We conducted a randomized, controlled clinical trial to determine whether a difference in catheter-associated blood stream infection (CABSI) incidence existed between children who underwent cardiac surgery and had a central venous catheter impregnated with minocycline and rifampin versus those who had a conventional, nonimpregnated catheter after cardiac surgery. Due to a lower number of infections than expected, the study was terminated early. Among 288 evaluable patients, the rates of CABSI and line-related complications were similar between the 2 groups.