Background/objectives: To evaluate whether biomarkers reflecting pathophysiological pathways and selected single nucleotide polymorphisms differ between patients (pts) with heart failure (HF).Methods: 110 pts with were involved, including HF pts with preserved ejection fraction (HFpEF, n=51) with hypertensive origin, HF pts with reduced ejection fraction (HFrEF) with ischemic aetiology (ICM) (n=32) and HFrEF with dilated cardiomyopathy (DCM) (n=27). We assessed selected HF biomarkers, echocardiographic examinations and functional polymorphisms selected from six candidate genes: CYP27B1, NOS3, IL-6, TGF beta, TNF alpha, and PPAR gamma. Results: Higher concentrations of TNF alpha were observed in pts with hypertensive HFpEF compared to pts with DCM (p=0.008). Pts with HFpEF had higher concentrations of TGF beta 1 compared to DCM and ICM (p=0.0001 and p=0.0003, respectively). For the NOS3 -786 C/T rs2070744 polymorphism in DCM there were significantly more CT heterozygotes than in ICM and HFpEF. In multivariate analysis TGF beta 1 (p=0.001) and syndecan 4 (p=0.001) were the only factors distinguishing HFrEF pts with DCM vs HFpEF and also TGF beta 1 (p=0.001) and syndecan 4 (p=0.023) were the only factors distinguishing HFrEF pts with ICM vs HFpEF pts.Conclusions: Inflammation mediated through TNF alpha and TGF beta 1 may represent an important component of an inflammatory response that partially drives the pathophysiology of HFpEF. NOS3 -786 C/T rs2070744 polymorphism in DCM may serve as a marker for more rapid progression of heart failure. The only biomarkers independently distinguishing HFpEF and HFrEF are syndecan 4 and TGF beta 1.