BACKGROUND Fibulin-1 and fibulin-5 are extracellular glycoproteins from the fibulin family. Both are expressed in the vessel wall and protect against vascular damage. AIMS We aimed to investigate whether fibulin-1 and-5 may be used to exclude non-ST-segment elevation myocardial infarction (NSTEMI) in the emergency setting. METHODS The study included 48 patients in the NSTEMI group and 42 controls who presented with chest pain of noncardiac origin as confirmed by a comprehensive evaluation including coronary angiography. Blood samples for fibulin-1, fibulin-5, and troponin I measurements were drawn on admission to the emergency department. RESULTS Demographic characteristics were similar in patients with NSTEMI and controls. The median levels of both glycoproteins were lower in patients with NSTEMI as compared with controls: fibulin-1, 96.9 µg/ml (interquartile range [IQR], 20-503 µg/ml) vs 111.5 (IQR, 71-457 µg/ml), P = 0.01, and fibulin-5, 38 ng/ml (IQR, 15-509 ng/ml vs 57 ng/ml (IQR, 26-631 ng/ml), P <0.001. The receiver operating characteristic curve analysis revealed the cutoff value of 105.6 µg/ml for fibulin-1 and of 49.4 ng/ml for fibulin-5 to exclude NSTEMI on admission. CONCLUSIONS The present study demonstrated that fibulin-1 and-5 measurements might be used to exclude NSTEMI in patients admitted to the emergency department with acute chest pain.