Atrial fibrillation: Event-recorder based monitoring of MAZE-outcome

Atrial fibrillation (Afib) is the most common cardiac arrhythmia, resulting in stroke, reduced cardiac function, reduction of life expectancy and exercise capacity, increased number of hospitalisations and a doubled mortality rate. Therefore, therapeutic strategies to reduce morbidity and increase quality of life are required. The MAZE-Procedure (MAZE) has become a widely and effectively used stand-alone or additive combined operative therapy for Afib. However, differences in energy sources, ablation lines and follow up procedures result in incommensurable results. Consequently, guidelines for (contra-) indications and definitions of preoperative markers for outcome remain difficult to define. We therefore initiated a prospective follow up study to identify preoperative markers of MAZE-success and perioperative outcome. From 10/2009 to 09/2011 38 patients (13 female/25 male; CABG/AVR/MVR/TVR/combination) underwent MAZE (paroxysmal n=5; chronic n=33). An event recorder was implanted in all those patients. Standardized antiarrhythmic therapy and 6-month-follow up for 2 years was initiated.

30 day mortality in those patients was 6/38 and was neither related to Afib-duration, echocardiographic parameters nor to age but to female sex and high preoperative EuroScore. 54.8% of discharged patients had sinus rhythm independently of preoperative left atrial diameter (p=0.481), LVEF (p=0.973) or primary operative procedure. 11 patients have completed the 6-month follow-up so far. During follow up no mortality or stroke was observed. 81% (n=8) of those patients had sinus rhythm (Afib<1%, periods max <15min), 1 patient gained sinus rhythm after additional interventional catheter ablation, in 1 patient sinus rhythm stabilized with postoperative bradycardia-tachycardia-syndrome after DDD-PM implantation and only one patient (9.09%) retained a therapeutically relevant Afib. Interestingly, procedural success tends to be lower in patients with high body mass index (BMI 27.63±1.56 vs. 33.58±2.16; p=0.057) and periprocedural mortality risk seems to be significantly elevated in females. Thus, identification of preoperative risk markers and continuous follow up of patients may help to improve MAZE long-term success.