RESUMO
Patients with ICDs are commonly advised to quit industrial jobs because of concerns that strong electromagnetic fields operating in the industrial environment might interfere with ICD functions. This study was done to assess interactions between industrial equipment and ICDs, and to devise a simple low risk screening protocol. We studied 18 patients carrying nine different ICD models who were met at their workplace by a clinical technician and were asked to walk through their workplace and perform typical duties while sensing status was monitored by listening to the ICD's beeper. All devices were interrogated at the completion of testing. At follow-up, patients were contacted by phone and were asked about employment status and history of ICD discharges or syncope. One hundred eighty-four contacts with 114 types of industrial equipment in 13 different industrial facilities (including 31 contacts with arc welding machines) were monitored. Interference with ICD's function occurred in only one contact (0.5%), when ICD therapy was temporarily suspended while a worker was attaching a huge electromagnet to a crane. At follow-up 46.0 +/- 6.0 months after testing, 7 patients (41%) are still holding the same job, 7 have retired because of reasons unrelated to their ICD, and 3 patients were transferred to a nonindustrial job. None of the patients had either an ICD shock or syncope during work. The use of a simple screening procedure can safely identify sources of electromagnetic interference that may affect ICD operation, and can predict long-term safety of working in an industrial workplace for ICD patients.
