The purpose of this prospective, multicenter, randomized controlled clinical trial is to evaluate the effectiveness of the transcatheter left ventricular assist system (Ventiflow LP) in providing circulatory support to patients during high-risk PCI procedures compared to veno-arterial extracorporeal membrane oxygenation (VA-ECMO).The participants will be randomly assigned to the experimental group or the control group after enrollment, and will undergo percutaneous coronary intervention(PCI) with support from Ventiflow LP or VA-ECMO respectively. All participants need to undergo a 3-month follow-up after operative.

Inclusion Criteria:

1. 18 Years to 90 Years

2. The cardiac team determined that the subject needs coronary artery revascularization, but there is a higher risk of CABG, or the subject refuses to accept CABG. After comprehensive evaluation by the cardiac team, it was determined that the subjects could benefit from PCI

3. The subject is diagnosed with acute or chronic coronary syndrome, and

   1. LVEF≤ 35% or
   2. LVEF ≤ 40% and NYHA Classification is III or IV

4. Informed consent

5. The participant meets all the above clinical inclusion criteria and must comply with at least one of the following imaging criteria.

1. At least two coronary artery CTOs (diameter of occluded artery ≥ 2.5mm) 2. Unprotected left main coronary artery disease, and meeting one or more complex operating standards 3. Three-vessel disease and meeting two or more complex operating standards

Complex operations are defined as:

1. Bifurcation lesions require treatment of dual branches (including stents and PTCA)
2. Calcification lesions require complex operation or instrument assistance (Excimer laser coronary atherectomy, intravascular lithotripsy, or rotational atherectomy)
3. Severe distortion requires complex operations
4. The target lesion is CTO (diameter of occluded artery ≥ 2.5mm and J-CTO score ≥ 2 )

Exclusion Criteria:

1. Acute ST-elevation myocardial infarction within 7 days or receiving thrombolytic therapy;
2. Cardiopulmonary resuscitation within 24 hours;
3. Patients who have had cardiogenic shock (systolic blood pressure < 90 mmHg for more than 30 minutes or need catecholamines to maintain systolic blood pressure above 90 mmHg) or hemodynamic instability within 7 days before surgery;
4. Atrial or ventricular septal defect (including post-infarct VSD), left ventricular wall thrombus; left ventricular rupture, cardiac tamponade, or concomitant cardiopulmonary failure;
5. Presence of aortic stenosis/calcification (aortic orifice area ≤ 0.6cm2), documented moderate to severe aortic regurgitation (echocardiographic assessment grade ≥2+); have an artificial aortic valve;
6. Severe pulmonary hypertension, right heart failure or severe tricuspid regurgitation;
7. Prior or current use of a persistent left ventricular assist device (LVAD), or use of IABP, extracorporeal membrane oxygenation (ECMO), or percutaneous ventricular assist device (such as Impella or Tandem Heart) within 7 days prior to surgery;
8. History of stroke or transient ischemic attack within 1 month before surgery;
9. Patients with renal failure (creatinine ≥3 times ULN) and may require dialysis treatment;
10. Subject has abnormal liver function (elevated aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin levels ≥3 times ULN);
11. Moderate and severe anemia (hemoglobin <90g/L); Subject has abnormalities in coagulation parameters that cannot be corrected (defined as platelet count ≤ 75×109/L or INR ≥2.0 or fibrinogen ≤1.50g/l); or inability to be treated with antiplatelet agents and anticoagulants;
12. Active visceral hemorrhage within 1 month;
13. History of allergy to heparin, contrast media, etc.;
14. Aortic abnormalities that preclude surgery, including aneurysms, extreme curvature, or calcification; or known severe arterial disease that precludes the trial, such as aortic dissection, Marfan syndrome, etc.;
15. Severe peripheral arterial obstructive disease (stent, tortuosity, stenosis, dissection, etc.) that prevents study device placement;
16. Infection at the site of the planned surgical puncture site or suspected active systemic infection with fever or need for antibiotic therapy;
17. Pregnant women and lactating women;
18. The subject has participated in other medical device clinical trials/drug clinical trials during the same period;
19. ECMO cannot be implanted or there are contraindications to its application and any other conditions that the investigator considers inappropriate to participate in this trial.