Pericarditis is the most common pericardial disease found in clinical practice, with an incidence of acute pericarditis reported in 27.7 cases per 100,000 subjects per year. Hemodialysis in end stage renal disease (ESRD) is associated with frequent cardiovascular modifications, mostly because of the highly fluctuating levels of potassium, magnesium, ionized calcium, sodium and volume status. The risk of arrhythmias is increased and chronic atrial fibrillation (AF) can be found among approximately 14% of patients. The renal disease combined with arrhythmias increases the risk of systemic thromboembolism but also of bleeding events. Here we present the case of a male patient, with ESRD, recently diagnosed with intradialytic paroxysmal AF for which oral anticoagulation therapy is initiated, but it's early complicated with hemorrhagic pleural-pericarditis.