We present a case of a 50 year-old woman who was referred to our department with severe symptomatic aortic stenosis and systemic mastocytosis. Conventional mechanical aortic valve replacement was performed successfully with the use of perioperative protocol based on dexamethasone, cetirizine and ranitidine. The only postoperative event was an onset of atrial fibrillation which was treated with amiodarone infusion. 8 days after surgery the patient was discharged home