Prospective Validation of the Venous Excess Ultrasound “(VExUS)” Score

Abstract Venous congestion is an under-recognized contributor to mortality in critically ill patients. Unfortunately, venous congestion is difficult to measure, and right heart catheterization (RHC) remains the gold standard. Recently, a novel “Venous Excess Ultrasound (VExUS)” score was developed to noninvasively quantify venous congestion using inferior vena cava (IVC) diameter and doppler flow through the hepatic, portal, and renal veins. A preliminary retrospective study of post-cardiac surgery patients showed promising results, including a high positive-likelihood ratio of high VExUS grade for acute kidney injury. However, further validation studies have not been reported in broader patient populations, and validity of VExUS as compared to other measures of venous congestion such as IVC diameter is unknown. To address this gap, the authors prospectively validated the VExUS against right atrial pressure (RAP), with comparison to inferior vena cava (IVC) diameter. Patients undergoing RHC at the Denver Health Medical Center underwent VExUS examination before their procedure. VExUS grades were assigned before RHC, blinding ultrasonographers to RHC outcomes. After controlling for age, sex, and common comorbidities, there was a significant positive linear association between RAP and VExUS grade (p < 0.001, R 2 = .68). VExUS had a favorable AUC for prediction of a RAP ≥ 12 mmHg (0.99, 95% CI 0.96-1) compared to IVC diameter (0.79, 95% CI 0.65–0.92). These results suggest a strong physiologic correlation between VExUS and RAP in a diverse patient population, and support future studies of VExUS as a tool to assess venous congestion and guide management in a variety of critical illnesses.