Adherence to Clinical Practice Guidelines for Non-ST Elevation Acute Coronary Syndrome in the Emergency Department: Exploring the Role of Social, Healthcare-system, and Clinical Determinants

OBJECTIVES: The aim of this study was to assess adherence to the European Society of Cardiology 2020 non-ST elevation acute coronary syndrome (NST-ACS) guidelines, identify factors affecting this compliance, and explore the link between adherence and adverse cardiac outcomes. METHODS: This prospective cohort study was conducted in a tertiary-level academic hospital between January 2022 and January 2023. Patients diagnosed with NST-ACS in the emergency department (ED) were included. The primary outcome measured was the rate of adherence to the guidelines, and secondary outcomes were factors affecting this adherence in the ED and its association with 28-day adverse cardiac outcomes. RESULTS: Of the 298 patients included, guideline adherence was achieved in 32.2% in the ED. The highest compliance was observed in performing a 12-lead electrocardiogram (ECG) within 10 minutes (99.7%), while the lowest was found for obtaining additional right and posterior ECG leads when ongoing ischemia was suspected (42.3%). Factors associated with better adherence included the experience level of the treating physician, the presence of cardiac-quality chest pain, initial ischemic ECG findings, higher initial troponin levels, and advanced history, electrocardiogram, age, risk factors, and troponin score and Charlson comorbidity index. Complete guideline adherence over 28 days was achieved in 19.1% of patients and was found to be significantly associated with lower rates of adverse cardiac outcomes. CONCLUSIONS: Adherence to NST-ACS guidelines was generally low but was associated with improved patient outcomes. This study highlighted the importance of various factors associated with guideline adherence. Future research should explore further barriers to guideline adherence and develop targeted interventions.