In left- heart native valve endocarditis, 4 baseline fea- tures have been independently associated with 6-month mortality: 1) abnormal mental status, 2) moderate to severe HF, 3) bacterial etiology other than Viridans streptococci, and 4) medical therapy without valve surgery. Except in inject- able drug users, the risk of reinfection after prosthetic valve surgery is low relative to the risk associated with not having surgery in patients with hemodynamic and microbial indications for surgery. Prosthetic valve endocarditis is clearly associated with both higher mortality rates (especially with HF, severe valvular dysfunction, or a staphylococcal or fungal infectious microbe) and higher post-treatment HF-related disability. Surgical series report surgical rates of 50% in patients with prosthetic valve endocarditis, and these patients show improved outcomes over medical therapy, even with controlling for sever- ity of illness at time of diagnosis.8,9,15 19 3. Compared with patients with IE attributable to other organisms, patients with left-sided S. aureus IE were significantly more likely to die (20% versus 12%), experience an embolic event (60% versus 31%), have a central nervous sys- tem event (20% versus 13%), and not undergo surgery (26% versus 39%). Staphylococcal pros- thetic valve endocarditis has been associated with a mortality rate as high as 70%, which is driven by resistant staphylococcal species. When Staphylococcus is the bacteria, death occurs in <5% of patients with right-sided native valve Figure 16. Endocarditis treatment. Colors correspond to Table 2. *IE caused by streptococcus, E. faecalis, S. aureus, or coagulase-negative staphylococci deemed stable by the Heart Valve Team. Early surgery defined as during initial hospital course and before completion of a full course of appropriate antibiotics. In patients with an indication for surgery and a stroke but no evidence of intracranial hemorrhage or extensive neurological damage, surgery without delay may be considered. 