Vaccination remains the strongest defense against COVID-19. For more information about where you can schedule a vaccine, be tested for COVID-19 or learn more about the virus, visit

COVID-19 Information
Select the search type
  • Site
  • Web

News Release Archive

25th Anniversary of Milestone Heart Procedure; Updated Approach to AFIB Maintains High Cure Rates

  • March 1, 2012
  • Number of views: 2833

ST. LOUIS - Surgeons at the Washington University and Barnes-Jewish Heart & Vascular Center are celebrating the 25th anniversary of the first Cox Maze procedure, a surgery invented there in 1987 that has become the gold standard surgical treatment for patients suffering from a common heart arrhythmia, atrial fibrillation (AFIB).

“We’ve done this operation longer than anyplace in the world and have taught many surgeons from around the world how to perform it,” says Ralph Damiano, MD, chief of cardiac surgery at Barnes-Jewish and Washington University. “This is a milestone we’re quite proud of.”

Dr. Damiano reports on the center’s experience in treating atrial fibrillation with the Cox Maze in the February 2012 print edition of the journal Circulation, in an article titled, “The Cox-Maze Procedure for Lone Atrial Fibrillation: A Single-Center Experience Over 2 Decades.” He concluded the procedure continues to provide excellent results, even with the simplified, less invasive approach.

“This is the largest series of the surgical treatment of lone AFIB ever reported,” says Dr. Damiano. “The success rate for the Cox Maze IV procedure at Washington University and Barnes-Jewish remains among the best in the world for any interventional treatment of AFIB."

The study compares outcomes for 112 patients who underwent the Cox Maze III to the outcomes of 100 patients who underwent the Cox Maze IV, the updated and simplified version of the procedure that utilizes radiofrequency ablation rather than the traditional “cut and sew” technique. The study supports earlier findings that the Cox Maze IV is as effective as the Cox Maze III, with 90 percent freedom from AFIB after two years, and results in fewer complications. Because of advances in ablation technology, the Cox Maze IV reduces the risk of bleeding and is quicker and easier to perform.

The original procedure was developed at the former Barnes Hospital in 1987 by James Cox, MD, former chief of cardiothoracic surgery at Washington University, to treat patients with atrial fibrillation (AFIB) an abnormality of the heart’s electrical system which affects more than 2.2 million people in the United States. It can cause fatigue, shortness of breath, exercise intolerance and palpitations and can considerably raise stroke risk.

In the early years of Cox Maze, Dr. Cox and his colleagues would create ten precisely placed incisions in the heart muscle, and the resulting scars would create permanent barriers to form a “maze.” Those incisions would interrupt the circular electrical patterns responsible for AFIB and cured over 90 percent of patients.

It was a medical breakthrough, but one challenging for physicians to perform and with a higher than preferred complication rate.

“The older Cox Maze procedure was a complicated operation, and very few surgeons were willing to do it,” says Dr. Damiano. “So we started working on new technology and helped develop an effective ablation device that simplifies the procedure.”

Over the next decade plus, Dr. Damiano began developing new ways to perform Cox Maze. Now on its fourth incarnation, Cox Maze IV, Dr. Damiano uses new technology including a clamp that runs radiofrequency energy and kills the clamped heart muscle but doesn’t divide the muscle. That new modification has greatly simplified the procedure and has made it widely applicable to all patients, while maintaining a cure rate over 90%.

“Our results demonstrate the procedure is much easier to perform, the time to perform the procedure is reduced, and the major complication rate declined by two-thirds,” says Dr. Damiano. “Moreover, it has facilitated a minimally invasive approach that further decreases patient discomfort and complication.”

For more information about atrial fibrillation, visit

Jason Merrill
[email protected]

Rate this article:
No rating
Find a doctor or make an appointment: 866.867.3627
General Information: 314.747.3000
One Barnes-Jewish Plaza
St. Louis, MO 63110
© Copyright 1997-2023, Barnes-Jewish Hospital. All Rights Reserved.