The Cox-maze IV procedure for lone atrial fibrillation: a single center experience in 100 consecutive patients

The Cox-maze III procedure (CMP) has achieved high success rates for the surgical treatment of atrial fibrillation (AF). In 2002, our group introduced a simplified CMP, in which most incisions were replaced with linear lines of ablation using bipolar radiofrequency and cryoenergy. This operation, termed the CMP-IV, has significantly shortened operative times and allowed for a minimally invasive approach. This report evaluates our results in 100 consecutive patients undergoing a stand-alone CMP-IV. Data were collected prospectively on 100 patients (mean age, 56 +/- 10 years) who underwent a CMP-IV from January 2002 through May 2010. All patients were available for follow-up with a mean follow-up of 17 +/- 10 months. Electrocardiograms or 24-h Holter monitorings were obtained at 6, 12, and 24 months. Data were analyzed using a longitudinal database containing over 380 variables. Thirty-one percent of patients had paroxysmal AF, with the remainder having persistent (6%) or longstanding persistent AF (63%). The mean preoperative duration of AF was 7.4 +/- 6.7 years. The mean left atrial diameter was 4.7 +/- 1.1 cm. In this group, 40 patients had failed with a mean of 2.6 +/- 1.3 catheter ablations. Mean aortic cross-clamp time was 41 +/- 13 min. There was one postoperative mortality. Postoperative freedom from AF was 93%, 90%, and 90% at 6, 12, and 24 months, respectively. Freedom from AF off antiarrhythmic medication was 82%, 82%, and 84% at 6, 12, and 24 months, respectively. The less invasive CMP-IV has a high single procedure success rate, even with improved follow-up and stricter definitions of failure.