Left ventricular assist device-related infections: does the time of onset matter?

A frequent complication of left ventricular assist devices (LVAD) is the LVAD-associated infections (LVADIs). Contamination may occur during initial surgery/admission or at a later time. We studied the clinical manifestations and outcomes of LVADIs depending on the time of the onset. Patients implanted with LVADs at our institution between August 2009 and December 2014 were included. Patients were stratified into 2 groups based on whether the infection occurred early (< 180 days) or late (≥ 180 days) after LVAD implantation. Out of 37 overall LVADI episodes, 16 (43%) and 21 (57%) occurred early or late after device implantation, respectively. Median time to first LVADI was 88 ± 35 vs. 456 ± 187 days between groups. While superficial driveline-related infection was the most common LVADI type for both groups (56 vs. 71%, p = 0.489), driveline drainage was more prevalent in the late group (24 vs. 69%; p = 0.009). Early LVADIs involved more gram-positive flora, mostly Staphylococcus aureus (69 vs. 33%, p = 0.049), whereas late LVADIs involved more gram-negative pathogens, mostly Pseudomonas aueroginosa (25 vs. 57%; p = 0.045). High rates of treatment failure were consistent between groups (88 vs. 71%, p = 0.384). Compared with superficial LVADI, deeper infections were associated with an increase in mortality (13 vs 46%, p = 0.046). We concluded that early onset with likely in-hospital contamination involved more gram-positive flora, whereas late infection involved more gram-negative flora. Regardless of timing, success of antibacterial treatment was dismal, and infection depth correlated with poorer outcomes.