Treatment with clarithromycin prior to coronary artery bypass graft surgery does not prevent subsequent cardiac events

Background. Recently, it has been suggested that Chlamydia pneumoniae possibly plays a possible role in the pathogenesis of atherosclerosis. We investigated whether treatment with clarithromycin prior to coronary artery bypass graft (CABG) surgery would prevent subsequent cardiovascular events and mortality. Methods. Patients who were scheduled for CABG surgery were randomly assigned to receive either clarithromycin or placebo until the day of surgery in a double-blind trial. During the 2 years of follow-up, mortality and cardiovascular events were assessed. Results. Follow-up at 2 years was achieved for 473 patients. The mean duration of treatment was 16 days. Patient characteristics at baseline were well balanced between the 2 treatment groups. Mortality was equal in the 2 groups: 10 (4.2%) of 238 patients in the clarithromycin group and 9 ( 3.8%) of 235 patients in the placebo group (relative risk, 1.10; 95% CI, 0.42 - 2.89; P = 1.0). Also, there were no significant differences in the proportion of P = 1.0 patients who experienced cardiovascular events during the follow-up period: 20 (8.4%) of 238 patients in the clarithromycin group and 19 (8.1%) of 235 patients in the placebo group (relative risk, 1.04; 95% CI, 0.55 - 1.98; P = 1.0). The overall rate of such events was 58 (12.3%) of 473 patients. Conclusions. Treatment with clarithromycin in patients scheduled for CABG surgery did not reduce the subsequent occurrence of cardiovascular events or mortality during a 2-year follow- up period.