BACKGROUND Pulmonary vein isolation is a method of cardiac ablation therapy used to treat irregular heart rhythm, including atrial fibrillation (AF). This report presents a case of esophagopericardial fistula (EPF) and pneumopericardium as a complication of pulmonary vein isolation in a 62-year-old man with AF. CASE REPORT We report the rare case of a 62-year-old man with a medical history of persistent atrial fibrillation status after ablation 3 days prior to his initial Emergency Department visit for chest pain. Acute coronary syndrome was ruled out with normal electrocardiogram, echocardiography, and troponin tests. Fluid overload and sotalol adverse effects were presumed to be the cause of his symptoms. We discontinued sotalol with diuresis and he was discharged home when his chest pain subsided. Nine days later, he returned to the Emergency Department with worsening similar symptoms and was eventually diagnosed with EPF and pneumopericardium on a computed tomography scan of the chest with contrast. He was managed with esophagogastroduodenoscopy and stent placement along with subxiphoid pericardial window and pericardial drain placement. The patient was discharged in stable condition after removing the pericardial drain. At 10-day and 1-month follow-up, he had no recurrent symptoms. CONCLUSIONS This report shows that although EPF with pneumopericardium is a rare complication of pulmonary vein isolation, it should be rapidly diagnosed and treated as a life-threatening emergency.