Patient clinical characteristics (n=123) Autologous bone marrow mononuclear cell transplantation in patients with acute myocardial infarction and chronic heart failure in Latvia I.Briede2, E.Sokolova2, I.Narbute2, I.Kumsars2, D.Sondore2, K.Trusinskis2, S.Jegere2, G.Latkovskis2, A.Dombrovskis2, K.Dombrovska2, A.Rudzitis2, K.Strenge2, K.Spalva2, R.Mikijanskis3, E.Jakobsons1, L.Patetko1, S.Krapse1, B.Rupaine1, K.Erglis1, M. Erglis1, A.Erglis1. Heart failure and acute myocardial infarction are the leading cause of morbidity and mortality. In recent years, the rapid advancements in stem cell research have garnered to novel therapies in reversing myocardial injuries and improving left ventricle ejection fraction. Purpose Results Evaluate whether regenerative therapy is safe and improves cardiac systolic function within one year in patients with acute coronary syndrome and chronic heart failure. Clinical follow-up at three months reached n=101 (82.1%). One year follow-up reached n=88 (71.54%). MACE in AMI group (n=70) at 12 months: Non-Q MI, n=2 (%); Cardiac death, n=1 (%); TLR, n=4 (%); TVR, n=5 (%); ST, n=2 (%). Matherials and methods p<0.001 p<0.001 Between September 2009 and April 2016 patients aged 18 to 75 years with acute myocardial infarction and successful revascularization (but with reduced LV EF 15-50% or LV apical aneurysm) or known heart failure at the Latvian Center of Cardiology were enrolled for autologous mononuclear stem cell transplantation (n=123). There were n=100 (81.3%) patients with acute myocardial infarction and n=23 (18.7%) patients with chronic heart failure. During follow-up, we analysed clinical and angiographic results such as all-cause death, cardiac death, target vessel-related myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR). We report the interim analysis of the follow-up at 3 month and 12 months after stem cell therapy. Statistical data analysis was performed with SPSS software (IBM SPSS Statistics Version 21, SPSS inc., USA). Patient clinical characteristics (n=123) Acute myocardial infarction (AMI) n = 100 (81.3%) Chronic heart disease n = 23 (18.7%) Male gender n = 112 (91.9%) Dyslipidemia n = 90 (73.2%) Diabetes mellitus n = 9 (7.3%) Positive family history n = 39 (31.7%) Smoking n = 49 (39.8%) Previous PCI n = 33 (26.8%) Stem cell implantation artery LAD = 105 (85.4%) LCX = 3 (2.4%) RCA = 15 (12.2%) Mean cell amount implanted 47.4 ± 26.1 million Mean baseline LVEF in AMI n=100, % 42.76 ± 9.02 Mean baseline LVEF in CHF n=23, % 43.2 ± 8.6 p=0.005 p=0.015 Conclusions Stem cell therapy is safe and significantly improves cardiac systolic function within three months and one year in patients with acute coronary syndrome and chronic heart failure. The study should be continued with longer follow-up up to 24 months in a larger group of patients. Funding: This study was supported in part by Latvian National Research Program "Biomedicine for Public Health" (BIOMEDICINE) and by grant from corporation „Sistemu Inovacijas” 1 Cell Transplantation Centre, Pauls Stradins Clinical University Hospital 2 Pauls Stradins Clinical University Hospital 3 Neurosurgery clinic, Pauls Stradins Clinical University Hospital