Heart Surgery for Atrial Fibrillation (MAZE)


What is Atrial Fibrillation?

Atrial fibrillation (AF or AFib) is the most common abnormal heart rhythm. Atrial fibrillation is an irregular, frequently rapid heart rhythm originating in the atria (top chambers of the heart). Instead of the normal situation (normal sinus rhythm) in which a single impulse travels in an orderly fashion through the heart, in AF many impulses begin simultaneously and spread through the atria, causing a rapid and disorganized heartbeat. .

At one time, atrial fibrillation was thought to be a harmless annoyance. However, atrial fibrillation is now recognized as a dangerous condition. Atrial fibrillation doubles the risk of death. It also increases the risk of stroke five to seven times compared to a person without atrial fibrillation. In addition, atrial fibrillation may cause congestive heart failure and uncomfortable symptoms related to a rapid heart rate. Learn more about atrial fibrillation (afib).

Advances in ablation (both minimal invasive surgical and catheter) offer the possibility of cure to a large number of patients.

Treatment for Atrial Fibrillation


The goals of treatment for atrial fibrillation include regaining a normal heart rhythm (sinus rhythm), controlling the heart rate, preventing blood clots and reducing the risk of stroke.

Medical Management of Atrial Fibrillation

Initially, medications are used to treat atrial fibrillation. Atrial fibrillation medications may include:

  • Rhythm control medications (antiarrhythmic drugs)
  • Rate control medications (to slow the heart rate)
  • Coumadin (warfarin - an anticoagulant or blood thinner) to prevent blood clots and stroke

Surgical Treatment for Atrial Fibrillation

Surgical treatment for atrial fibrillation is considered when:

  • Medical therapy does not effectively control or correct atrial fibrillation
  • Medications for atrial fibrillation are not tolerated
  • Anticoagulants (coumadin/warfarin) can not be taken
  • Blood clots, including strokes, occur

Minimally invasive surgery is an option for many patients with atrial fibrillation. Surgical treatment for atrial fibrillation also may be considered when surgery is needed to treat a coexisting heart condition, such as valve or coronary artery disease.


To determine if surgical treatment for atrial fibrillation is appropriate, a thorough evaluation will be performed, which includes:

  • A review of your medical history
  • Echocardiogram (echo)
  • Complete physical examination
  • Holter monitor test
  • Electrocardiogram (ECG)
  • Other tests as needed

After the evaluation, the surgeon will discuss your treatment options and together, you will determine if you are a candidate for surgery.

Who is a Candidate for Atrial Fibrillation Surgery?

Dr. Marc Gillinov discusses the results of a randomized controlled trial from the Cardiothoracic Surgical Trials Network and recommends surgical ablation or maze procedure for patients who are having heart surgery and have pre-existing atrial fibrillation.

Cleveland Clinic surgeons have the nation's largest experience in the ablation (cure) of atrial fibrillation. Using the very latest technology, including advanced surgical robotics, Cleveland Clinic heart surgeons can now extend treatment to virtually all patients with atrial fibrillation. Surgical treatment for atrial fibrillation is termed a "Maze" procedure or ablation; other commonly used terms include "mini-Maze" or pulmonary vein isolation.While variations of these procedures are common, at Cleveland Clinic we believe that best results are obtained by using less invasive approaches to perform a procedure that closely resembles the classic Maze procedure. Patients considered for surgical ablation fall into two groups:

  1. Patients with isolated atrial fibrillation - may be candidates for minimally invasive treatment approaches.
  2. Patients with atrial fibrillation who require heart surgery for other reasons, most commonly to treat coronary artery disease or valvular heart disease.

