Immediate and long-term results of the simultaneous rhythm-converting procedure Cox-Maze IV in multivalvular correction

OBJECTIVE: This study aimed to investigate the immediate and long-term outcomes of the Cox-Maze IV procedure in patients undergoing surgical treatment for multivalvular heart disease with atrial fibrillation. It also sought to identify predictors of atrial fibrillation recurrence in the long-term period. MATERIALS AND METHODS: We conducted an analysis of 92 patients who underwent multivalvular heart defect correction and simultaneous Cox-Maze IV procedure between 2017 and 2023. The mean age of the patients was 65.5 years (57.5; 69), 43 males (46.7%) and 49 females (53.3%). Sixty-six patients (71.7%) were classified as functional class III heart failure according to NYHA, while 3 (3.3%), 14 (15.2%), and 9 (9.8%) were classified as functional classes I, II, and IV, respectively. The types of atrial fibrillation were: paroxysmal in 15.2%, persistent in 22.8%, and long-standing persistent in 62%. The mean duration of atrial fibrillation prior to surgery was 15.5 months (10; 45.8) for those with paroxysmal form, 7 months (4; 9) for persistent form, and 60 months (22; 84) for long-standing persistent form. Mitral-aortic valve replacement was performed in 9 cases (9.8%), mitral-tricuspid correction in 69 cases (75%), and combined mitral-aortic-tricuspid correction in 14 cases (15.2%). RESULTS: During the hospital stay, there were 3 fatalities. In the long-term follow-up, 8 deaths were recorded, with 3 attributed to cardiac causes. Permanent pacemaker implantation was required in just one case during the long-term postoperative period. The freedom from atrial fibrillation was 61.4% in patients with paroxysmal form at follow-up of up to 46 months, 58.1% in those with persistent form at up to 63 months, and 32.5% in those with long-standing persistent form at up to 82 months. Three predictors of arrhythmia recurrence were identified: early postoperative atrial fibrillation paroxysms, a duration of atrial fibrillation exceeding 60 months, and enlarged left atrial size. CONCLUSIONS: The Cox-Maze IV rhythm-conversion procedure designed to restore sustained sinus rhythm is most effective in patients with paroxysmal and persistent forms of atrial fibrillation, achieving success rates of 61.4% and 58.1%, respectively. This procedure is not associated with a high rate of pacemaker implantation. An enlarged left atrium should not deter the use of the Cox-Maze IV procedure in patients with atrial fibrillation; however, atrioplasty is recommended if the left atrium is significantly enlarged. Episodes of rhythm disturbance during the early postoperative period and a history of atrial fibrillation lasting more than 60 months prior to surgery are associated with an increased risk of recurrence postoperatively. Therefore, careful monitoring of these patients after discharge is essential for early detection and management of recurrences.