Objective: Microwave ablation (MW) has been established as a safe and efficient procedure for the treatment of permanent atrial fibrillation (pAF) resulting in conversion to sinus rhythm (SR). For further improvement of clinical results, a new ablation line concept has been introduced. We present the first clinical results using this new concept in comparison with the results of previous ablation line concepts.
Methods: Ablation lines were performed using microwave energy (Flex 2 and Flex 4 device). We compared two groups, including patients (pts) with mitral valve disease (MVD), coronary artery disease (CAD), and aortic valve disease (AVD). Group A included 137 patients, age 68.4+/-7.8, with ejection fraction 32-80%, left atrial diameter 52.6+/-9.6 mm, suffering from MVD (n=87), CAD (n=59) or AVD (n=36) with pAF for 6.5+/-9.2 years using the original ablation line concept. Group B included 112 patients, age 68.1+/-8.0, ejection fraction 20-83%, left atrial diameter 53.1+/-8.7 mm with pAF for 6.8+/-7.0 years suffering from MVD (n=72), CAD (n=33) or AVD (n=36) performing a modified ablation line.
Results: Survival rate of group A was 98.5% and 97.3% in group B. In the 6-month follow-up for group A, 62% of patients with MVD, 68% with CAD and 78% with AVD were in SR. For group B, 88% of patients with MVD, 78% with CAD and 85% with AVD were in SR.
Conclusions: MW has become an efficient option with an excellent benefit/risk ratio for the treatment of pAF in patients with other cardio surgical disease. The modified ablation line concept in association with the introduction of a new ablation catheter resulted in a 10% higher success rate. Therefore we have established this new lesion line concept as our standard for microwave ablation.