<prompt> Most common cause of aificial hea valve infection?Staphylococcus aureusStreptococcus mutansStaph epidermidisPneumococcus  <response>: Ans. is c i.e., Staph epidermidis Most common cause of prosthetic valve endocarditis upto 12 months is coagulase - negative staphylococci staph. epidermidis. Most common causes of infective endocarditis In native wall - Staphylococcus aureus. In early prosthetic valve up to 12 months after valve surgery - Staphylococcus epidermidis coagulase negative staphylococcus. In late prosthetic valve more than 12 months after valve surgery - streptococcus viridans. In IV drug abusers - Staphylococcus aureus. In patients with intravenous catheter - coagulase negative staphylococci. After dental procedure tooth extraction - streptococcus mutans. 