Objective To evaluate the clinical improvements after autologous bone marrow mononuclear cells (BMMNCs) percutaneously injected into coronary artery in patients with heart failure due to non-ischemic cardiomyopathy using PET myocardial peffusion/metabolic imaging.Methods From February 2011 to October 2012,40 patients with heart failure due to non-ischemic cardiomyopathy were selected.The test group including 15 patients (13 males,2 females,average age (57.5±14.5) years) received the autologous BMMNCs intracoronary injection on the basis of drug treatment.The other 25 cases (21 males,4 females,average age (58.0±12.0) years) were taken as the control group and only received the drug treatment.All patients were followed up for 24 months,and the myocardial perfusion/metabolism imaging,echocardiography,brain natriuretic peptide (BNP) test,6-minute walking experiment were performed.The data were analyzed by two-sample t test.Results During the follow-up period,the test group had no ventricular arrhythmia and other serious complications,and the patients' symptoms had been improved.There was no change in myocardial perfusion after treatment of autologous BMMNCs,but the myocardial metabolic defect by volume reduced from (43.79± 17.99) cm3 to (28.19±9.27) cm3 (t =3.33,P＜0.01) 24 months after the treatment.The myocardial metabolic defect by volume at the baseline and after 24 months in the control group was (43.30±15.70) cm3,(48.51±15.77) cm3 respectively (t=1.01,P＞0.05).In the test group,the left ventricular end-diastolic diameter decreased from (64.0±8.0) mm to (59.0±7.0) mm 24 months after the treatment (t=2.04,P＜0.05),and the left ventricular ejection fraction was significantly higher than that before treatment:(45.0±4.0) ％ vs (27.0±6.0) ％ (t =10.81,P＜0.01).Conclusion PET myocardial perfusion/metabolic imaging can be used as tools in evaluating the therapeutic effect of autologous BMMNCs in patients with heart failure due to non-ischemic cardiomyopathy.