The goal of this prospective observational study is to evaluate whether right ventricular (RV) function parameters assessed via transthoracic echocardiography (TTE) can predict weaning success in adult intensive care unit (ICU) patients who are mechanically ventilated. The main questions it aims to answer are:

Can the TAPSE (Tricuspid Annular Plane Systolic Excursion) value predict successful extubation?

Do other right heart parameters (tricuspid S', RV-FAC, right atrial area, pulmonary valve acceleration time) provide additional prognostic value for weaning outcomes?

Participants will:

Be adult ICU patients planned for weaning from mechanical ventilation.

Undergo transthoracic echocardiography within 2 hours after meeting clinical weaning criteria.

Have the following echocardiographic parameters measured: TAPSE, tricuspid S', RV-FAC, right atrial area, and pulmonary valve acceleration time.

Be monitored for 24 hours after extubation to assess weaning success (defined as no need for reintubation, non-invasive ventilation, or high-flow oxygen support).

This is a prospective, observational, single-center study designed to investigate whether transthoracic echocardiographic (TTE) assessment of right ventricular function can predict weaning success in mechanically ventilated adult ICU patients. The primary objective is to determine the prognostic value of TAPSE (Tricuspid Annular Plane Systolic Excursion) in forecasting successful extubation.

Secondary objectives include the evaluation of additional echocardiographic parameters such as tricuspid annular systolic velocity (S'), right ventricular fractional area change (RV-FAC), right atrial area, and pulmonary valve acceleration time (PVAT). These parameters will be measured via bedside TTE within 2 hours after patients meet clinical weaning criteria and are hemodynamically stable.

All participants will be monitored for 24 hours after extubation. Weaning success is defined as the ability to sustain spontaneous breathing without the need for reintubation, non-invasive ventilation, or high-flow oxygen therapy during this period.

Data collection will include:

Echocardiographic measurements: TAPSE, tricuspid S', RV-FAC, right atrial area, and PVAT.

Demographic and clinical data: age, sex, BMI, ICU admission diagnosis, APACHE II and SOFA scores, ventilation settings, and duration of mechanical ventilation.

Post-extubation follow-up: reintubation, non-invasive ventilation or high-flow oxygen use, SpO₂ values, blood gas analysis, and vital signs.

This study does not involve any interventions beyond standard care. Echocardiography is routinely performed in ICU settings and poses no additional risk to participants.

The results may support the integration of right heart function assessment into routine ICU weaning protocols and improve clinical decision-making by reducing the incidence of weaning failure and associated complications.

Inclusion Criteria:

• Receiving invasive mechanical ventilation in the ICU
• Planned extubation (weaning) according to standard clinical criteria
• Hemodynamically stable at the time of transthoracic echocardiography (TTE)
• Ability to undergo echocardiographic assessment within 2 hours prior to extubation
• Informed consent obtained from patient or legal representative

Exclusion Criteria:

• Known severe tricuspid valve disease or congenital heart disease
• Moderate to severe pericardial effusion or cardiac tamponade
• Inadequate acoustic window for transthoracic echocardiography
• Patients requiring urgent or unplanned extubation
• Use of extracorporeal life support (e.g., ECMO) at the time of assessment
• Known pulmonary embolism or acute cor pulmonale
• Pregnancy

Adult patients who are receiving invasive mechanical ventilation in the intensive care unit (ICU) and are scheduled for planned extubation based on standard clinical weaning criteria. All participants must be hemodynamically stable and able to undergo transthoracic echocardiographic assessment prior to extubation.