A 57-year-old obese man with hypertensive heart disease and long-standing varicose veins developed recurrent bouts of fever, lung infiltrations, cardiac arrhythmias and increasing dyspnoea. On admission multiple lung emboli and bilateral deep vein thromboses were confirmed. The echocardiogram demonstrated floating vegetations on all three pulmonary valve cusps. Biochemical tests indicated an inflammatory constellation (ESR 62/105 mm, C-reactive protein 13.3 mg/dl), partial respiratory insufficiency (pO2 54.6 mm Hg; pCO2 29 mm Hg). Streptococcus bovis was grown from several blood cultures. Conservative treatment over several weeks, complicated by "drug fever", with penicillin G (10 mega IU four times daily) and gentamicin (80 mg twice daily intravenously), later vancomycin (500 mg four times daily intravenously), then roxithromycin (150 mg three times daily by mouth), as well as maintenance anticoagulation with heparin (800-1,200 IU/h intravenously, later 15,000 IU subcutaneously twice daily), followed by phenprocoumon, contained the disease. One year after onset of treatment a good functional results had been achieved.