Minimally Invasive Surgery for Patients with Isolated Atrial Fibrillation

Currently, most patients with atrial fibrillation are candidates for minimally invasive surgical ablation. The maze procedure is the surgical ablation approach with the greatest long-term success in treating atrial fibrillation. The maze procedure includes creation of lines of conduction block (scar tissue) that block the abnormal impulses that cause atrial fibrillation, enabling restoration of normal sinus rhythm. The lines of conduction block are created using cryothermy (freezing) or radiofrequency energy. Surgical ablation also includes exclusion of the left atrial appendage, the primary source of strokes in patients with atrial fibrillation.

The maze procedure is appropriate for patients with highly symptomatic atrial fibrillation, patients in whom catheter ablation has failed, and patients who have a history of stroke or other blood clots. The success rate is approximately 80% to 90%, varying with patient characteristics.

Patients with Atrial Fibrillation Who Require Other Heart Surgery

Atrial fibrillation is very common in patients who require heart surgery for other reasons (such as mitral valve surgery, aortic valve surgery, coronary artery bypass grafting, and other surgical procedures). Recent data from Cleveland Clinic demonstrate that untreated atrial fibrillation in such patients increases mortality (see graphs below). Therefore, in patients with a history of atrial fibrillation, Cleveland Clinic surgeons treat the atrial fibrillation during other types of cardiac surgery.

Survival After Heart Surgery


Atrial fibrillation surgery combined with mitral valve repair

Patients with untreated preoperative AF (blue lines) have reduced survival. Now, all AF is ablated at the time of heart surgery.

When patients with AF have valve or bypass surgery, surgeons create a classic Maze lesion set on the heart using either radiofrequency energy or cryothermy. This generally adds 15 minutes to the operative procedure and does not increase operative risk. Sinus rhythm is restored in 75% to 85% of patients, depending upon patient characteristics.

Selected patients with valvular heart disease and atrial fibrillation may be candidates for a minimally invasive approach that enables treatment of both conditions.

This information is about procedures and may include instructions specific to Cleveland Clinic. Please consult your physician for information pertaining to your specific procedure.

Procedure Details

Before the Procedure

For most patients, surgery for atrial fibrillation is elective. This allows you to qualify for our TCI program. TCI stands for To Come In and allows patients to arrive at Cleveland Clinic on the same day as their scheduled surgery, instead of being admitted several days before. Before your scheduled surgery date, you will have a preoperative appointment to:

  • Receive specific instructions to help you prepare for surgery. Information about eating, drinking and taking medications prior to surgery will be discussed.
  • Meet with your anesthesiologist, nurse clinician, cardiologist and surgeon.
  • Discuss your surgery and have an opportunity to ask questions.

Patients admitted to the hospital prior to surgery will receive details of pre-surgical procedures and preparation from their cardiologist and surgeon.

What happens during the surgery?

During minimally invasive surgery, the surgeon views the epicardial (outer) surface of the heart using an endoscope. Specialized instruments are used to isolate the pulmonary veins and create the other lines of conduction block. Unlike traditional heart surgery, there is no large chest wall incision. Therefore, recovery is rapid.

Because the surgeon can view the outside of the heart, the risk of pulmonary vein stenosis is nearly eliminated. In addition, no catheters are introduced into the left side of the beating heart, reducing the risk of blood clots and strokes.

The left atrial appendage is a small, ear-shaped tissue flap located in the left atrium. This tissue is a common source of blood clots in patients who have atrial fibrillation. During surgical procedures to treat atrial fibrillation, the left atrial appendage is either excluded or removed, reducing the risk of late stroke.

After the Procedure

The patient is transferred to an intensive care unit (ICU) for close monitoring for one to two days after the surgery. The patient is then transferred to a private room on a regular nursing unit. Most patients can leave the hospital in 4 days after minimally invasive surgery, this will be longer for combined surgery; return to full activity is generally possible within 3 to 6 weeks.

Thirty to fifty percent of patients experience skipped heartbeats or short episodes of atrial fibrillation during the first three months after the procedure. This is common due to inflammation (swelling) of the atrial tissue and is treated with medications. After the heart has healed, these abnormal heartbeats should subside.

