Colonization With Multiresistant Bacteria: Impact on Ventricular Assist Device Patients

Although the effect of infections with multidrug-resistant bacteria (MDRB) in left ventricular assist device (LVAD) recipients is well characterized, the influence of perioperative colonization on the development of infections in this patient cohort remains unknown. The study evaluated the effect of MDRB colonization on patient outcomes after LVAD implantation.

We retrospectively analyzed the microbiological screening studies of nasal, throat, wound, and rectal swabs in 82 consecutive patients who received an LVAD at our center between 2010 and 2015. Four categories of MDRB were determined: methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and Gram-negative bacterium resistant to three or four of four predefined pharmacologic categories of antibiotics. We also compared the long-term outcome of patients with and without colonization.

There were 28 patients (34.1%) diagnosed as being colonized with at least 1 species of an MDRB. MDRB colonization was associated with the occurrence of fatal infections from any pathogen (MDRB positive, 63.2%; MDRB negative, 34.4%; p = 0.04) and fatal MDRB-specific infections (MDRB positive, 31.6%; MDRB negative, 6.3%; p = 0.04), significantly longer intensive care unit stay (p < 0.0001), and longer cumulative hospital stay (p = 0.04).

Our study demonstrates that the colonization with MDRB is a highly prevalent risk factor for infection-associated death in the vulnerable LVAD population. Routine screening for MDRB before and after LVAD implantation should be considered to identify high-risk individuals and facilitate effective prevention of infectious complications.