The primary purpose of this research protocol is to evaluate the relationship between the Venous Excess Ultrasound VExUS score a comprehensive point of care ultrasound method for assessing systemic venous congestion and echocardiographic measures of right heart structure and function in adult patients undergoing cardiac valvular surgery This prospective observational study arises from the knowledge that traditional means of evaluating congestion such as physical examination and isolated inferior vena cava IVC assessment are often subjective inconsistent and influenced by technical and physiologic variables As right ventricular RV function and venous congestion have broad implications for outcomes in cardiac surgery the study aims to provide a more objective and reliable correlation using an integrated ultrasound approach with the VExUS score

Rationale and Background

Venous congestion is a key determinant of morbidity following cardiac surgery frequently driven by RV dysfunction and assessment by standard right heart catheterization is invasive and not always feasible The VExUS score combining IVC hepatic vein portal vein and renal vein Doppler ultrasonography offers a realtime noninvasive alternative to gauge venous congestion with greater accuracy Understanding the precise relationship between VExUS and echocardiographic surrogates of RV function such as TAPSE tricuspid annular plane systolic excursion RV fractional area change FAC and RV systolic pressure RVSP can improve patient risk stratification fluid management and outcome prediction in perioperative care

The protocol specifically seeks to

Quantify the correlation between the grades and severity of each VExUS component hepatic portal and renal vein Doppler patterns and overall VExUS score against established echocardiographic parameters reflecting right heart dimensions like RV basal diameter RA area and function TAPSE RV FAC RV systolic pressure Identify which single VExUS component most strongly mirrors the severity and nature of right heart impairment Determine whether preoperative VExUS measurements offer incremental predictive value for perioperative morbidity including acute kidney injury liver dysfunction mechanical ventilation need ICU stay and mortality beyond established surgical risk scores such as EuroSCORE II and STS score

Study Hypothesis

The study hypothesizes that noninvasive assessment of systemic venous congestion using VExUS will demonstrate a strong positive correlation with echocardiographic parameters reflecting right ventricular function particularly with indices such as TAPSE and RV FAC It further posits that higher VExUS scores and severity grades will be associated with worse RV function on echocardiography and that this relationship will help guide management decisions and outcome prediction in the perioperative cardiac surgical population

By systematically exploring these relationships the study aims to validate the utility of VExUS scoring in the cardiac anesthesia critical care domain and guide best practices for fluid and congestion management of vulnerable patients undergoing complex valvular surgeries