Abstract Objective Recent studies have demonstrated associations of either abnormal liver function tests (LFT) or liver stiffness (LS) increase with negative outcomes in decompensated heart failure (DHF). We aimed to assess incidence, clinical and prognostic relevance of combined increase of LS and LFT in DHF. Methods The study included 130 patients (73% male, 68±11 years [M±SD], myocardial infarction 49%, atrial fibrillation 63%, diabetes mellitus 39%, chronic kidney disease 24%, EF 39±14%, EF<40% 54%, NT-proBNP 3601 [1905; 6220] pg/ml, alcohol abuse 26.2%) hospitalized with DHF, in whom levels of alanine transaminase (ALT), aspartate transaminase (AST) and total bilirubin (TB) and LS (using transient elastography) were assessed in the first 48 hours of admission. Patients with previous liver disease or acute hepatitis were excluded. Higher then upper normal limit levels of either AST/ ALT/ TB were considered as LFT increase; LS >5.9 kPa – as abnormal. Outcomes were assessed by phone contacts in 1, 3, 6 and 12 months. Kruskal–Wallis test, Pearson's chi-squared test and Kaplan-Meier survival analysis were used. P<0.05 was considered significant. Results Median LS was 11.1 (6.8; 24.5) kPa, median ALT 20.1 (14.9; 30.7) U/l, AST 26 (20; 36.3) U/l, TB 19 (13.2; 27) μmol/l. LS and ALT, AST, TB increase occurred in 79.2 and 15.4, 13.1, 40.8% patients. Based on combination of LS and LFT increase subjects were divided into 3 groups: without LS and LFT increase (G1, 16.2%), with only LS increase (G2, 33.1%) and both LS and LFT increase (G3, 46.1%). Isolated LFT increase was noted only in 6 (4.6%) patients. G3 compared to G2 and G1 was characterized by lower EF (33±14 vs 41±13 and 45±11%, p<0.001) and inferior vena cava (IVC) collapsibility (23.3 vs 41.9 and 61.9%, p=0.003), higher IVC diameter (2.4 [2; 2.6] vs 2.2 [2; 2.4] and 2 [1.95; 2.2] cm, p<0.001), right ventricular diameter (3.5 [3.2; 3.9] vs 3.2 [3; 3.6] and 3 [2.9; 3.1] cm, p<0.001), pulmonary artery pressure (56 [45; 66] vs 50 [37; 65] and 40 [33; 49] mmHg, p=0.014), higher rate of tricuspid regurgitation (70 vs 44.2 and 28.6%, p=0.001). Groups did not differ by alcohol abuse rate (p=0.152). Kaplan–Meier analysis of groups for all-cause death probability showed significant differences (figure): event-free survival for G3 vs G1 and G2 was 64.9 vs 81 and 95% (log rank p=0.011, χ2=6.5 for G3 vs G1; log rank p=0.081, χ2=3.1 for G3 vs G2). HF readmission probability was significantly higher in G3 vs G2 and G1: corresponding event-free survival was 50.9 vs 66.7 and 80% (log rank p=0.012, χ2=6.3 for G3 vs G1; log rank p=0.036, χ2=4.4 for G3 vs G2). Conclusions Combination of abnormal LFT and increased LS was observed in 46.1% of DHF patients and was associated with lower EF, more serious right-sided dysfunction and higher probability of negative long-term outcomes.