Objective To evaluate the efficacy of daptomycin in the treatment of left-sided infective endocarditis after failing to respond to vancomycin.Methods A retrospective analysis was conducted for 6 cases of infective endocarditis.Results Five of the six infective endocarditis patients were complicated with paravalvular abscess (artificial valve in 3 cases,native valve in 2 cases).Their disease deteriorated even under vancomycin treatment.Four of these patients received emergency valve replacement surgery but still febrile after operation.The antimicrobial therapy was switched to daptomycin at dose of 6 mg/kg daily for 2 to 4 weeks.The patients responded satisfactorily to daptomycin.The infection was controlled to some extent in the fifth patient after switching to daptomycin,but recurred later,and died suddenly on day 21 after reoperation.The sixth patient had infective endocarditis of native valve,and had treated with piperacillin-tazobactam for 2 weeks and vancomycin for 3 weeks,but responded poorly.The patient still had fever and enlarged vegetation.Switching to daptomycin reduced the body temperature and vegetation.Serum creatine kinase elevated moderately in one patient,and normal in the other 5 patients.No other apparent adverse reaction was reported.One patient died and the other five patient survived well for 18 months to 5 years.Conclusions Preliminary observation demonstrates the efficacy of daptomycin salvage treatment in a few cases of left-sided infective endocarditis after failing to respond to vancomycin therapy.