VExUS aligns with invasive congestion pressure in acute heart failure and cardiogenic shock
Venous congestion is not just a bystander in acute heart failure and cardiogenic shock; it is part of the physiology that drives worsening organ function at the bedside. In this prospective single-center study of 94 patients admitted to a cardiac intensive care unit, the Venous Excess Ultrasound Score (VExUS) was tested against simultaneously measured right atrial pressure within 24 hours of admission. The central question was whether a bedside ultrasound congestion score could mirror the invasive hemodynamic burden that clinicians often use as a reference point when assessing filling pressures and systemic congestion. It did, but not perfectly.
High VExUS, defined as grades 2 to 3, was present in 29 patients, or 31% of the cohort. Across the full sample, VExUS correlated with right atrial pressure with a Spearman coefficient of 0.67, a relationship strong enough to support biologic coherence rather than casual overlap. The score also moved inversely with the MAP–RAP gradient, which fits the pathophysiology of venous hypertension compressing organ perfusion from the back end rather than simply reflecting low forward flow. In practical terms, a patient can have a blood pressure number that looks acceptable while the venous side of the circulation is already congested enough to impair organ drainage and perfusion.
The study also linked higher VExUS to impaired right ventricular function and to greater hepato-renal biochemical abnormalities. That pattern is clinically intuitive: when the right ventricle fails to empty effectively, venous pressure rises, the liver and kidneys become exposed to sustained congestion, and laboratory markers begin to drift away from normal. By contrast, lactate and urine output did not separate the groups, which is a useful reminder that early hemodynamic congestion and overt systemic hypoperfusion do not always appear together. A patient can be congested before lactate rises or urine output falls.
Discordance between RAP and VExUS exposed a second layer of risk
RAP–VExUS discordance appeared in 30.9% of patients. That finding matters because it shows the ultrasound score is not merely a surrogate for a single pressure reading; it may be capturing the downstream expression of venous congestion in tissues and organs. In a subset with elevated right atrial pressure above 10 mmHg, those who also had High VExUS carried worse hepato-renal biochemical dysfunction than patients with Low VExUS, with a statistically significant difference. The incremental value of VExUS beyond invasive RAP was seen most clearly for bilirubin, suggesting that ultrasound evidence of systemic venous congestion may help identify patients whose hepatic drainage is already suffering even when invasive pressure alone does not fully explain the biochemical picture.
This is an important physiologic distinction. Right atrial pressure gives a snapshot of pressure at one point in the circulation, while VExUS samples the venous consequences in the abdominal and systemic veins that feed the liver and kidneys. In congested patients, those organs do not respond only to mean arterial pressure or to cardiac output; they respond to the combination of impaired venous outflow, elevated backpressure, and reduced perfusion gradient. The data support a complementary role for ultrasound phenotyping alongside invasive hemodynamic assessment rather than a simple replacement strategy.
High VExUS did not show a statistically significant association with in-hospital mortality, although mortality was numerically higher in the High VExUS group at 24% versus 15%. The study was not powered to settle prognostic questions, so the absence of significance should not be interpreted as proof of no risk difference. A larger cohort would be needed to determine whether the score does more than mirror hemodynamics and biochemical congestion. For now, the signal is strongest in physiology, not outcomes.
Why the score may matter at the bedside
The appeal of VExUS in cardiac intensive care is its potential to translate venous congestion from an abstract pressure concept into something directly visible at the bedside. Right-sided failure, venous hypertension, and organ dysfunction often evolve together, but invasive catheter data are not always available, repeatable, or desirable in every patient. Ultrasound-based venous assessment offers a repeatable, noninvasive way to identify patients whose kidneys and liver may be under strain even when classical markers of shock remain equivocal. In a setting where treatment decisions often hinge on whether to intensify diuresis, escalate hemodynamic support, or accept ongoing congestion as part of the price of stabilization, that distinction has direct therapeutic consequences.
The cohort also reinforces the central role of the right ventricle in congestive physiology. Right ventricular impairment can amplify systemic venous pressure, worsen hepatic and renal congestion, and reduce the effective gradient for organ perfusion. VExUS seems to capture some of that downstream burden. The score therefore functions less like a standalone verdict and more like an additional lens on congestion phenotype, one that may be particularly useful when right atrial pressure alone does not tell the whole story.
The investigators worked in a prospective design at a single center, and all patients underwent measurements close to admission, which strengthens the physiologic timing of the observations. Still, the sample was modest, the analysis of mortality was exploratory, and the study cannot define treatment thresholds or prove that acting on VExUS improves outcomes. The most defensible reading is narrower and clinically grounded: in acute heart failure and cardiogenic shock, VExUS tracked invasive right atrial pressure and identified a subset with greater hepato-renal biochemical derangement, especially when RAP was already elevated. The remaining task is to determine whether that information changes management in a way that meaningfully alters recovery of organ function.