[Appraisal of the status of metabolism in myocardial layers in acute left-ventricular insufficiency using data from radionuclide examination methods]. / Otsenka sostoianiia metabolizma v sloiakh miokarda pri ostroi levozheludochkovoi nedostatochnosti po dannym radionuklidnykh metodov issledovaniia.

Experiments were conducted on 35 mongrel dogs. It was demonstrated in series I experiments that exclusion of a 14.5% myocardial area from the heart mass induces acute left-ventricular insufficiency manifested by authentic decrease of the cardiac ejection and left-ventricular output index and a 22% increase of pressure in the left atrium and pulmonary artery. The left-ventricular coronary blood flow and the blood flow in the myocardial layers of the right and left ventricles and in the interventricular septum increased significantly as compared to the control values. Distal to the area of the necrosis, however, the layer-by-layer flow of the blood in the left ventricle had a marked tendency to increase. In series II experiments, in myocardial necrosis the volume load, which was equal to one half and one initial circulation volume, mobilized the heart contractile activity, which led to increase of the coronary blood flow which was less than the initial level in series I experiments. Analysis of layer-by-layer blood flow after a volume load equal to one initial circulation volume showed it to be markedly increased in all layers of the left-ventricular anterior wall above and below the necrotic area, in the left-ventricular posterior wall, in the interventricular septum, and in the right-ventricular anterior wall. The increase of 201Tl-chloride accumulation in the myocardial layers under the studied conditions is evidently linked with activation of metabolic processes responsible for increase of heart contractile activity and, consequently, for increased uptake of 201Tl from circulation by the intact cardiomyocytes rather than with change in redistribution of the blood flow and its increase.

[The blood flow and catecholamine content in different layers of the myocardium in acute left-ventricular failure]. / Krovotok i soderzhanie katekholaminov v raznykh sloiakh miokarda pri ostroi levozheludochkovoi nedostatochnosti.

Four series of acute experiments were conducted on 28 male and female mongrel dogs under general anesthesia and artificial lung ventilation. Each dog weighed 12.5 kg. The catecholamine (CA) concentration and regional blood flow in myocardial layers (RBFML) of the left ventricle of the heart (LV) and in the transmural layer of the right ventricular anterior wall, the values of central hemodynamics, and the general coronary blood flow were determined. During a volume load the RBFML increased by more than twice, the CA content also grew, and there was mainly an increase in the concentration and seizure of adrenaline (A) in the intramyocardial and subendocardial layers of the LV anterior and posterior walls. The noradrenaline (NA) concentration reduced 3 times as compared to the control values. In acute left-ventricular insufficiency (ALI) the RBFML increased significantly in the left-ventricular subepi- and subendocardial layers. The NA and CA concentration reduced significantly in the LV anterior wall and increased significantly in the posterior wall as compared to the control values. The A concentration practically did not change in the LV anterior wall but increased significantly in the posterior wall as compared to the control values. Dosed volume load in ALI led to significant increase of the RBFML in the LV anterior and posterior walls as compared to the values during ALI in the controls. The CA concentration was increased significantly in the myocardial layers of the LV anterior and posterior walls, but it was much higher in the myocardium of the posterior wall than in the myocardium of the anterior wall.(ABSTRACT TRUNCATED AT 250 WORDS)

[An assessment of the reserve potentials of the heart by using volume loading with the exclusion of a portion of the left ventricular myocardium from contraction]. / Otsenka rezernykh vozmozhnostei serdtsa s pomoshch'iu ob''emnoi nagruzki na fone vykliucheniia chasti miokarda levogo zheludochka iz sokrashcheniia.

The reserve possibilities of the heart in dosed exclusion of part of the contractile myocardium of the left ventricle were determined by the initial functional condition of the "intact" myocardium. Overexertion by volume in exclusion of part of the myocardium from contraction is dangerous due to exhaustion of the myocardial contractility reserve, relative diminution of coronary circulation with the gradual increase of exertion and overloading of the lesser circulation, which are a secondary cause of the reduction of the reserve possibilities of the heart.

[Experimental validation of a method for the early diagnosis of the infection of vascular prostheses using 99m-TC-labelled leukocytes]. / Eksperimental'noe obosnovanie metoda rannei diagnostiki infitsirovanniia sosudistykh protezov s pomoshch'iu leikotsitov, mechennykh 99mTc.

Experiments on 9 dogs were staged for a study of a method of early diagnosis of infectivity of vascular prostheses of the abdominal aorta with the help of 99m-Tc-labelled leukocytes. A sterile synthetic vascular prosthesis was used for prosthetics of the abdominal aorta in the 1st control group of animals, a prosthesis, previously infected with St. aureus, was used in the 2nd group, a sterile prosthesis with its subsequent infecting by i.v. injection of St. aureus was used in the 3rd group. The role of antibiotic therapy in infectivity of vascular prostheses was studied on the animals of the 3rd group. A radionuclide study with autologous 99m-Tc-labelled leukocytes was conducted using the Deina-2 camera (Picker). Visualization of the prostheses was unobserved in the 1st control group; in the 2nd group the accumulation of 99m-Tc-leukocytes in the zone of the prosthesis and its visualization on the 4th-5th min. were noted; in the 3rd group the prosthesis was visualized on the 10th-15th min. After antibiotic therapy in the 3rd group visualization of the prosthesis was undetectable. The proposed method permitted visualization of a zone of infection in the early postoperative period, observation of the time course of infection development, and assessment of the efficacy of antibiotic therapy.