Abstract: AIM:To study the changes and the prognostic significance of cardiac troponinⅠ(cTnI) in patients with acute heart failure (AHF). METHODS: Serial blood samples were collected from 84 AHF patients, divided etiologically into four groups: ischemic heart disease (IHD, n=26), valvular heart disease (VHD, n=17), dilated cardiomyopathy (DCM, n=25) and hypertensive heart disease (HHD, n=16). Serial venous blood concentrations of cTnI were measured immediately upon admission and at the time of symptom remission. According to the cTnI concentration on admission, patients were divided into two groups: cTnI(+) group (n=14) and cTnI(-) group (n=70). According to cTnI concentration of admission and symptom remission, patients were divided into group of cTnI(+) at admission and at symptom remission, group of cTnI(+) at admission but cTnI(-) at symptom remission, and group of cTnI(-) at admission and at symptom remission. The time of symptom remission, rehospitalization frequency and mortality 1, 3, 6 and 12 months after discharge were recorded. RESULTS: Compared with those in DCM and HHD groups, cTnI concentrations of IHD group on admission and at symptom remission increased significantly (P<0.01, P<0.05, respectively). The cTnI concentrations during symptom remission decreased in IHD, VHD and HHD groups compared with those on admission (P<0.05, P<0.01, P<0.05, respectively). The time of symptom remission in cTnI(+) group was longer than in cTnI(-) group (P<0.01) and the concentration of cTnI on admission was positively related to the time of symptom remission (r=0.286, P<0.01). The in-hospital mortality of cTnI(+) group was higher than in cTnI(-) group (P<0.05). The discharge mortality of cTnI(+) group was significantly higher than in cTnI(-) group in 12 months (P<0.01). Total cardiac deaths in cTnI(+) group including in-hospital and 12 months after discharge were higher than those in cTnI(-) group (P<0.01). Re-hospitalization frequency of 1, 3, 6 and 12 months after discharge in cTnI(+) group was significantly higher than in cTnI(-) group (P<0.05, P<0.01, P<0.01, P<0.01, respectively). Total cardiac deaths including in-hospital and 12 months after discharge in group of cTnI(+) at admission and at symptom remission were significantly higher than those in group of cTnI(+) at admission but cTnI(-) at symptom remission and in group of cTnI(-) at admission and at symptom remission (all P<0.01). CONCLUSION: The changes before and after treatment and level of cardiac troponin I(cTnI) in patients with acute heart tailure (AHF) are related to prognosis and etiology.