Gallium-67 Single-Photon Emission Computed Tomography Affects Management of Infections of Left Ventricular Assist Devices.

Our institution employs gallium-67 single-photon emission computed tomography low-dose CT (Ga-SPECT-CT) to determine the presence and extent of left ventricular assist device (LVAD) infections. We present a retrospective single-center study of 41 LVAD recipients who underwent Ga-SPECT-CT from January 2011 to June 2018 to determine whether Ga-SPECT-CT led to changes in antimicrobial therapy, LVAD revision or exchange, or application for 1A exception. The average age was 56.6 years, predominantly male (80.5%) and diabetic (68.3%), divided between ischemic (48.8%) and nonischemic (51.2%) cardiomyopathy. The majority had HeartMate II devices (82.9%). Device-related infections were classified as possible (12.2%), probable (36.6%), proven (36.6%), or rejected (14.6%). Sensitivity was 68.6% and specificity was 100%. Most VAD-specific infections were percutaneous deep driveline infections (DRIs) (34.1%), and VAD-related infections were primarily bloodstream infections (31.7%). Staphylococcus aureus was the major pathogen isolated. Gallium-67 single-photon emission computed tomography low-dose CT resulted in changes in management in more than half (53.7%) of patients: starting (24.4%) or stopping (17.1%) antimicrobial therapy, LVAD revision (22.0%) or exchange (12.2%), and the application for 1A exception for transplant listing (17.1%). We conclude that Ga-SPECT-CT is an effective modality for determining the presence and extent of LVAD DRIs, and contributed to a change in management in more than half of cases.

False positive hepatitis C antibody test results in left ventricular assist device recipients: increased risk with age and transfusions.

Left ventricular assist devices (LVADs) have been successfully used in patients with heart failure. However, LVADs may trigger immune activation, leading to higher frequencies of autoantibodies. We describe the clinical, epidemiological, and laboratory characteristics of LVAD recipients with false positive hepatitis C (FPHC) serology among 39 consecutive adult LVAD recipients who bridged to heart transplantation from January 2007 to January 2013 at Montefiore Medical Center. FPHC patients were identified as those with post-LVAD positive hepatitis C ELISA antibody tests and negative confirmatory testing with hepatitis C RNA PCR and/or radioimmunoblot assay. Ten (26%) patients previously seronegative for hepatitis C were found to have FPHC after device placement. Of the 39 patients, 32 had HeartMate II devices. The mean age at LVAD placement was 55 years. FPHC correlated with older age at the time of LVAD implantation and with receipt of packed red blood cell transfusions, but not with gender, fresh frozen plasma transfusions, panel reactive antibodies, globulin fraction, rheumatoid factor, or anticardiolipin antibodies. Clinicians should be aware of this increased risk of FPHC in older LVAD patients and those more heavily transfused in order to avoid unnecessary apprehension and possible delay in transplantation. Further studies should be done to evaluate the possible relationship between transfused blood products and immunomodulation.

Role of gallium SPECT-CT in the diagnosis of left ventricular assist device infections.

Infection remains a well-established complication after the placement of left ventricular assist devices (LVADs). Defining the extent of infection is a challenging task as there are few effective imaging modalities and no standardized guidelines regarding imaging in the diagnosis of device-related infections (DRIs). The use of gallium with single photon emission tomography-computed tomography (Ga-SPECT-CT) has not been previously reported in localizing DRIs. We reviewed the charts and images of five patients with LVADs who underwent Ga-SPECT-CT for the diagnosis of various types of DRIs. Gallium SPECT-CT further clarified the extent of infections among LVAD patients, allowing for patient-specific tailored treatments including surgical debridement. Gallium SPECT-CT is a useful tool when diagnosing LVAD infections and could potentially be the imaging modality of choice in the near future. With improved imaging studies, such as Ga-SPECT-CT, allowing for earlier and more accurate diagnoses of DRIs, the outcome of such infections is likely to improve.