Massive air embolism caused by an atrioesophageal fistula following isolation of the pulmonary veins for atrial fibrillation

Key Teaching Points•Massive air embolism, especially when multifocal, should raise suspicion for atrioesophageal fistula (AEF) at the first medical contact. History of recent ablation for atrial fibrillation should be actively sought.•AEF might occur even after procedures in which power applied to the posterior left atrial wall is limited, in accordance with current recommendations.•Left atrial thrombosis at or close to the presumed location of the AEF could also occur. •Massive air embolism, especially when multifocal, should raise suspicion for atrioesophageal fistula (AEF) at the first medical contact. History of recent ablation for atrial fibrillation should be actively sought.•AEF might occur even after procedures in which power applied to the posterior left atrial wall is limited, in accordance with current recommendations.•Left atrial thrombosis at or close to the presumed location of the AEF could also occur.