Background: Current guidelines for antimicrobial surgical prophylaxis in ventricular assist device (VAD) patients recommend single-agent cefazolin for either single dose or <24 hr continuation. In the clinical setting, prophylaxis choices for VAD patients historically included broader spectrum agents due to high morbidity and mortality associated with VAD infections. At the University of Maryland, antibiotic choice for surgical prophylaxis in VAD patients historically included broad gram-positive and gram-negative (including Pseudomonas) coverage, often vancomycin/piperacillin-tazobactam, for prolonged periods – increasing risk of antimicrobial resistance. In Oct. 2013, UMMC established standardized prophylaxis protocol for VAD patients: vancomycin + ceftriaxone for 72 hrs. Objective: To evaluate rate of surgical site infection (SSI) in VAD patients after implementation of this protocol