Theoretical risk factors for fistula development:
(1) development of esophageal burns and/or ulceration adjacent to the ablation site
(2) close proximity between the posterior left atrial wall and anterior wall of the eosphagus
(3) high intra-luminal temperature within the esophagus during the ablation procedure
Steps to reduce the risk of fistula formation:
(1) Being aware of the distance between the esophageal and left atrial wall prior to the procedure.
(2) Being aware of the distance between the esophageal and left atrial wall during the procedure.
(3) Continuous monitoring of intraluminal temperature with an intraesophageal temperature probe during the ablation procedure.
(4) Carefully control energy application while the probe is along the posterior wall of the left atrium.
(5) Frequently moving the ablation catheter while applying energy to the posterior wall of the left atrium (i.e., not letting it sit at one point for too long).
An atrio-esophageal fistula may still develop despite maximal precautions, but it should be less severe and detected earlier than if no precautions were taken.
