Mini-maze suffices as adjunct to mitral valve surgery in patients with preoperative atrial fibrillation

Mini-Maze and Mitral Valve Surgery. Introduction: After mitral valve (MV) s urgery, preoperative atrial fibrillation (AF) often recurs while cardiovers ion therapy generally fails. Additional Cox maze surgery improves postopera tive arrhythmia outcome, but the extensive nature of such an approach limit s general appliance. We investigated the clinical outcome of a simplified, less extensive Cox maze procedure ("mini-maze") as adjunct to MV surgery. Methods and Results: Thirteen patients with MV disease and preoperative AF were treated with combined surgery (group 1). Nine control patients without previous AF underwent isolated MV surgery (group 2), We retrospectively co mpared the results to findings in 23 patients with preoperative AF who had undergone isolated MV surgery (group 3), In group 1, mini-maze took an addi tional 46 minutes of perfusion time. One 75-year-old patient died of postop erative multiple organ failure. Seven patients showed spontaneously convert ing (within 2 months) postoperative AF. After 1 year, 82% were in sinus rhy thm (SR), No sinus node dysfunction was observed, In group 2, all patients were in SR after 1 year, In group 3, only 53% were in SR after 1 year, desp ite serial cardioversion and antiarrhythmic drug therapy. Exercise toleranc e and heart rate were comparable for groups 1 and 2, Left atrial function w as present in all but one patient in group 1 and in all patients in group 2 (after MV reconstruction). Conclusion: Adding a relatively simple mini-maze to MV surgery improves arr hythmia outcome in patients with preoperative AF without introducing sinus node dysfunction or persistent absence of left atrial function. The results of this type of combined surgery are encouraging and deserve further atten tion.