This study is a prospective, multicenter, single-arm clinical trial conducted in China to evaluate the efficacy and safety of a novel left ventricular assist device, SynFlow Duro system, manufactured by ForQaly Medical in the treatment of post cardiotomy cardiogenic shock.

This study is a prospective, single-arm clinical trial to be conducted in at least 2 centers in China to evaluate the efficacy an safety of a novel micro-axial flow pump for left ventricular assistance in post cardiotomy cardiogenic shock. The trial population includes those who fail to wean from cardiopulmonary bypass OR have refractory cardiogenic shock after cardiac surgery. Patients with right heart failure will be excluded. Eligible subjects will receive SynFlow system for bridging to cardiac recovery or durable cardiac therapy (cardiac transplantation or implantation of approved Ventricular Assist Device). The primary endpoint is device support success, defined as survival to 30 days post-explant or hospital discharge (whichever is longer) OR to explantation in case of bridging to durable cardiac therapies.

Inclusion Criteria:

• 18≤Age≤80, any sex.
• Failure to wean from CPB or refractory cardiogenic shock after cardiac surgery.

Failure to wean from CPB is defined as failed to discontinue CPB or post-weaning CI <2.2L/min/m2 + PCWP >15mmHg, despite optimal pre-weaning management and receiving at least one high dose inotrope.

Refractory cardiogenic shock is defined as a condition that occurs despite adequate fluid status and meets all the following criteria:

① CI<2.2L/min/m2 + PCWP>15mmHg despite receiving at least one high dose inotrope or IABP; OR SBP <80mmHg or MAP<50mmHg despite receiving at least one high dose intrope + high dose norepinephrine or IABP.

② Presence of at least one signs indicating hypoperfusion: decreased mentation; cold, clammy, ashen or cyanotic extremities or skin or livedo reticularis; urine output<30ml/h or 0.5ml/kg/h; or lactate>2mmol/L or metabolic acidosis.

- Patient has signed the informed consent form.

Exclusion Criteria:

• Body surface area>2.5m2.
• Presence of any cardiac assist device (other than an IABP).
• Right ventricular failure.
• Evidence of any vascular disease or anatomy precluding placement or deployment of the device (e.g. severely calcified vessel).
• Evidence of ventricular thrombus.
• Moderate or severe aortic valve insufficiency/stenosis, or severe aortic valve calcification.
• Presence of mechanical aortic valve or cardiac contractile device.
• Obstructive, hypertrophic cardiomyopathy.
• Presence of uncorrected ventricular septal defect, atrial septal defect or patent foramen ovale.
• Mechanical manifestation of AMI (e.g. ventricular septal rupture, papillary muscle rupture, ventricular rupture).
• Any hematological disorder causing fragility of blood vessel or hemolysis.
• Known allergy or intolerant to heparin.
• Presence or suspicion of active systemic infection.
• Cardiopulmonary resuscitative maneuver lasting longer than 20 minutes before device placement.
• Sustained or non-sustained ventricular tachycardia or ventricular fibrillation unresponsive to medical therapy.
• Severe hepatic dysfunction, renal failure or severe respiratory failure
• Pregnant or lactating female.
• Concomitant enrollment in another investigational drug or device study where the primary endpoint has not yet been completed or that will clinically interfere with the endpoint of this investigation.
• Other conditions considered unsuitable for participating in this investigation by the investigators.