Aim: The aim of the study was to evaluate the effects of glycoprotein (GP) IIb/IIIa inhibition on minor myocardial injury characterized by cardiac troponin I (cTn-I) and cardiac troponin T (cTn-T) elevation after elective successful percutaneous coronary intervention (PCI). Methods: The study consisted of 119 consecutive patients scheduled for elective coronary balloon angioplasty with or without stent implantation. Sixty-three patients (mean age 58 ± 9.4 years) were randomized to receive standard therapy, including preprocedural aspirin, ticlopidine and intravenous heparin, and 56 patients (mean age 55 ± 9.6 years) were randomized to additionally receive intravenous tirofiban infusion. cTn-I, cTn-T and CK-MB were measured before and immediately after the procedure, and every 6 h for the first 24 h. A total of 128 stenoses were treated with PCI. Seventy of these lesions were in the standard therapy group and 58 in the tirofiban group. Results: The frequency of postprocedural abnormal cTn-I levels was significantly higher in the standard therapy group than that in the tirofiban group (37 vs. 16%; p = 0.017). Postprocedural cTn-T elevation occurred in 23% of patients in the standard therapy group and in 8% of patients in the tirofiban group (p = 0.037). The frequencies of CK-MB elevation higher than the upper limit of normal (ULN), and higher than 2 times the ULN were not significantly different between the standard therapy and tirofiban groups (12 vs. 4%, and 7 vs. 2%, respectively). Conclusions: GP IIb/IIIa inhibition may reduce the incidence of minor myocardial injury, which may also be a possible mechanism in reducing long-term cardiac events after PCI.