For each patient, historical, clinical, and laboratory data were obtained. The historical data included age, sex, race, presence or absence of congenital heart disease, prosthetic valves, indwelling central venous catheters, immunocompromised status, and history of rheumatic fever or drug abuse. Records of history and physical examination near the time of request of TTE were reviewed. These data included the presence or absence of fever (temperature 38°C orally or 38.5°C rectally) and its duration, malaise, rash, vascular and embolic phenomena (petechiae, splinter hemorrhages, Janeway lesions, conjunctival hemorrhages, Roth spots, aseptic meningitis, Osler nodes, and pulmonary, central nervous system, or peripheral emboli), hepatosplenomegaly, congestive heart failure, and the presence of a new heart murmur or a change in the quality of an existing murmur. Malaise was defined as fatigue and a general feeling of being seriously ill described subjectively by the patient or his or her parent and an ill appearance as described by the examining physician. Laboratory data included blood cultures (number of cultures and type of organisms), hematocrit (anemia defined as <0.30), white blood cell count (leukocytosis >15 × 109/L white blood cells), hematuria (>5 red blood cells per high-power field), erythrocyte sedimentation rate, and serum rheumatoid factor.