Esophageal injury is a serious complication following atrial fibrillation catheter ablation procedures. It may manifest as atrio-esophageal fistula, pericardio-esophageal fistula (PEF) or restricted perforation with high mortality rate, if left unoperated. Chest computed tomography with intravenous contrast is the mainstay of diagnosis, however a definite imaging diagnosis is often delayed, and may worsen patient outcomes. This case demonstrates that pericardial fluid amylase detection may contribute to early differential diagnosis of PEF versus restricted esophageal perforation combined with inflammatory pericarditis, in patients with relevant symptoms who present with pericardial effusion and may guide either conservative- as our case- or surgical approach.