**Acknowledgements**

in overall LVAD infection control within hospitals are also helpful in preventing infections [86–88]. Pocket infections must typically be managed with surgical debridement in the operating room with techniques such as omental wrapping of the pump housing to cover exposed metal and to close surgical defects [89, 90]. In rare instances, extrapolating from the orthopedic surgery literature, antibiotic impregnated beads have been placed in the pocket (reviewed in [91, 92]) although this has not been studied in a rigorous manner. Arguably, tissue levels of parenteral antibiotics are sufficient to treat residual infection once source control has been achieved. Placement of an additional foreign body in the pocket may not be advised, especially since the antibiotic concentrations from the beads will eventually wane, requiring subsequent bead exchange or removal. Repeated exposure to sub-inhibitory concentrations of antibiotic can lead to selection of antibiotic resistant organisms. Indolent pathogens such as *M. chimaera* or in the case of fungal infections may necessitate exchange of the pump and other components that are involved. LVAD endocarditis requires explanation and extended antimicrobial therapy, potentially with lifelong suppression if re-implanted or if cardiac transplantation occurs [42, 48, 50]. Optimal peri-implant antibiotic prophylaxis has not been established in a rigorous trial. However, "best evidence" was provided in a review by Acharya et al. [93] and consists of antibiotic coverage for Staphylococci, Enterococci, *Pseudomonas* and *Candida* spp. They concluded that use of an extended spectrum beta-lactam plus vancomycin in areas where rates of methicillin resistant *S. aureus* are high, a fluoroquinolone, fluconazole and mupirocin ointment (nasal application) in the "peri/post-operative" period (~3 days) was recommended. Prophylactic antibiotics are not recommended to prevent driveline infection after the immediate post-operative period [94].

The development of biventricular or LVAD devices with transcutaneous energy sources ("TETs") will eliminate driveline infections [95]. However, this remains the "holy grail" for developers of mechanical circulatory support devices [96, 97]. Magnetically levitated pumps help reduce the rates of reoperation (and attendant complications like infection) [7]. Changes in size and materials involved in these devices can also reduce risk of thrombosis and enable easier explanation and reimplantation should complications arise [98]. Minimally invasive procedures such as offpump implantation and alternative implant sites may also lead to reduced infection risk [99].

Left ventricular assist device (LVAD) infections are important causes of morbidity and mortality in patients who receive these mechanical circulatory supports as a bridge to transplantation (BTT) or as destination therapy (DT) (for individuals who are not candidates for cardiac transplant). Infections are more common among persons who received pulsatile flow LVADs as opposed to newer continuous flow (CF) devices. Other risk factors for infection include obesity, renal failure, depression and immunosuppression although HIV positive LVAD recipients have not had increased rates of infection in the limited number of recipients to

**7. Future directions**

180 Advanced Concepts in Endocarditis

**8. Conclusions**

The author would like to acknowledge the editor, Dr. Michael Firstenberg and Dr. Robert Bonomo for critical reading and suggestions to improve this manuscript.
