Pulmonary vein isolation by microwave energy ablation in patients with permanent atrial fibrillation

Atrial fibrillation is associated with significant morbidity and mortality. Microwave energy ablation (MW) is a new option for surgical treatment of permanent atrial fibrillation (pAF). We present our experience with surgical treatment of mitral valve disease (MVD), coronary artery disease (CAD), and aortic valve disease (AVD) and microwave ablation in patients with pAF.

In 202 consecutive patients (100 female, 102 male, age 68.3 +/- 8.1 years from 30.4 to 83.5 years, ejection fraction 25-80%, left atrial diameter 56 +/- 9.1 mm from 30 to 102 mm) with an indication for a cardiosurgical intervention, pAF was documented for 6.8 +/- 9.1 years. MW was performed using two different lesion concepts. In the first 140 patients we used an ablation line starting at the posterior mitral valve annulus and incorporated the interior of all pulmonary veins. After the first 137 patients we switched to a different ablation line concept. Starting at the posterior mitral valve the annulus ablation line additionally included the left atrial appendix. Another ablation circle around the pulmonary veins of both sides was created and both circles were connected. If opening of the right atrium was necessary additional isthmus ablation was performed.

Survival rate was 98.5%. There were no ablation-related complications. In the 6-month follow-up 87 patients were in sinus rhythm (65%), in the 1-year follow-up 74 patients were in SR (62.2%).

Microwave ablation is a safe and efficient method for surgical treatment of pAF in patients with a concomitant cardiosurgical procedure. The short duration for this additional procedure and easy application has made this procedure the method of choice in our institution for treatment of pAF in patients with cardiosurgical operations.