Kounis Syndrome Acute coronary syndrome (symptoms such as chest pain relating to reduced blood flow to the heart) caused by an allergic reaction or a strong immune reaction to a drug or other substance. Mast cell activation and release of inflammatory cytokines as well as other inflammatory agents from the reaction leads to spasm of the artery leading to the heart muscle or a plaque breaking free and blocking that artery. #Diagnosis #Kounis #Syndrome #Allergic #ACS #Anaphylaxis