The aim of the paper is to study the mononitrate effect on regional systolic function of left ventricle (LV) in patients with myocardial infarction (MI). A total of 48 pts with MI were investigated 3–4 months after beginning of the disease by method of radionuclide ventriculography. Hemodynamic parameters were evaluated in acute pharmacological test (isosorbide mononitrate, 40 mg). This drug usage led to increase of ejection fraction (by 12 %) and decrease of end-systolic volume (by 14 %). Study of regional LV systolic function showed significant increase of regional ejection fraction and peak ejection rate in area under lession (by 35–50 %), but these did not achieve physiological levels of defined parameters. Obtained results show favourable effect of mononitrate on regional hemodynamics in pts with MI. Possible mechanisms of this effect are discussed.