Atrio-esophageal fistula is a rare but serious complication of percutaneous transcatheter ablation for atrial fibrillation (AF). Two patients developed this condition after circumferential pulmonary vein ablation (CPVA) in different centers. Both presented with symptoms of endocarditis, including fever, chest pain, and neurological deficits. They experienced multiple gaseous and septic embolic events, leading to cerebral and myocardial damage. One patient survived after emergency surgery, while the other died from systemic embolization. Both had atrio-esophageal fistulas. The fistulas occurred in the posterior wall of the left atrium, likely due to overlapping ablation lines and high radiofrequency energy settings. The risk of this complication is low, but it can be fatal. Diagnosis should be considered in any patient with symptoms of endocarditis after left atrial ablation. Transesophageal echocardiogram is not recommended due to the risk of rapid deterioration. Non-invasive imaging like CT with contrast is preferred. Management requires prompt surgical intervention. Prevention strategies include using lower power and temperature settings during ablation in the posterior wall to avoid excessive tissue damage. The study emphasizes the importance of careful technique and monitoring to minimize the risk of atrio-esophageal fistulas.Atrio-esophageal fistula is a rare but serious complication of percutaneous transcatheter ablation for atrial fibrillation (AF). Two patients developed this condition after circumferential pulmonary vein ablation (CPVA) in different centers. Both presented with symptoms of endocarditis, including fever, chest pain, and neurological deficits. They experienced multiple gaseous and septic embolic events, leading to cerebral and myocardial damage. One patient survived after emergency surgery, while the other died from systemic embolization. Both had atrio-esophageal fistulas. The fistulas occurred in the posterior wall of the left atrium, likely due to overlapping ablation lines and high radiofrequency energy settings. The risk of this complication is low, but it can be fatal. Diagnosis should be considered in any patient with symptoms of endocarditis after left atrial ablation. Transesophageal echocardiogram is not recommended due to the risk of rapid deterioration. Non-invasive imaging like CT with contrast is preferred. Management requires prompt surgical intervention. Prevention strategies include using lower power and temperature settings during ablation in the posterior wall to avoid excessive tissue damage. The study emphasizes the importance of careful technique and monitoring to minimize the risk of atrio-esophageal fistulas.