Primary percutaneous coronary intervention (PPCI) of the occlussion or significant stenosis of infarct artery is a method of choice in treatment of acute myocardial infarction with ST segment elevation (STEMI). It is not clear, what is the optimal management of patients with acute myocardial infarction with ST elevations (STEMI) treated by primary percutaneous coronary intervention (PPCI) who have at least one significant stenosis of non-culprit coronary artery. Numerous cardiology centers perform staged PCI on significant stenoses involving the "non-infarct" coronary artery (arteries) 3-40 days after PPCI, but the benefit of this staged PCI for such patients has not yet been clearly demonstrated.