The present study investigated the relationship between myocardial damage and C-reactive protein (CRP) levels, with no increase in creatine kinase (CK) activity, immediately after the onset of acute myocardial infarction (AMI) in 85 patients with their first reperfused anterior AMI without CK elevation on admission and no ischemic events during hospitalization. Patients were classified into those with low levels (<0.3 mg/dl) of CRP (Group L; n=67) and those with high levels (> or =0.3 mg/dl) of CRP (Group H; n=18). Group H had a higher proportion of patients with a history of preinfarction angina (89 vs 55%, p<0.01), especially unstable angina. SigmaST in leads V1-6 on admission ECG was lower in Group H than in Group L (14+/-7 vs 21+/-13 mm, p<0.05). Predischarge left ventriculography showed that the left ventricular global ejection fraction (55+/-11 vs 48+/-10%, p<0.01) and SD/chord at the left anterior descending artery lesion (-1.7+/-0.9 vs -2.3+/-0.9, p<0.01) were better in Group H. Multivariate analysis demonstrated that both CRP on admission (p=0.011) and preinfarction angina (p=0.002) were independently associated with better regional wall motion (SD/chord >-2.0) before discharge. These results suggest that the clinical situation of elevated CRP immediately after onset is associated with less myocardial damage and better left ventricular function in reperfused anterior AMI.