Abstract Background In the current era, there is always search for better cardiovascular biomarkers to early diagnose the disease. Objectives We aimed to investigate the association between a novel biomarker, cardiothropin-1 (CT-1), and standard markers of myocardial ischemia in patients with acute coronary syndrome (ACS) in Turkey. Patients and Methods In this prospective cohort study, patients who were admitted to our institution between July 2012 and July 2013 with the diagnosis of ACS were included. The standard markers of myocardial necrosis and CT-1 were evaluated at the time of admission and after 6 hours. Changes in laboratory parameters were statistically tested and correlated with routinely used markers of myocardial ischemia. The distribution of the data was analyzed by the Kolmogorov-Smirnov test. Proportional analysis and changes in laboratory parameters were evaluated with Chi-Square test and Fisher Exact test. Statistical significance was defined as p<0.05. Results The study enrolled 24 patients (14 male, 10 female) with ST-segment elevation myocardial infarction (STEMI) and 16 patients (9 male, 7 female) with non-ST-segment elevation myocardial infarction (NSTEMI) with elevated cardiac enzymes such as creatine kinase (CK), creatine kinase-MB (CK-MB) and Troponin-T (Tn-T). The average age of the patients was 61.45 ± 11.04 years. Increasing CT-1 levels were correlated with the increasing CK (p=0.035 and p=0.018, respectively), CK-MB (p=0.006 and p=0.096, respectively), and Tn-T (p=0.041 and p=0.000, respectively) at first and at the 6th hour measurements. The CT-1 values were found to be more increased in the STEMI group (p=0.0074). Conclusion CT-1 is one of the novel biomarkers for cardiac injury. It is correlated with standard markers of myocardial ischemia and the results suggest that CT-1 can be used as a new biomarker.