or modest modification? N Engl J Med. 2002; 347(23):1883-1884.
8. Khargi K, Keyhan-Falsafi A, Hutten BA. Surgical treatment of atrial fibrillation: a systematic review. Herzschrittmacherther Elektrophysiol. 2007; 18(2):68-76.
9. Kong MH, Lopes RD, Piccini JP, et al. Surgical Maze procedure as a treatment for atrial fibrillation: a meta-analysis of randomized controlled trials. Cardiovasc Ther. 2010; 28(5):311-326.
10. Lonnerholm S, Blomstrom P, Nilsson L, et al. Effects of the maze operation on health-related quality of life in patients with atrial fibrillation. Circulation. 2000; 101(22):2607-2611.
11. Reston JT, Shuhaiber JH. Meta-analysis of clinical outcomes of maze-related surgical procedures for medically refractory atrial fibrillation. Eur J Cardiothorac Surg. 2005; 28(5):724-730.
12. Saltman AE, Gillinov AM. Surgical approaches for atrial fibrillation. Cardiol Clin. 2009; 27(1):179-188.
13. Stulak JM, Dearani JA, Sundt TM 3rd, et al. Ablation of Atrial Fibrillation: Comparison of Catheter-Based Techniques and the Cox-Maze III Operation. Ann Thorac Surg. 2011; 91(6):1882-1889.
14. Weimar T, Bailey MS, Watanabe Y, et al. The Cox-maze IV procedure for lone atrial fibrillation: a single center experience in 100 consecutive patients. J Interv Card Electrophysiol. 2011; 31(1):47-54.
15. Wyse DG, Waldo AL, DiMarco JP, et al. The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) Investigators. A comparison of rate control and rhythm control in patients with atrial fibrillation. N Engl J Med. 2002; 347(23):1825-1833.

Government Agency, Medical Society, and Other Authoritative Publications:

1. Fuster V, Ryden LE, Cannom DS, et al. ACC/AHA/ESC 2006 Guidelines for the Management of Patients with Atrial Fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients with Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. Circulation. 2006; 114(7):e257-e354.
2. Institute for Clinical Systems Improvement (ICSI). Healthcare guideline: atrial fibrillation. October 2008. Available at: http://www.icsi.org/atrial_fibrillation__guideline_/atrial_fibrillation__guideline__38782.html. Accessed on June 21, 2011.
3. U.S. Food and Drug Administration 510(k) Premarket Notification Database. Cardimal, Inc. Cardima Ablation System. No. K022008. Rockville, MD: FDA. January 23, 2003. Available at: http://www.accessdata.fda.gov/cdrh_docs/pdf2/K022008.pdf. Accessed on June 21, 2011.
4. U.S. Food and Drug Administration 510(k) Premarket Notification Database. Medtronic, Inc. Medtronic Cardioblate Radiofrequency Ablation System. No. K013392. Rockville, MD: FDA. January 25, 2002. Available at: http://www.accessdata.fda.gov/cdrh_docs/pdf/K013392.pdf. Accessed on June 21, 2011.

Atrial Fibrillation, Maze Procedure for
Cox Maze III
Maze Procedure