According to the ischemic cascade theory, the myocardial ischemia is a sequence of pathogenetic processes leading to an irreversible lesion - necrosis and scarring of the myocardium. Its timely and accurate diagnostics is significant for lethality risk stratification, arrhythmic events and chronic heart failure (CHF). The article provides clinical examples of the myocardial infarction and post-infarction cardio sclerosis of various localizations, as well as its complications — aneurisms and thrombosis. The parameters of global systolic function of the left-ventricular are assessed depending on the size of scar zone, approaches to using the magnetic resonance tomography (MRT) are describes, which help to solve clinical tasks in patients with ischemic heart disease.