Maze Procedure

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MP 7.01.14

Maze Procedure

Medical Policy
Section Surgery	Original Policy Date 12/1/95	Last Review Status/Date Local policy created/7:2008
Issue 7:2008		Return to Medical Policy Index

Disclaimer

Our medical policies are designed for informational purposes only and are not an authorization, or an explanation of benefits, or a contract. Receipt of benefits is subject to satisfaction of all terms and conditions of the coverage. Medical technology is constantly changing, and we reserve the right to review and update our policies periodically.

Description

The classic Cox maze III procedure is a complex surgical procedure that involves sequential atriotomy incisions that interrupt potential re-entrant circuits that interrupt the aberrant atrial conduction pathways in the heart for patients with atrial fibrillation. The procedure is also intended to preserve atrial function (pumping). It is indicated for patients who do not respond to medical or other surgical antiarrhythmic therapies and is often performed in conjunction with correction of structural cardiac conditions such as valve repair or replacement. This procedure is considered the gold-standard for surgical treatment of drug-resistant atrial fibrillation (AF) with about 90% success rate.

The maze procedure entails making incisions in the heart that:

direct an impulse from the sinoatrial (SA) node to the atrioventricular (AV) node;
preserve activation of the entire atrium; and
block re-entrant impulses that are responsible for atrial fibrillation (AF) or atrial flutter (AFl ).

The classic Cox maze procedure is performed on a non-beating heart during cardiopulmonary bypass. Simplification of the maze procedure has evolved with the use of different ablation tools such as microwave, cryotherapy, ultrasound, and radiofrequency energy sources to create the atrial lesions instead of employing the incisional technique used in the classic maze procedure.

In addition, less invasive, trans-thoracic, endoscopic, off-pump procedures to treat drug-resistant AF are being developed and evaluated.

Atrial fibrillation is a supraventricular tachyarrhythmia, characterized by disorganized atrial activation with ineffective atrial ejection. The underlying mechanism of AF involves interplay between electrical triggering events and the myocardial substrate that permits propagation and maintenance of the aberrant electrical circuit. The most common focal trigger of AF appears to be located within the cardiac muscle that extends into the pulmonary veins. The atria are frequently abnormal in patients with AF and demonstrate enlargement or increased conduction time. Atrial flutter is a variant of atrial fibrillation.

The U.S. Food and Drug Administration (FDA) approved (January 2002) the Medtronic Cardioblate System, which uses radiofrequency (RF) energy to ablate cardiac tissue. The Cardima SAS (Surgical Ablation System) used during mini-thoracotomy received 510(k) approval by the FDA in 2003 as substantially equivalent to the Medtronic device for performing ablation of cardiac tissue with RF energy. Another bipolar RF device approved for use in surgical procedures is manufactured by Aticure, Inc.

Note: This policy does not address percutaneous catheter ablation procedures for treatment of atrial fibrillation. Also, pulmonary vein isolation and ablation as a treatment of atrial fibrillation is covered separately in Policy No. 2.02.19.

Policy

The maze procedure, performed on a non-beating heart during cardiopulmonary bypass with or without concomitant cardiac surgery is considered medically necessary for treatment of drug-resistant atrial fibrillation or flutter.

Minimally invasive, off-pump maze procedures, may be considered medically necessary for treatment of drug-resistant atrial fibrillation or flutter. (Prior authorization is recommended for these procedures)

Policy Guidelines

Published studies on the maze procedure describe drug-resistant AF and AFL patients as having experienced their arrhythmias for an average of 7 or more years and having unsuccessful results with an average of 5 or more antiarrhythmic medications.

Effective in January 1, 2007, CPT code 33253 was replaced with the following 5 new CPT codes specific to the various open and endoscopic maze procedures:

33254: Operative tissue ablation and reconstruction of atria, limited (e.g., modified maze procedure)

33255: Operative tissue ablation and reconstruction of atria, extensive (e.g., maze procedure); without cardiopulmonary bypass

33256: with cardiopulmonary bypass

33265: Endoscopy, surgical; operative tissue ablation and reconstruction of atria, limited (e.g., modified maze procedure), without cardiopulmonary bypass

33266: operative tissue ablation and reconstruction of atria, extensive (e.g., maze procedure), without cardiopulmonary bypass.

Effective January 1, 2008, there are new CPT add-on codes for when the maze procedure is performed at the time of other cardiac procedures:

33257: Operative tissue ablation and reconstruction of atria, performed at the time of other cardiac procedure(s), limited (e.g. modified maze procedure) (List separately in addition to code for primary procedure)

33258: Operative tissue ablation and reconstruction of atria, performed at the time of other cardiac procedure(s), extensive (e.g. maze procedure), without cardiopulmonary bypass (List separately in addition to code for primary procedure)

33259: Operative tissue ablation and reconstruction of atria, performed at the time of other cardiac procedure(s), extensive (e.g. maze procedure), with cardiopulmonary bypass (List separately in addition to code for primary procedure)

Benefit Application

State or federal mandates (e.g., FEP) may dictate that all devices approved by the U.S. Food and Drug Administration (FDA) may not be considered investigational. Therefore, FDA-approved devices may be assessed on the basis of their medical necessity.

