Patients with anterior wall AMI treated by PCI will undergo, after successful revascularization of the infarct artery, measurement of the left ventricular pressure, and femoral angiogram. Patients with elevated LV pressure and adequate femoral access will be randomized to standard pharmacological treatment of AMI vs. mechanical unloading by Impella-CP (on top of the standard treatment) for 36-48 hours. LV unloading will be guided by measurement of PCWP by Swan-Ganz catheter. On the day 4-7, and at 3 months after the AMI, the patients will undergo SPECT and 3D-echocardiography to assess ventricular remodeling and extent of the post-infarct scar. The patients will be followed for at least 12 months for the occurrence of heart failure and adverse cardiovascular events. The study will test the hypothesis, whether the LV mechanical unloading after PCI will attenuate post-infarct scar and cardiac remodeling.

1. Eligible patients with be screened before PCI
2. The patients with undergo coronary angiography and PCI according to common medical practice
3. At the end of the PCI procedure, after a successful revascularization, a pigtail catheter will be used to measure LV filling pressure and to perform femoral angiography (to evaluate femoral access).
4. Patients fulfilling angiographic and hemodynamic criteria will be randomized 1:1 to standard care vs. mechanical unloading by Impella-CP.
5. The patients will be treated on a CCU with experience with use of Impella-CP.
6. On the CCU, all patients will be monitored by a Swan-Ganz catheter for 48 hours.
7. The pump speed will be adjusted to maintain the lowest tolerated PCWP while avoiding suction events.
8. Mechanical unloading will last 36-48h. Afterwards, the Impella-CP will be explanted.
9. All patients will receive standard pharmacotherapy of AMI, according to the guidelines.
10. Revascularization of significant non-infarct lesions will be performed during the index hospitalization.
11. 3D-echocardiography and Tc-SPECT (D-SPECT) will be performed on the day 5-7 of the index hospitalization. LV phasic volumes and extent of nonperfused myocardium (scar) will be evaluated automatically, using software provided by the vendor.
12. 3D-echocardiography and Tc-SPECT will be repeated at 3 months after the AMI.
13. The patients will be followed by out-patient check-ups every 12 months.

Inclusion Criteria:

• large anterior wall AMI with estimated ischemia of <24h
• at risk of the beginning of cardiogenic shock (SCAI A/B)
• blood pressure <160/100 mmHg
• no previous IM based on the patient's history
• no previously known LV systolic dysfunction
• assumed new LV dysfunction documented by ECHO or LVG (LVEF < 45%)
• infarct culprit lesion at the proximal LAD, LMCA or equivalent, with TIMI <= 2 flow
• LV end-diastolic pressure of >= 18 mmHg measured invasively

Exclusion Criteria:

• history of chronic LV dysfunction
• chronic anticoagulation therapy
• the need of IIb/IIIa blockers at the PCI
• inadequate femoral vein access (peripheral artery disease)
• significant valve disease or valve prosthesis
• CPR >5 min before PCI
• LV thrombus
• periprocedural AMI (obliteration of large non-culprit artery during PCI)