Does the outcome improve after radiofrequency ablation for atrial fibrillation in patients undergoing cardiac surgery? A propensity-matched comparison

Preoperative atrial fibrillation (AF) significantly reduces the survival rate post cardiac surgery. It has been shown that patients in persistent or paroxysmal AF have higher mid- and long-term mortality post cardiac surgery compared with those in sinus rhythm. In this study we aimed to assess whether radiofrequency (RF) ablation during cardiac surgery in these patients improves the survival.

For a period of 5 years (2005-10), we studied all the patients who underwent ablation for AF during cardiac surgery for persistent/paroxysmal AF in our institution. We used RF ablation on 113 patients who had AF for <5 years and where the atrial dimension measured <5.5 cm. A 1:2 propensity matching was performed to adjust for the preoperative and operative characteristics with a group in persistent/paroxysmal AF, who had cardiac surgery during the same period of time (2005-10) and did not undergo ablation. We compared the postoperative outcome and survival rates between the two groups.

Before and after adjusting for the preoperative and operative characteristics, inotropic support, renal failure, stroke, intensive care unit and hospital stay, as well as in-hospital mortality were similar between the two groups. After 5 years the difference in the survival was significant between the groups; 91.1 and 83.2%, with and without ablation, respectively (P value = 0.038).

Despite, the similar postoperative outcome with or without ablation in persistent/paroxysmal AF, 5-year survival was found to be significantly higher with the ablation during cardiac surgery. This improvement can be due to the fall in the incidence of cerebro-vascular events or bleeding with AF or warfarin. Ablation during cardiac surgery is a simple and quick procedure and should be considered if indicated.