A small number of patients (about six percent) require a pacemaker after surgery due to an underlying rhythm, such as sick sinus syndrome or heart block, which previously was undetected.

Medications after surgery may include:

  • Anticoagulant (blood thinner), such as Coumadin, to prevent blood clots
  • Antiarrhythmic medication to control abnormal heartbeats
  • Diuretic to reduce fluid retention
  • Other medications as needed

Your doctor will monitor your recovery and determine when or if these medications can be discontinued.

Recovery and Outlook

Will you need to follow-up with a cardiologist?

You will return to Cleveland Clinic’s post surgery clinic as well as your local doctor within one week of being discharged from the hospital to ensure you are healing properly. You will then follow-up with your cardiologist within 4-6 weeks of being discharged to check on your heart rhythm and again to ensure you are healing properly. We recommend that you have an EKG at 3 months, 6 months, and 12 months after surgery and then annually thereafter. In addition, we recommend a longer term heart rhythm monitor (called a Holter monitor) at 6 months and 1 year. We would appreciate it if you would ask your doctor to send a copy of the EKG and Holter monitor to Cleveland Clinic to add to your medical records. If you notice atrial fibrillation starting after you are discharged, you will need to see your cardiologist. The Cleveland Clinic staff is happy to work with you, your local doctor and your local cardiologist on helping you recover fully after your surgery. Your post-surgery team will give you a phone number to contact for any post-discharge questions.

Successful Results

Surgeons began performing the Maze procedure at Cleveland Clinic in 1991 and currently have the nation's largest experience with the surgical management of atrial fibrillation. Improvements in surgical techniques over the years have produced successful results in most patients:

  • Rapid recovery from minimally invasive ablation
  • Long-term freedom from atrial fibrillation
  • Decreased symptoms
  • Greatly reduced embolic events (such as blood clots or stroke)
  • Decreased atrial (top chamber of the heart) size in those with enlarged atria pre-surgery, particularly those who undergo Maze procedure with mitral valve repair procedure
  • See our surgical outcomes

You may also use our Secure Online Second Opinion Service using the Internet.

If you are already treated at Cleveland Clinic for atrial fibrillation, talk to your cardiologist about whether surgery is an option for you.


Doctors Who Treat

Doctors vary in quality due to differences in training and experience; hospitals differ in the number of services available. The more complex your medical problem, the greater these differences in quality become and the more they matter.

Clearly, the doctor and hospital that you choose for complex, specialized medical care will have a direct impact on how well you do. To help you make this choice, please review our Miller Family Heart, Vascular & Thoracic Institute Outcomes.

Cleveland Clinic Heart, Vascular & Thoracic Institute Cardiologists and Surgeons

Choosing a doctor to treat your abnormal heart rhythm depends on where you are in your diagnosis and treatment. The following Heart, Vascular & Thoracic Institute Sections and Departments treat patients with Arrhythmias:

  • Section of Electrophysiology and Pacing: cardiology evaluation for medical management or electrophysiology procedures or devices - Call Cardiology Appointments at toll-free 800.223.2273, extension 4-6697 or request an appointment online.
  • Department of Thoracic and Cardiovascular Surgery: surgery evaluation for surgical treatment for atrial fibrillation, epicardial lead placement, and in some cases if necessary, lead and device implantation and removal. For more information, please contact us.
  • You may also use our MyConsult second opinion consultation using the Internet.

The Heart, Vascular & Thoracic Institute also has specialized centers to treat certain populations of patients:

For younger patients with abnormal heart rhythms:

See: About Us to learn more about the Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute.


If you need more information,click here to contact us, chat online with a nurse or call the Miller Family Heart, Vascular & Thoracic Institute Resource & Information Nurse at 216.445.9288 or toll-free at 866.289.6911. We would be happy to help you.

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Last reviewed by a Cleveland Clinic medical professional on 05/01/2019.

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