Incorporating the Venous Excess Ultrasound Score (VExUS Score) Into Contemporary Haemodynamic Risk Assessment in Pulmonary Arterial Hypertension: The INVEXUS-PAH Study

Pulmonary arterial hypertension (PAH) is a progressive disorder characterised by increased pulmonary vascular resistance, right ventricular overload, systemic venous congestion, and high mortality. The ESC/ERS 2022 simplified four-strata model (low, intermediate-low, intermediate-high, high risk) guides treatment decisions using WHO functional class, 6-minute walk distance, and BNP/NT-proBNP levels. However, biochemical markers may be costly or insufficiently sensitive to early haemodynamic deterioration. VEXUS (Venous Excess Ultrasound Score), a point-of-care ultrasonographic method assessing hepatic, portal, and renal venous Doppler patterns, has shown promise in representing venous congestion. This study evaluates whether VEXUS correlates with ESC/ERS risk categories and invasive haemodynamic parameters including right atrial pressure, mean pulmonary arterial pressure, pulmonary vascular resistance, cardiac output, and pulmonary output. The study further aims to explore whether integrating VEXUS into PAH follow-up may strengthen risk assessment.