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

Can the Left Ventricular Outflow Tract Velocity Time Integral (LVOT VTI) predict successful extubation?

What is the prognostic value of other echocardiographic measures such as Mitral Annular Plane Systolic Excursion (MAPSE), E/e' ratio, E/A ratio, Mitral Deceleration Time (MDT), and Myocardial Performance Index (Tei index) in forecasting weaning outcomes?

Participants will:

Be adults receiving mechanical ventilation and scheduled for weaning

Undergo transthoracic echocardiography (TTE) within 2 hours after meeting weaning criteria

Have the following parameters measured: LVOT VTI, MAPSE, E/e', E/A, MDT, and Tei index

Be monitored for 24 hours post-extubation to determine if they remain off ventilatory support, including reintubation, non-invasive ventilation, or high-flow oxygen therapy

This study aims to provide a comprehensive understanding of how systolic, diastolic, and global cardiac functions influence extubation success, potentially improving ICU decision-making and reducing complications, length of stay, and healthcare costs.

This prospective, single-center observational study aims to assess the predictive value of left ventricular function parameters obtained via transthoracic echocardiography (TTE) in determining weaning success in mechanically ventilated adult ICU patients.

Following fulfillment of weaning criteria, patients will undergo TTE evaluation within 2 hours. The echocardiographic assessment will include the measurement of:

Left Ventricular Outflow Tract Velocity Time Integral (LVOT VTI)

Mitral Annular Plane Systolic Excursion (MAPSE)

E/e' ratio

E/A ratio

Mitral Deceleration Time (MDT)

Myocardial Performance Index (Tei index)

These measurements aim to reflect systolic, diastolic, and global left ventricular functions. After the echocardiographic assessment, patients will be followed for 24 hours to determine weaning success, defined as the ability to maintain spontaneous breathing without reintubation, non-invasive ventilation, or high-flow oxygen support.

By integrating non-invasive, bedside cardiac function assessments into the extubation decision-making process, the study seeks to contribute to more physiologically guided weaning strategies. The results may help reduce weaning-related complications and optimize resource use in critical care settings

Inclusion Criteria:

• Currently receiving mechanical ventilation in the ICU
• Planned extubation after meeting standard weaning criteria
• Hemodynamically stable at the time of echocardiographic evaluation
• Written informed consent obtained from the patient or legally authorized representative

Exclusion Criteria:

• Surgery within the previous 24 hours
• Presence of significant valvular heart disease or known cardiomyopathy
• Inadequate acoustic window for transthoracic echocardiography
• Ongoing use of extracorporeal support (e.g., ECMO)
• Patients with Do-Not-Resuscitate (DNR) orders or expected to die within 24 hours
• Re-intubation planned prophylactically regardless of clinical status
• Pregnant patients

The study population will consist of adult patients admitted to the intensive care unit (ICU) who are receiving invasive mechanical ventilation and are scheduled for extubation after fulfilling standard weaning criteria. All participants will be hemodynamically stable at the time of echocardiographic assessment. Patients with significant structural heart disease, inadequate echocardiographic imaging windows, or ongoing extracorporeal support will be excluded. The population represents a typical critically ill cohort undergoing weaning from mechanical ventilation.