[Peculiarities of myocardial remodeling in the acutest phase of experimental myocardial infarction in rats].

Features of early postischemic cardiac remodeling is well studied both in the clinic and in the experiment. However, the data for this process in the first 60 minutes after occlusion of the coronary vessel in the literature are absent practically. In experiments in rats in which acute myocardial ischemia was reproduced by the simultaneous ligation of the left coronary artery, with the help of echocardiography it is shown that in the first minutes of ischemia in left ventricular systolic function of the heart sharp drops: so, at the 20th minute of ejection fraction (EF) is reduced up 84.5 (79.3-89.2) to 51.7 (50.2-54.4)% - P < 0.05; fraction shortening (FS) is decreased up 52.6 (47.8-59 and 3) to 26.5 (25.9-28.1)% - P < 0.05; a end-systolic dimension (ESD) of the left ventricle is increased up 1.90 (1.70-2.26) to 3.80 (3.50-4.10) mm - P < 0.05, whereas the sham animals were not observed any statistically significant violations of left ventricular systolic function during the observation period (60 minutes). In the period up 20 to 60 min of ischemia is noted a gradual improvement of the relative systolic heart function. At the 60th minute of ischemia all recorded echocardiographic parameters were significantly (P < 0.05) different from those reported in the period from 10 to 20 min of ischemia - EF 62.4 (59.0-64.3)%, FS 33, 7 (31.1-35.2)%, ESD 3.10 (2.80-3.40) mm, etc. Analysis of the results suggests that noted in our experiments the maximum reduction in left ventricular ejection time coincides with the peak of arrhythmogenesis, i.e. with a maximum risk of sudden cardiac death.