Using TEE to Evaluate the Effect of Levosimendan on Patients With ARDS Associated With RVD During MV

Acute respiratory distress syndrome (ARDS) is often complicated by right ventricular dysfunction (RVD), Acute cor pulmonale is the most serious form of ARDS complicated with RVD.Levosimendan is indicated for short-term treatment of acute decompensated heart failure that is not responding well to conventional therapy and requires increased myocardial contractile force.In 2016, the European Society of Cardiology issued recommendations for the management of acute right heart failure, stating that levosimendan can improve right ventriculo-pulmonary artery coupling by both increasing right heart contractility and reducing pulmonary vascular resistance.However, the clinical application of levosimendan in the treatment of ARDS right heart dysfunction is insufficient.Therefore, this study intends to use transesophageal ultrasound to evaluate right ventricular function, reduce the limitation of poor right ventricular window in transthoracic echocardiography, and conduct a multi-center randomized controlled study to further explore the effects of levosimendan on right ventricular function in ARDS patients, such as tricuspid ring systolic displacement (TAPSE) and tricuspid ring systolic displacement velocity (S '). Effects of right ventricular area change fraction (RV FAC), right ventricular end-diastolic area/left ventricular end-diastolic area (RVEDA/LVEDA), pulmonary circulation resistance (PVR), hemodynamics and mortality.

Acute respiratory distress syndrome (ARDS) is often complicated by right ventricular dysfunction (RVD),the incidence can be as high as 64%, Acute cor pulmonale is the most serious form of ARDS complicated with RVD. The prognosis of ARDS patients with RVD is worse and the risk of death would be significantly increased.Currently, there are very limited clinical drug treatment options for RVD.Levosimendan is indicated for short-term treatment of acute decompensated heart failure that is not responding well to conventional therapy and requires increased myocardial contractile force.In 2016, the European Society of Cardiology issued recommendations for the management of acute right heart failure, stating that levosimendan can improve right ventriculo-pulmonary artery coupling by both increasing right heart contractility and reducing pulmonary vascular resistance. Levosimendan is therefore recommended to be given priority over dobutamine in the treatment of acute right heart failure.At present, there are also relevant clinical studies reporting that levosimendan can be used in acute right heart failure caused by different causes, including a single center randomized controlled study reporting that levosimendan can do work in the right ventricle of patients with sepsis ARDS, and has beneficial hemodynamic effects.However, the clinical application of levosimendan in the treatment of ARDS right heart dysfunction is insufficient.Therefore, this study intends to use transesophageal ultrasound to evaluate right ventricular function, reduce the limitation of poor right ventricular window in transthoracic echocardiography, and conduct a multi-center randomized controlled study to further explore the effects of levosimendan on right ventricular function in ARDS patients, such as tricuspid ring systolic displacement (TAPSE) and tricuspid ring systolic displacement velocity (S '). Effects of right ventricular area change fraction (RV FAC), right ventricular end-diastolic area/left ventricular end-diastolic area (RVEDA/LVEDA), pulmonary circulation resistance (PVR), RV-PA coupling, hemodynamics and mortality.

Eligibility Criteria:
Inclusion Criteria:

* Patients who agree to participate in this clinical trial and sign informed consent
* Age 18-80 years old, gender unlimited
* Patients with ARDS(According to the diagnostic criteria of ARDS in Berlin 2012) requiring mechanical ventilation; Acute right ventricular dysfunction due to ARDS

Exclusion Criteria:

* Pregnant or lactating women;
* Chronic cardiac insufficiency, pulmonary hypertension and/or right ventricular enlargement caused by chronic cardiopulmonary disease, cardiogenic shock or after major cardiac surgery before ARDS;
* right ventricular myocardial infarction;
* Uncorrected hypotension, hypoxemia and hypercapnia, or acid-base balance disturbance
* Mechanical ventilation driving pressure \>=18cmH2O before randomization
* Rapid arrhythmia;
* pericardial tamponade;
* Pulmonary embolism;
* severe renal insufficiency;
* severe liver insufficiency;
* Failure to sign informed consent;
* known allergy to the test drug and control drug;
* Patients who have participated in other clinical trials within 30 days