Diagnostic Accuracy of Hepatic Vein SFF Compared With TAPSE for Assessment of RV Systolic Function in Mechanically Ventilated Patients

• Diagnostic accuracy of hepatic vein systolic filling fraction compared with TAPSE for assessment of right ventricular systolic function in mechanically ventilated critically ill patients (Diagnostic test): 1\. Point-of-Care Echocardiography Protocol Echocardiograms were recorded within the first 24 hours of ICU admission using an echocardiograph by two intensivists who were experienced in echocardiography (more than 7 years of experience) and will be blinded to the study. Electrocardiograms were recorded continuously during the echocardiographic examination. Images will be saved for offline analysis. The ultrasound machine will be equipped with a phased-array transducer. Right Ventricular Assessment: From the apical 4-chamber view, the M-mode cursor will be aligned with the lateral aspect of the tricuspid valve annulus to measure the Tricuspid Annular Plane Systolic Excursion (TAPSE). To ensure accuracy and account for beat-to-beat variability, the final TAPSE value recorded for each patient will be the average of measurements taken over three consecutive cardiac cycles. Right ventricular systolic dysfunction (RVSD) is strictly defined as an average TAPSE of < 16 mm (7).

Primary outcomes

• Hepatic vein systolic filling fraction (SFF) and Tricuspid Annular Plane Systolic Excursion (TAPSE) [within the first 24 hours]: Hepatic vein systolic filling fraction (SFF) will be measured using colour Doppler ultrasonography of the hepatic vein. Examinations will be performed within a 5-minute window of transthoracic echocardiography and obtained at end-expiration to minimise the effects of respiratory variation. All patients will be mechanically ventilated, and positive end-expiratory pressure (PEEP) and plateau pressure will be recorded at the time of assessment. Unit: Percentage (%) Right ventricular systolic function will be assessed by measuring tricuspid annular plane systolic excursion (TAPSE) using transthoracic echocardiography at the bedside. Echocardiographic examination will be performed within a 5-minute window of hepatic vein Doppler assessment and obtained at end-expiration to minimise respiratory variation. All patients will be mechanically ventilated, and positive end-expiratory pressure (PEEP) and plateau pressure will be recorded at the time of assessment. Unit: Millimetres mm

Secondary outcomes

• Baseline Demographic and Clinical Data, Synchronized Hemodynamic and Respiratory Data, Total length of ICU stay (days) and ICU mortality and the correlation and agreement between the hepatic vein and RV systolic function via TAPSE. [till 28 days after admission]: To determine the correlation and agreement between the hepatic vein SFF and right ventricular (RV) systolic function Unit of Measure Correlation coefficient (Pearson's r or Spearman's ρ), quantitatively assessed via Tricuspid Annular Plane Systolic Excursion (TAPSE) at the bedside. Tricuspid Annular Plane Systolic Excursion (TAPSE) should be < 16 mm. SFF cut-off of ≤ 54.5% for predicting RV dysfunction measured by Agreement statistic (e.g., Cohen's kappa or intraclass correlation coefficient) and diagnostic accuracy measures (sensitivity, specificity, area under the receiver operating characteristic curve) . Base line demographic data (wt in kg , height in meter, sex), clinical, laboratory characteristics off all patients and the Sequential Organ Failure Assessment (SOFA) Score by points and the Acute Physiology and Chronic Health Evaluation (APACHE) score by score. Total duration of invasive mechanical ventilation in days. Intensive Care Unit (ICU) length of stay in days.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

1. Age ≥ 18 years.
2. Mechanically ventilated patients
3. Patients in whom transthoracic echocardiography (TTE) can be performed Adequate acoustic window to measure TAPSE.
4. Patients in whom hepatic vein Doppler assessment is feasible Adequate subcostal view for Doppler sampling.

Exclusion Criteria: