The Effect of Microwave and Bipolar Radio-Frequency Ablation in the Surgical Treatment of Permanent Atrial Fibrillation during Valve Surgery

Abstract

Background: Atrial fibrillation (AF) is a frequent problem in patients undergoing valve surgery. This study compared microwave and bipolar radio-frequency ablation of the left atrium in AF patients undergoing valve surgery. Methods: Patients who required left atrial ablation for permanent AF (duration > 6 months) during valve surgery were randomized to a microwave group (n = 94) or a radio-frequency group (n = 93). Regular follow-up was carried out at 3, 6, 9 and 12 months post-procedure and annually thereafter. Results: There were 4 postoperative deaths in the microwave group and 2 in the radio-frequency group. The median follow-up for all patients was 24.0 months (range: 12–36.0 months). Freedom from AF recurrence was significantly higher in the radio-frequency group than in the microwave group at 3 months (85.7 vs. 72.2 %, p = 0.026), 6 months (87.9 vs. 73.3 %%, p = 0.013), 9 months (84.6 vs. 68.9 %, p = 0.012), 12 months (84.6 vs. 67.8 %%, p = 0.008), and 24 months (88.7 vs. 71.2 %, p = 0.022) and at the latest follow-up (81.3 vs. 65.6 %, p = 0.016). Conclusion: Bipolar radio-frequency ablation is superior to microwave ablation for the treatment of permanent AF in patients undergoing valve surgery.

Key words

atrial fibrillation - ablation - surgery

References

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