Rationale

This policy was initially developed from articles identified from the MEDLINE database for the period of January 1994 through February 1, 1995, and from a TEC Assessment. (1)

This policy was updated with extensive editing in December 2006. Khargi and colleagues analyzed 48 studies comprising 3,832 patients who received surgical treatment of atrial fibrillation using the classic “cut and sew” Cox-maze III technique or an alternative source of energy. (2) They concluded that they could not identify any significant differences in the postoperative sinus rhythm conversion rates between the classical approach and alternative sources of energy. While prospective randomized studies are lacking, the data involve a wide range of ablative patterns and their effects on atrial tissue. Topkara and colleagues reported comparable postoperative rhythm success in use of either radiofrequency (121 patients) or microwave (85 patients) energy in surgical ablation of atrial fibrillation. (3)

Reston and colleagues reviewed 4 randomized controlled trials and 6 comparative studies to determine whether a simultaneous maze procedure reduces the risk of stroke or death in patients with chronic or paroxysmal atrial fibrillation who receive mitral valve surgery. (4) They concluded that the studies support a reduction in stroke rates and a small increased risk in need for pacemakers among patients receiving simultaneous maze procedures. Alternative energy sources, such as radiofrequency, may reduce the risk of postoperative bleeding associated with classic maze incisions.

While studies have evaluated the minimally invasive off-pump epicardial maze procedures, including pulmonary vein isolation via mini-thoracotomy, currently the data are insufficient to reach conclusions about the relative effectiveness of these procedures compared to the classic Cox-maze III approach. (5-7) These studies did not have control (comparison) groups. Also, follow-up was about 6 months, so durability of treatment is uncertain. The Ninet study was a multicenter European study involving 103 patients. (6) The Pruitt study reported on 50 patients; they reported their findings as “initial results.” (7)

2007 - 2008 Update
The policy was updated with a MEDLINE search for October 2006 through April 2008. No studies were identified that would change the policy statements. A study of long-term outcomes after 127 Cox-maze cut and sew procedures in conjunction with mitral valve replacement was identified. (8) Patient disposition was well documented in the analysis. Thirty percent of patients experienced late atrial fibrillation (AF) recurrence at a mean of 44 +/- 27 months. Freedom from AF was 93, 82, 71, and 63% at 1, 3, 5 and 7 years respectively, and pacemakers were implanted in 4.7% of patients.

Several observational studies compared the Cox-Maze III procedure with other procedures (radiofrequency ablation, pulmonary vein isolation) performed at single institutions, with procedure selection guided by the surgeon. Two studies attempted to address the selection bias inherent in these studies by matching. In the first from the Washington University School of Medicine, where the maze procedure was developed, the 242 patients who underwent the Cox-maze procedure (154 with the classic cut and sew (CMIII) procedure, and 88 where radiofrequency ablation replaced the incisions of the classic procedure (CMIV)) were matched on their propensity for treatment assignment (a logistic regression where the outcome is treatment assignment and the predictors are covariates that might influence which procedure is chosen by the surgeon). (9) Fifty-eight matched pairs were studied. At one year, survival was 94% and 89% ('p=0.19) and freedom from AF recurrence was 96% and 93% ('p=0.52) for the CMIII and CMIV groups, respectively. The authors note that the CMIV procedure was offered to higher risk patients than the CMIII procedure, which is partly why only 58 of 88 CMIV patients were able to be matched in their analysis. The matched propensity analysis is able to remove measureable selection biases, but if unmeasured factors lead surgeons to choose one surgery over the other, these factors are not accounted for in the analysis. In a second matched analysis, 56 patients who underwent a CMIV radiofrequency ablation procedure at the Mayo Clinic were matched (historical controls) to 56 patients who underwent the CMIII procedure. (10) Matching factors were age, gender, NYHA class, AF type, and concomitant mitral valve surgery. Here the CMIV group had greater postoperative AF (43% vs. 24%), more pacemaker requirements (25% vs 5%), more antiarrhythmic drug use (75% vs. 25%), and fewer patients with freedom from AF at late follow-up (mean 8.4 months) (62% vs. 92%). Again the CMIV patients had greater underlying disease (more concomitant procedures were performed). These studies do not alter the conclusions noted in the 2006 update that there are not significant differences in the rhythm conversion rates between the classical maze approach and alternative sources of energy.

Pruitt published results on a case series of a minimally invasive thoracoscopic procedure in 100 symptomatic patients with drug-resistant lone AF. (11) The authors concluded that clinical results with the application of microwave energy with this approach have been less than satisfactory; moreover, long-term relief from atrial fibrillation has not been achieved.

