Penetration of ciprofloxacin into heart valves, myocardium, mediastinal fat, and sternal bone marrow in humans.

The penetration of ciprofloxacin into heart tissue (valve and myocardium), mediastinal fat, and sternal bone marrow was the object of a prospective nonrandomized study involving 36 patients undergoing mitral and/or aortic valve replacement. Patients were divided into two groups of 18. Group 1 patients were administered a single 400-mg intravenous dose of ciprofloxacin over a 1-h period. Group 2 patients received a 750-mg dose of ciprofloxacin orally every 12 h over the 48-h period preceding surgery. In this group, the last dose of ciprofloxacin consisted of an intravenous infusion of 400 mg. Concentrations of ciprofloxacin in plasma and tissue were assayed by high-performance liquid chromatography. Peak and trough levels in plasma were, respectively, 6.19 +/- 1.73 and 0.54 +/- 0.25 micrograms/ml in group 1 patients and 11.59 +/- 3.95 and 0.89 +/- 0.57 micrograms/ml in group 2 patients. Levels of ciprofloxacin in plasma remained significantly higher in group 2 than in group 1 until 12 h postinfusion (P less than 0.05). Concentrations of ciprofloxacin in heart valves and myocardia rose rapidly by 1 h postinfusion and remained greater than the MICs for usually susceptible pathogens for at least 5 h. Peak concentrations in myocardia were achieved by hour 1 and were 31.6 +/- 25.0 micrograms/g for group 1 and 21.8 +/- 13.0 micrograms/g for group 2. Peak concentrations in heart valves, achieved between hours 1 and 3, were 5.8 +/- 3.2 and 8.3 +/- 3.1 micrograms/g for groups 1 and 2, respectively. In both groups, peak concentrations in mediastinal fat were lower and achieved later. These were 3.1 +/- 3.8 micrograms/g in group 1 and 2.0 +/- 1.8 micrograms/gram in group 2 and were achieved between hours 3 and 5 and hours 1 and 3, respectively. In conclusion, the good diffusion of ciprofloxacin into heart tissue warrants its use for the treatment of bacterial endocarditis. On the other hand, low and delayed concentrations in mediastinal fat could limit its value as an antibiotic prophylactic agent in a cardiovascular surgical setting when administered immediately (less than 3 h) before surgery.