Cardiac implantable electronic devices (CIEDs) and allergy.

Advances in cardiac implantable electronic devices (CIEDs) have prolonged life expectancy in various medical settings. However, the issue of hypersensitivity to components of CIEDs is still a concern. Since 1970, allergic reactions to metallic and nonmetallic components of CIEDs have been reported. Hypersensitivity reactions to medical devices are rare and not fully understood. In some cases, diagnosis and treatment are difficult. Cardiologists should always keep in mind pacemaker allergy when a patient appears with wound complications and no signs of infection. Patch testing should be tailored toward the specific biomaterials used in a device, in addition to testing with standard screening allergens in select cases.