Assessing Venous Congestion in Acute and Chronic Heart Failure: A Review of Splanchnic, Cardiac and Pulmonary Ultrasound: Part 1: Conventional B-Mode, Colordoppler, and Vexus Protocol

Background and Objectives: Heart failure (HF) causes systemic and regional hemodynamic alterations that extend beyond the heart, profoundly affecting splanchnic circulation. Venous congestion in the hepatic and portal systems is a key but often underrecognized determinant of organ dysfunction and symptom burden. Conventional ultrasound and Doppler techniques offer a non-invasive, dynamic evaluation of these changes, potentially complementing standard echocardiographic and biomarker assessments. Materials and Methods: A systematic review was performed in PubMed, Embase, and the Cochrane Library up to July 2025, following PRISMA 2020 guidelines. Eligible studies included adult human investigations evaluating splanchnic vascular changes in HF using B-mode, color Doppler, or pulsed Doppler ultrasonography. Exclusion criteria were pediatric, animal, or non-English studies and non-standard imaging methods. Data on ultrasonographic parameters, hemodynamic correlations, and prognostic value were extracted and qualitatively synthesized; sympathetic nervous system; heart failure with preserved ejection fraction; ultrasound; b-mode, colordoppler, pulsed doppler. Results: A total of 148 eligible studies (n ≈ 7,000 patients) demonstrated consistent associations between HF severity and alterations in splanchnic flow. Findings included increased bowel wall thickness, portal vein dilation with elevated pulsatility, and monophasic or reversed hepatic vein waveforms, all correlating with higher right atrial pressure and adverse clinical outcomes. The integration of these parameters into the Venous Excess Ultrasound (VExUS) framework enhanced detection of systemic venous congestion. Conclusions: Conventional ultrasound assessment of splanchnic vasculature provides valuable, reproducible insight into systemic congestion in HF. Incorporating hepatic and portal Doppler indices into standard evaluation protocols may improve risk stratification, optimize decongestion therapy, and guide management. Further prospective validation is warranted to standardize cutoff values and define prognostic thresholds.