What are the risks of atrial fibrillation ablation?

Major complications are rare, but can be serious. The most concerning are stroke, atrial esophageal fistula and death. Strokes are usually caused by blood clots in the heart, and therefore we prescribe anticoagulants around the time of ablation. A risk peculiar to atrial fibrillation ablation is damage to the esophagus, which passes directly behind the left atrium. In rare cases, a hole can form between the atrium and the esophagus which can be lethal. We therefore monitor the esophageal temperature during ablation and prescribe acid blockers afterwards to protect the esophagus.