References:

TEC Assessments 1994: Tab 19
Khargi K, Hutten BA, Lemke B et al. Surgical treatment of atrial fibrillation: a systematic review. Eur J Cardiothorac Surg 2005; 27(2):258-65.
Topkara VK, Williams MR, Barili F et al. Radiofrequency and microwave energy sources in surgical ablation of atrial fibrillation: a comparative analysis. Heart Surg Forum 2006; 9(3):E614-7.
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):724-30.
Williams MR, Garrido M, Oz MC et al. Alternative energy sources for surgical atrial ablation. J Card Surg 2004; 19(3): 201-6.
Ninet J, Roques X, Seitelberger R et al. Surgical ablation of atrial fibrillation with off-pump, epicardial, high-intensity focused ultrasound: results of a multicenter trial. J Thorac Cardiovasc Surg 2005; 130(3):803-9.
Pruitt JC, Lazzara RR, Dworkin GH et al. Totally endoscopic ablation of lone atrial fibrillation: initial clinical experience. Ann Thorac Surg 2006; 81(4):1325-30.
Kim KC, Cho KR, Kim YJ et al. Long-term results of the Cox-Maze III procedure for persistent atrial fibrillation associated with rheumatic mitral valve disease: 10-year experience. Eur J Cardiothorac Surg 2007; 31(2):261-6.
Lall SC, Melby SJ, Voeller RK et al. The effect of ablation technology on surgical outcomes after the Cox-maze procedure: a propensity analysis. J Thorac Cardiovasc Surg 2007; 133(2):389-96.
Stulak JM, Dearani JA, Sundt TM 3rd et al. Superiority of cut-and-sew technique for the Cox maze procedure: comparison with radiofrequency ablation. J Thorac Cardiovasc Surg 2007; 133(4):1022-7.
Pruitt JC, Lazzara RR, Ebra G. Minimally invasive surgical ablation of atrial fibrillation: The thoracoscopic box lesion approach. J Interv Card Electrophysiol 2007; 20(3):83-7.

Codes	Number	Description
CPT	33253	Operative incisions and reconstruction of atria for treatment of atrial fibrillation or atrial flutter (e.g., maze procedure) (discontinued effective 1/1/07)
	33254	Operative tissue ablation and reconstruction of atria, limited (e.g., modified maze procedure) (new code effective 1/1/07)
	33255	Operative tissue ablation and reconstruction of atria, extensive (e.g., maze procedure); without cardiopulmonary bypass (new code effective 1/1/07)
	33256	Operative tissue ablation and reconstruction of atria, extensive (e.g., maze procedure); with cardiopulmonary bypass (new code effective 1/1/07)
	33257	Operative tissue ablation and reconstruction of atria, performed at the time of other cardiac procedure(s), limited (e.g. modified maze procedure) (List separately in addition to code for primary procedure) (new code 1/1/08)
	33258	Operative tissue ablation and reconstruction of atria, performed at the time of other cardiac procedure(s), extensive (e.g. maze procedure), without cardiopulmonary bypass (List separately in addition to code for primary procedure) (new code 1/1/08)
	33259	Operative tissue ablation and reconstruction of atria, performed at the time of other cardiac procedure(s), extensive (e.g. maze procedure), with cardiopulmonary bypass (List separately in addition to code for primary procedure) (new code 1/1/08)
	33265	Endoscopy, surgical; operative tissue ablation and reconstruction of atria, limited (e.g., modified maze procedure), without cardiopulmonary bypass (new code effective 1/1/07)
	33266	Endoscopy, surgical; operative tissue ablation and reconstruction of atria, extensive (e.g., maze procedure), without cardiopulmonary bypass (new code effective 1/1/07)
ICD-9 Procedure	37.33	Excision or destruction of other lesions or tissue of heart, open approach (includes open maze procedure)
	37.34	Excision or destruction of other lesions or tissue of heart, other approach (includes modified maze procedure, endovascular approach)
ICD-9 Diagnosis	427.31	Atrial fibrillation
	427.32	Atrial or auricular flutter
HCPCS	No Code
Type of Service	Surgery
Place of Service	Inpatient

Index

Maze procedure
Modified maze procedure

Policy History

Date	Action	Reason
12/01/95	Add to Surgery section	New policy
08/18/00	Replace policy	Archived policy
7/12/02	Replace policy	Policy reviewed without literature review; new review date only
10/9/03	Replace policy	Policy reviewed by consensus without literature review; no changes in policy; no further review scheduled.
12/12/06	Replace policy	Policy status changed to annual review with literature search and policy updated with literature search through October 2006. Policy statements updated for newer techniques including off-pump maze procedures. CPT and ICD-9 procedure coding updated. Reference numbers 2-7 added.
05/08/08	Replace policy	Policy updated with literature review; no change in policy statements. Reference numbers 8-11 added.
07/21/08	Replace policy	policy statements updated; removed investigational indications; replaced with may be medically necessary, prior authorization recommended

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