## 4 Discussion  
In this single-center cohort study of patients hospitalized with AHF, the quantification of venous congestion at admission using the VExUS protocol showed no significant differences between those with HfpEF and those with HfrEF. Contrary to our initial hypothesis, this suggests that the VExUS score may serve as a reliable tool for assessing systemic congestion across the full spectrum of heart failure phenotypes. These findings are aligned with recent evidence highlighting the utility of multimodal congestion assessment irrespective of LVEF and support the broader clinical applicability of the VExUS protocol. The baseline characteristics of our cohort mirrored those reported in national and international HF registries [24], with a predominance of HfpEF patients. Atrial fibrillation and anticoagulation therapy were more frequent in this group, in agreement with previous studies [24; 25; 26]. CKD was more prevalent in the HfrEF group, despite being typically associated with HfpEF [26]. Severe valvular disease and implantable cardioverter-defibrillators were also more common in HfrEF, reflecting the advanced structural damage characteristic of this phenotype and its specific therapeutic indications [27]. Regarding the degree of congestion assessed by physical examination, no significant differences were found between groups; however, tissue edema appeared more frequently in patients with reduced ejection fraction (HfrEF). This group also showed a higher prevalence of pleural effusion and ascites, likely reflecting volume overload-driven decompensation--typical of HfrEF--even though a mixed mechanism involving both vascular redistribution and volume expansion is increasingly recognized [28]. [PERSON] et al. [29] reported similar findings, noting that both the preserved (HfpEF) and reduced ejection fraction groups showed comparable levels of venous congestion in acute heart failure, despite the higher natriuretic peptide levels seen in HfrEF patients. Consistently, our study found increased levels of both intravascular (NT-proBNP) and tissue congestion markers (CA125) in HfrEF patients. However, recent studies have reported elevated CA125 levels in HfpEF patients compared to controls, suggesting a potential role for CA125 as a marker of congestion and prognosis in HfpEF [30; 31]. The discrepancies between our findings and those of these studies may be attributed to differences in sample size, patient characteristics, or methodological approaches. These variations underscore the complexity of heart failure phenotyping and the need for further research to clarify the role of CA125 in HfpEF. Additionally, VExUS, as a direct ultrasound-based tool for assessing venous congestion, may provide complementary information to biomarker profiles, potentially enhancing our understanding of congestion pathways in HfpEF and HfrEF. A recent meta-analysis by [PERSON] et al. [32] emphasized the high prevalence of clinical and ultrasound signs of congestion across the heart failure spectrum, highlighting the importance of a multimodal approach to improve risk stratification. Our findings align with this conclusion, showing no differences in sonographic congestion patterns, which reinforces its value in tailoring therapy. While physical signs of congestion were similarly distributed, pleural effusion and ascites were significantly more frequent in HfrEF, consistent with its greater volume overload tendency [28]. Nonetheless, no differences were observed in VExUS grading, supporting the findings from [PERSON] et al. [29] and a recent meta-analysis by [PERSON] et al. [32], which emphasized the high prevalence and prognostic value of congestion markers regardless of LVEF. Our data reinforce these conclusions and advocate for VExUS as a complementary tool in bedside evaluation. Although some subgroup analyses, such as that of [PERSON] et al. [33], suggest that VExUS-based congestion grading is independent of LVEF, further dedicated studies are needed--underscoring the relevance and future direction of our work.