The occlusion devices used for repair of atrial septal defect and patent foramen ovale commonly contain nitinol, an alloy containing nickel. There are reports of nickel allergy in the context of intracardiac device implantation. Type IV delayed-type reactions likely predominate in intracardiac metal hypersensitivity, but there are potentially other mechanisms such as cytotoxic or innate immunity. Based on available literature to date, the significance of nickel allergy in intracardiac occluders remains unclear.

The aim of the study was to investigate nickel allergy management strategies in intracardiac occluders.

The American Contact Dermatitis Society facilitated distribution of a survey via e-mail to the members of its association, which included dermatologists and allergists/immunologists. A total of 70 individuals answered the survey.

There was no consensus regarding the ability of patch testing to accurately determine allergic reactions within cardiac tissue. There was also no agreement on the criteria for patch testing in patients undergoing intracardiac implantation. However, most would inquire about a history of contact sensitivity to previously implanted devices. With a positive patch test, nickel-based intracardiac devices should be avoided, or the decision should be left to the discretion of the cardiologist.