Abstract Background Congestion is the main reason for hospital admission in patients with acute heart failure (AHF). Lung ultrasound (LUS) examination has been proposed as a simple, accurate, and available tool to assess pulmonary congestion, adding significant prognostic insights to clinical examination. Aim This is a multicentre retrospective study aiming to investigate the prognostic value accuracy of B-lines, compared with B-type natriuretic peptide (BNP) and clinical congestion both at admission and at discharge in a large cohort of patients admitted for AHF divided according to ejection fraction cut-off in HFrEF, HFmrEF and HFpEF). Methods We analysed the merged data of four cohorts hospitalized for AHF. All patients underwent clinical assessment, echocardiography evaluation, BNP measurement and LUS measurements in 8 or 28 chest zones. The primary outcome was the composite endpoint of all-cause mortality and/or HF re-hospitalization at 60 and 180 days. Results A total of 551 patients (264HFrEF, 100 HFmrEF and 187 HFpEF) were included. Median age was 77 [69–82] and 337 patients were men. Dividing our population according to HF classifications, we found that admission BNP levels were significantly higher in HFrEF compared to HFmrEF and HFpEF (p=0.002). No significant differences in terms of admission B-lines count were found among groups (p=0.80). ROC Curve analysis showed the significant prognostic power (p<0.05) of clinical congestion score, BNP and B-lines at admission. These findings were confirmed also for the same variables at discharge (p<0.05). Univariate analysis confirmed as predictor of poor prognosis admission congestion score≥2 (HR: 4.12 [2.84–5.99]; p<0.001), admission B-lines>30 (HR: 1.43 [1.02–1.99]; p=0.035), tricuspid anular plane systolic excursion (TAPSE) ≤16 mm (HR: 1.74 [1.25–2.42]; p=0.001), inferior cave vein (ICV) >21 mm (HR: 2.74 [1.80–4.18]; p<0.001) and E/e' ≥15 (HR: 1.71 [1.18–2.47]; p=0.005). Multivariable analysis demonstrated that admission B-lines were significantly related to poor prognosis only in HFrEF (p=0.025) and HFpEF (p=0.041), but not in HFmrEF (p=0.59). Considering the change from admission to discharge of congestion score, BNP and B-lines, the Δ B-lines during hospitalization remains the only significant predictor of poor prognosis (≥60days) across HF spectrum (HFrEF, HFmrEF and HFpEF; p≤0.001). Conclusions Although both clinical congestion signs and B-lines were predictors of all-cause mortality and HF rehospitalization at 180 days, the changes of these variables during hospitalization were the stronger predictor of poor outcome. In particular, an inadequate B-lines in-hospital reduction (Δ B-lines <9), was significant associated to increased risk for adverse event in all HF subtypes. Current study confirm the relevance to apply a multiparametric congestion assessment in order to better stratify hospitalized AHF patients. Funding Acknowledgement Type of funding sources: None.