Abstract only Introduction: Cardiac troponin (cTn) measurements play a pivotal role in diagnosing and managing myocardial infarction (MI). Nonetheless, to prevent unnecessary expenditure, it is essential to optimize the usage of cTn testing. The AHA guidelines underscore the importance of minimizing low-value care, considering the widespread prevalence and substantial expenses related to cardiovascular disease. Hence, our study hypothesis is that expert-recommended cTn testing could effectively decrease unnecessary testing requests. Aims: This study aims to contrast the frequency of normal and of serial cTn I test results within a General University Hospital (GUH) setting and a specialized Cardiology University Hospital (CUH). Methods: Our cross-sectional study encompassed all cTn I tests performed at both GUH and CUH between November 2022 and March 2023. We excluded patients receiving postoperative care following invasive cardiac procedures and those engaged in research protocols. We categorized the study population by sex and age (<60 or ≥60 years), as well as by whether the cTn I test was serially conducted (≥2 times within 24 hours). A serial cTn I test, as recommended by the 4th Universal definition of MI to detect any rise and/or fall, was considered a correct request. We utilized the chi-square test for categorical variables and the Mann-Whitney test for continuous data, setting a 5% significance level. Normal reference levels were <16 and <34 ng/L for women and men, respectively. Results: The study incorporated a total of 5,360 tests performed in GUH, with 46.2% on women and 60.9% on individuals aged ≥60 years. In CUH, 8,487 tests were conducted, with 42.0% on women and 53.8% on individuals aged ≥60 years. GUH displayed a higher proportion of normal cTn I test results compared to CUH (70% versus 45%, p < 0.0001) and a lower percentage of serial cTn I tests (40.3% versus 53.4%, p < 0.0001). Moreover, GUH demonstrated a lower median troponin value of 8 (2.5-33.8) versus 37 (7-455) in CUH, p < 0.0001. Conclusions: The increased prevalence of normal cTn I results and the lower frequency of serial cTn I tests in GUH indicate potential economic inefficiencies related to excessive cTn I testing requests. Expert intervention could help in avoiding unnecessary cTnI test requests.