Disseminated malignancies masquerading as cardiovascular implantable electronic devices infections

Disruption of a previously well-healed cardiovascular implantable electronic device (CIED) pocket is usually presumed to be secondary to infection and current guidelines recommend the removal of the generator and all leads. We present our experience of CIED pocket disruptions thought to be due to infection and referred to our institution for lead extraction but instead proved to be the first manifestations of disseminated malignancies. Out of 1001 consecutive patients referred to our institution for transvenous lead extraction, two patients were found to have CIED pocket disruptions due to metastatic deposits. In both cases, subjects presented with increased swelling and discomfort of CIED pockets during device follow-up without any signs or symptoms of sepsis and negative cultures. The cause was presumed to be due to infection as it is not uncommon for CIED pocket infections to be diagnosed based purely on clinical appearances of the pocket and negative cultures. Both CIED systems were successfully extracted. At the time of surgery, the scar tissue within the pockets was atypical and histological specimens were sent for analysis. This confirmed diffuse large-cell lymphoma and metastatic lung adenocarcinoma as the causes of CIED pocket disruption. Malignancy should be considered as a differential diagnosis in CIED pocket disruptions, particularly those associated with negative cultures and histological analysis of tissue specimens removed from the pocket should be considered at the time of CIED extraction.