The study will compare clinical outcomes between complete revascularization during hospitalization for ST elevation myocardial infarction (STEMI) and intervention after 30 days and intervention based on outpatient non-invasive ischemia testing in patients with multivessel coronary artery disease (MVD) presenting with first ever ST elevation myocardial infarction.

This study is prospective, randomized, multicentre, open label study in patients with ST elevation myocardial infarction (STEMI) with multivessel coronary artery disease (MVD) defined as >70% stenosis in a non-culprit vessel, initially treated with culprit only primary PCI. The patients will be enrolled in four high volume PCI centers after successful culprit only primary PCI and then randomly assigned to one of three treatment arms:1. complete revascularization of all non-culprit significant lesions in a single session during initial hospitalization; 2. same revascularization in a single session after 30 days; 3.revascularization or it's deferral based on ischemia testing using Dobutamin stress echocardiography. The study will explore differences in occurrence of major adverse cardio-cerebral events (cardiac death, repeated myocardial infarction, cerebrovascular accident and repeated revascularization) and complications of interventions during 12 months follow-up.

Inclusion Criteria:

• Clinical and electrocardiographic signs of first ever ST elevation myocardial infarction (chest pain lasting less than 12 hours with persistent ST elevation of ≥ 1mm in two contiguous leads on ECG recording)
• Multivessel coronary artery disease (MVD) on initial coronary angiogram, defined as visually assessed stenosis of more than 70% of any of the non-culprit vessels
• Treated with primary PCI of infarct related artery (IRA) only.

Exclusion Criteria:

• Hemodynamically unstable patients defined as presence of cardiogenic shock, intraaortic balloon pump (IABP) implantation and mechanical ventilation prior, during and after primary PCI;
• Presence of significant valvular disease;
• Decision that patient needs to be treated with coronary artery bypass graft (CABG) and/or valvular replacement or reconstruction surgery after initial culprit only PCI;
• Myocardial infarction is caused by stent thrombosis:
• Chronic total occlusion of any of the coronary arteries on initial angiogram;
• Previously treated by CABG surgery;
• Estimated life expectancy less than one year.