An increasing incidence of bacterial endocarditis has been observed since the beginning of the last decade. An explanation for this fact is the expansion of diagnostic and therapeutic procedures in diverse medical disciplines. In a clinical study performed on 49 consecutive patients undergoing extracorporeal shock wave lithotripsy a 14.3% rate of bacteremia was detected during treatment. The bacterial spectrum consisted of gram-positive cocci, gram-negative cocci, Bacteroides capillosus and Proteus mirabilis. In principle, these results do not call for an antibiotic prophylaxis. Nevertheless, according to the recommendations of the American Heart Association and the Deutsche Gesellschaft für Herz- und Kreislaufforschung, patients with a cardiac risk predisposing to bacterial endocarditis must receive perioperative antibiotic prophylaxis.