The Maze operation - surgical therapy for chronic atrial fibrillation: modification to the Mini-Maze procedure

Objective:Atrial fibrillation (AF) is the most common arrhythmia. However, its precise electrophysiologic mechanism is still not well understood. Chro nic symptomatic atrial fibrillation resistant to medical therapy can succes sfully be treated by the Maze III procedure (M III). Several publications a re dealing with alternative surgical techniques. This study describes techn ique and midterm results of a Mini-variant (Mini) of the Maze III procedure . Methods: During a 48-month period we performed either a M III (group I = 7 patients) or a Mini-Maze operation (group II = 65 patients) in 33 males and 39 females with chronic symptomatic atrial fibrillation and additional car diac pathology. Patients were controlled 4.0 +/- 1.8 months (group I) respe ctively 3.6 +/- 0.8 months (group II) (NS) and 16.75 +/- 2.5 months (group I) respectively 13.2 +/- 1.9 months (group II) (NS) after operation by mean s of thorough electrophysiological assessment, right heart catheterization, MRI, echocardiography, stress-EGG and 24h-ECG. Results: There was no significant difference between the two groups with re gard to sex, age and duration of AF. Echocardiographic left atrial diameter (LAD) was 75 +/- 11 mm in group I and 65 +/- 8 mm in group II (p = 0.002). Whereas right atrial diameter was 62 +/- 8 mm in group I and 57 +/- 7 mm i n group II(NS). Perioperative data (n = 72): Aortic cross clamp time was 12 7 +/- 40 min in group I and 87 +/- 22 min in group II (p = 0.0002). Cardiop ulmonary bypass time was 185 +/- 71 min in group I and 137 +/- 42 min in gr oup II (p = 0.01). Postoperative data I (first follow-up: n = 66): sinus rh ythm (yes): 4/7 vs. 47/59 (NS); pacemaker (PM) in AAI mode (yes): 1/7 vs. 3 /59 (NS); inducible atrial fibrillation (yes): 2/7 vs. 5/59 (NS); Bradycard ie Tachycardie Syndrome with the need of PM implantation 0/7 vs. 4/59 (NS). Postoperative data II (second follow-up: n = 55): sinus rhythm (yes): 5/7 vs. 34/48 (NS); PM in AAI mode (yes): 0/7 vs. 4/48 (NS); Inducible atrial f ibrillation (yes): 2/7 vs. 5/48 (NS); Bradycardia Tachycardia Syndrome with the need of PM Implantation 0/7 vs. 5/48. Conclusion: Midterm results are identical after M III and Mini. The Mini-Ma ze procedure is less complex compared to the Maze III procedure and there i s a significant reduction of crossclamp and ECC times. We recommend the Min i especially for polymorbid patients and for those with poor left ventricul ar function.