Prognostic Role of Copeptin, H-FABP, and TTE in Pulmonary Embolism in the Emergency Department

Pulmonary embolism (PE) remains a major diagnostic and prognostic challenge in emergency departments due to its heterogeneous clinical presentation and potentially high mortality. Although echocardiography and conventional cardiac biomarkers are commonly used in clinical practice, the additional prognostic value of novel biomarkers such as copeptin and heart-type fatty acid-binding protein (H-FABP) requires further investigation.

This exploratory prospective study (March 2021-September 2022) included adult patients (≥ 18 years) diagnosed with acute PE confirmed by radiological imaging in the emergency department. Patients with chronic/unconfirmed PE, incomplete data, or those referred from external centers were excluded. The primary analysis compared survivors and nonsurvivors at 30 days to evaluate the prognostic value of copeptin, H-FABP, and echocardiographic parameters. Transthoracic echocardiography (TTE) was performed after diagnosis to assess right heart function and pulmonary artery pressure (PAP), right ventricular/left ventricular ratio (RV/LV), right and left ventricular end-diastolic diameters (RV-EDD and LV-EDD), and tricuspid annular plane systolic excursion (TAPSE). Biomarkers (troponin, pro-BNP, D-dimer, copeptin, and H-FABP) were analyzed using standard laboratory assays and enzyme-linked immunosorbent assay (ELISA). The primary outcome was 30-day mortality.

A total of 88 patients were analyzed. Although H-FABP and copeptin levels were higher in nonsurvivors, these differences were not statistically significant for predicting 30-day mortality. Echocardiographic parameters-particularly PAP, RV-EDD, and RV/LV-were significantly associated with the severity of right ventricular dysfunction and clinical outcomes (p < 0.05). In multivariable logistic regression analysis copeptin, H-FABP, PESI score, ICU admission, RV-EDD, and LV-EDD remained independently associated with 30-day mortality. Cut-off values were determined by ROC analysis using the Youden index.

Although biomarkers were not significant as continuous variables, exploratory categorized analysis based on cut-off values suggested a potential association with mortality. Rapid bedside echocardiography combined with appropriate biomarker testing may improve risk stratification in patients with PE in emergency settings, while larger studies are needed to clarify the role of these biomarkers.