What is a Cox-Maze procedure?

The Cox-Maze procedure was developed to treat and cure atrial fibrillation (A-fib). This is important for several reasons. Restoration of A-V synchrony improves LV systolic function, especially in the setting of poor left-ventricular function. Return to sinus rhythm lowers the risk of stroke, eliminating clot formation within the left atrium. Additionally, patients may be free from requiring lifelong medications such as anti-arrhythmics and anticoagulants. 

 The Cox-Maze procedure (“cut-and-sew”) can be successful in more than 90% of cases, but is rarely performed due to its complexity and technical challenges. A series of complex cuts are performed along known macro re-entrant pathways of both left and right atria. These surgical cuts permanently divide and redirect the atrial wiring, eliminating the propagation of fibrillation and restoring a path for normal sinus conduction. This remains the most successful, reliable, and effective procedure to treat A-fib in the setting of complex valvular and ischemic heart disease. A 2003 study at Washington University in St. Louis showed a greater than 95% cure rate 10 years after a Cox-Maze procedure. 

 Our surgical team has vast experience, having performed more than 400 successful “cut-and-sew” Cox-Maze procedures. Our overall mortality rate for this procedure is 1.5%. Since 1998, we have had zero mortality in our mitral-valve repair population; the mortality rate remains at zero when adding a full cut-and-sew Cox-Maze procedure in patients with associated A-fib. 

 In patients with isolated A-fib, we are now incorporating minimally invasive methods to generate identical Cox-Maze cut-and-sew lesions in both the right and left atria. This extremely effective approach is performed through a mini right thoracotomy and does not depend on further hybrid-type strategies and “touch up” ablations. Until now, patients who have failed multiple catheter-based A-fib ablations and continue to have refractory arrhythmias, or who have not been able to tolerate drug therapy, have had very few, if any, good options. As a result, in patients with no other heart ailment besides A-fib, our less invasive surgical approach offers them the very best chance for a long term cure.

Cox-Maze procedure patient case study

Complex and higher-risk reoperative surgery has become commonplace as patients live longer. This case study involves a patient with chronic A-fib and an opportunity to restore A-V synchrony in the setting of severe LV dysfunction (EF=20%), ostial left main stenosis and ischemic mitral regurgitation.

Patient history

Hongkie Yun, a 72-year-old retired anesthesiologist, presented with a history of prior single-vessel bypass surgery to the LAD 25 years ago. He required multiple interventions secondary to early occlusion of the LIMA graft. He now presents with longstanding A-fib and exertional angina in the setting of decompensated left-ventricular function with reduction of EF to 20%. Left-ventricular dimension at end diastole was 5.2cm. At least moderate mitral regurgitation was present. Cardiac catheterization, performed at an outside institution, confirmed occlusion of the LIMA graft, while revealing ostial left main stenosis and high-grade proximal LAD disease. He was referred by his cardiologist to Dr. Castro at Sequoia Hospital.

Complex Cox-Maze procedure

A redo-sternotomy was performed without complication. Oncardiopulmonary bypass, a full cut-and-sew Cox-Maze procedure was performed, which always includes excision of the left-atrial appendage. In addition, mitral valve repair and complex two-vessel bypass to a deeply intramyocardial LAD, as well as an A-V groove left circumflex was performed. An intra-aortic balloon pump was used to maximize afterload reduction and LV recovery.

When results matter

Nearly a year since Dr. Yun’s operation, he has remained in sinus rhythm and has been taken off coumadin. Most recent echocardiography revealed full recovery of the left ventricle, normalized ejection fraction (60%), and no mitral regurgitation. 

Dr. Yun has returned to his busy life back home. He is golfing, gardening, and enjoying life. “Prior to surgery, my Dad felt tired all the time. Now he feels stronger, younger, and he says his vision is even brighter,” explains his son Paul, a private-practice otolaryngologist. 

Paul has watched his father blossom after his second heart surgery. He says, “My dad feels younger now after surgery and is able to keep up with his eight grandchildren.”