Background: Urocortin 1 (UCN1) has cardiostimulatory, vasodilatory, diuretic and natriuretic effects, and its expression increases in heart failure (HF).

Aim: To determine UCN1 levels in patients with HF, to evaluate UCN1's relationship with various clinical parameters, and to assess UCN1 as a diagnostic marker in HF, compared to pro-B-type natriuretic peptide (pro-BNP).

Methods: We investigated serum levels of UCN1 and pro-BNP in 90 consecutive patients with systolic HF (left ventricular ejection fraction [LVEF] ≤ 45%) and 90 healthy controls. Serum UCN1 and pro-BNP levels were measured using the ELISA method. Transthoracic echocardiography was performed to determine LVEF and pulmonary artery systolic pressure (PASP). Glomerular filtration rate (GFR) was estimated using the Cockcroft-Gault formula.

Results: UCN1 level was higher in HF patients (391.5 [357.0-482.0] pg/mL, p < 0.001). UCN1 was positively related with NYHA class (r = 0.89, p < 0.001), and PASP (r = 0.39, p < 0.001); and negatively related with LVEF (r = -0.46, p < 0.001), and GFR (r = -0.21, p = 0.046). A significant positive correlation was found between pro-BNP and UCN1 levels (p < 0.001, r = 0.96). Receiver operating characteristic (ROC) curves yielded an area under the curve (AUC) of 0.99 (95% CI 0.98-1.00,p < 0.001) for UCN1 and 1.00 (p < 0.001) for pro-BNP in the diagnosis of HF.

Conclusions: UCN1 increases with worsening HF and left ventricular dysfunction. It may be used as a diagnostic biomarker in systolic HF, but the incremental value of measuring UCN1 in patients tested for pro-BNP is questionable.