Objective: Atrial fibrillation (AF) is the most common arrhythmia. However, its precise electrophysiologic mechanism is still not well understood. Chronic symptomatic AF resistant to medical therapy, can successfully be treated by the Maze III procedure (M III). However, there are several publications dealing with alternative surgical techniques. This study describes technique and midterm results of a Mini-variant of the M III procedure.
Methods: During a 38-month period we performed either an M III (seven patients) (group I) or a MINI-operation (45 patients) (group II) with chronic symptomatic AF and additional cardiac pathology. Patients were controlled 3.6 +/- 0.9 and 14.9 +/- 2.2 months after operation by means of thorough electrophysiological assessment, right heart catheterization, magnetic resonance imaging (MRI), echocardiography, stress-EGG and 24-h-ECG.
Results: There was no significant differences between the two groups with regard to sex, age and duration of AF. Echocardiographic left atrial diameter (LAD) was 75 +/- 11 mm in group I and 67 +/- 8 mm in group II (P = 0.01). Whereas right atrial diameter was 62 +/- 8 mm in group I and 56 +/- 7 mm in group II (NS). Perioperative data (n = 52): aortic cross clamp time was 127 +/- 40 mm in group I and 87 +/- 21 mm in group II, (P = 0.0002). Cardiopulmonary bypass time was 185 +/- 71 mm in group I and 137 +/- 46 mm in group II, (P = 0.02). Postoperative data: there was no difference between the two groups with regard to sinus rhythm, prolonged sinus node recovery time, pacemaker (PM) in AAI-mode, inducible atrial fibrillation, reduction of left and right atrial size after a follow-up interval of 3.6 months and 1 year, respectively.
Conclusion: Midterm results are identical after M III and MINI. MINI is less complex compared to the M III procedure and there is a significant reduction of crossclamp- and ECC-time. We recommend the MINI especially for polymorbid patients, and for those with poor left ventricular function.