The Effectiveness and Safety of Levosimendan in Patients With Severe Aortic Stenosis and Heart Failure Undergoing Transcatheter Aortic Valve Replacement

Inclusion Criteria:

1. Signed (by the subjects or their legally acceptable representatives) informed consentdocument indicating that they understand the purpose of and procedures required forthe study and are willing to participate in the study

2. Severe aortic stenosis

3. Mean transaortic gradient ≥ 40 mmHg(at rest or stress)

4. Aortic peak velocity ≥ 4m/s;

5. Arotic valve area <0.8 cm2 and/or aortic valve area index< 0.5cm2/m2

6. Cardiac dysfunction

7. LVEF≤50% (estimated by Simpson)

8. NT-proBNP≥1500ng/L；

9. Symptoms of dyspnea and fatigue when at rest or after slight exertion (New YorkHeart Association ≥ Ⅲ -Ⅳ)

10. Intermittant fluid retention and/or symptoms induced by low cardiac output atrest, but lack of hemodynamic instability

Exclusion Criteria:

1. Decompensated acute cardiac failure due to hemodynamic instability

2. A historty of torsade de points ventricular tachycardia

3. Known allergic reaction or sensitivity to Levosimendan or excipients

4. Received levosimendan within 1 week prior to the planned clinical trial

5. Serum potassium < 3.5 mmol/L and > 5.5 mmol/L before the drug study

6. Systolic blood pressure < 90mmHg at baseline

7. Estimated glomerular filtration rate (eGFR) ≤30 mL/min/1.73m2.

8. Unable to participate in study for being critically ill asssed by clinicians

9. Other concomitant severe morbidities leading to poor prognosis and decreasedmortality, such as malignant tumor and disease involving other vital organs; lifeexpectancy less than 1 year.