Minimizing Atrioesophageal Fistula Risk After AF Ablation: Risk Factors, Prevention, and Emerging Mini-Thermal Technology.

Atrial esophageal fistula (AEF) is a rare but life-threatening complication of atrial fibrillation (AF) ablation, linked to thermal injuries by conventional radiofrequency (RF) and cryo-balloon (CB) ablation techniques. AEF risk can be mitigated by considering several measures such as tailored power settings of ablation technique, mechanical displacement of esophagus, esophageal cooling, and alternative ablative techniques and energy sources. We review the current knowledge regarding AEF and esophageal thermal injuries as well as discussing the current research regarding a novel none-to-minimally thermal, myocardial tissue-selective modality known as pulsed-field ablation (PFA) which may mitigate such risks. By inducing irreversible electroporation, PFA reduces thermal injury and demonstrates improved safety profiles, as evidenced by recent meta-analyses reporting zero esophageal injury and AEF cases. Additionally, the integration of 3D mapping systems with PFA has enhanced its procedural precision and accuracy while lowering the radiation exposure. Despite these advances, challenges such as standardizing anesthesia protocols and tailoring energy settings remain. Our review suggests that PFA may reduce the risk of AEF from catheter ablation of AF. While early outcomes of PFA are encouraging, it is important to recognize that preliminary data may not always be predictive of long-term AEF formation risk, as demonstrated by earlier experiences with CB ablation. Although PFA may reduce the risk of any aberrant thermal injuries, recent studies report significant increase in collateral damage including hemolysis, exaggerated troponin leak and coronary vasospasms. PFA should be used with caution in patients with hemolytic anemia or renal dysfunction, as they may experience more pronounced effects. Future long-term outcome studies should provide more information on possible adverse outcomes with PFA as well as tailoring the power settings of PFA.