The purpose of this research study is to evaluate whether timely and aggressive temporary Mechanical Circulatory Support (tMCS) through the Impella 5.5® in patients with acute decompensated heart failure complicated by cardiogenic shock (ADHF-CS) has the potential to reduce the HF-CS related clinical events compared to the current standard of care.

To demonstrate the efficacy of timely temporary mechanical left ventricular unloading with the Impella 5.5® assist device in patients with acute decompensated heart failure complicated by cardiogenic shock (ADHF-CS) vs. current standard of (pharmacological) care

Inclusion Criteria:

1. Evidence of HFrEF according to ESC HF guidelines (LVEF ≤ 35%) 2. Signs of (persistent) congestion (elevated CVP, edema, rales, ascites, pleural effusion) 3. Evidence of CS with presence of at least 2 of the 3 following:

1. Hypotension

   1. systolic blood pressure <90 mmHg for at least 30 min OR
   2. mean arterial pressure <60 mmHg for at least 30 min

2. Hypoperfusion

   1. lactate > 2.0 mmol/L (two consecutive values > 2 mmol/L with at least 30 min between samples, with non-decreasing trend on if on (steady doses of) inotropes and/or vasopressors)
   2. amino-L-transferase >200 U/L (two consecutive values > 200 Ul/L with at least 30 min between samples, with non-decreasing trend if on (steady doses of) inotropes and/or vasopressors)
   3. creatinine rise ≥ 0.3 mg/dl/24h ( 26,53 μmol/L)
   4. oliguria (≤ 0,5 ml/kg/h, ≤ 720 ml/24 h)

3. Inotropes/vasoactives (use of)

Exclusion Criteria:

1. Contraindications for Impella 5.5
2. Severe concomitant RV failure
3. Grade IV mitral regurgitation eligible for surgical treatment
4. Dialysis for end-stage renal failure
5. Acute coronary syndrome (type 1, AMI)
6. Bradycardia and AV blocks necessitating pacemaker implantation
7. HD parameters and biochemistry alterations as specifically defined for SCAI CS E
8. Combined cardiorespiratory failure
9. Resuscitated (OHCA/PEA)
10. History of CVA or TIA within previous 90 days
11. History of acute myocardial infarction within previous 30 days
12. History of bleeding diathesis or known coagulopathy (including heparin-induced thrombo-cytopenia), any recent GU or GI bleed, or will refuse blood transfusions
13. Inflammatory
14. Active systemic infections
15. Acute myocarditis