Acute pericarditis following percutaneous interventional procedures is relatively common. Moreover, cardiac ablation procedures pose an increased risk for the development of acute pericarditis, as they directly target sections of the myocardium. Rarely surgical interventions are indicated in cases of acute pericarditis. Here we present a case of a 61-year-old male presented with excruciating chest pain post-RF ablation for atrial fibrillation. Ct scan showed a moderate amount of pericardial fluid. The patient was diagnosed with pericarditis and successfully treated with a pericardial window. The patient improved clinically and demonstrated increased left ventricular ejection fraction following recovery after the pericardial window. This case demonstrates the potential value and risks of the pericardial window for post-RF ablation pericarditis, complicated with pericardial fluid.