[A method of studying characteristics during modeling of blood flow in stenosed vessels].

A new method of visualization employed in experimental hydrodynamics, namely a method of photochromic visualization (PCV), was used to examine the fluid flow in a tube with a diaphragm. The PCV is based on the design of colour markers in a model physiological solution exposed to laser radiation for 10(-6) to 10(-9) s. For the model flow in a tube with transitory Re numbers both qualitative and quantitative data were obtained.

[Functional state of the hemostatic system in the early periods after artificial heart implantation in calves].

The functional state of hemostasis in the early periods after implantation of an artificial heart was studied in experiments on calves. The importance of studying the initial indices of the hemostasis system in calves both for selection of the animals and for determination of the tactics of conducting the experiment was shown. Preliminary drug management of the animals for the purpose of creating optimum functional correction of the coagulation and anticoagulation systems may have a marked positive effect.

[Correlation of atrial and ventricular contractility. The possibility of using the atria for controlling the artificial heart].

A possibility of the artificial ventricle regulation using information on the atrial contraction is discussed. Correlations between atrial wall tension and ventricle tension as well as the pressure under radom heart rhythm variations were studied. The wall tension of the appropriate heart portion was recorded by the arched tensiometers, and intraventricular pressure under cavity catheterization by the electric manometer.

[Contractile reaction of the myocardium of patients with heart diseases to chemical scarification of cell membranes].

Strips of the myocardium from the auricula atria of patients suffering from mitral stenosis (MS) and septal defects of the heart (SDH) removed during the operation were treated with ethylenediaminetetraacetic acid (DETA)--3mM--to increase the cell membrane permeability (scarification). The mechanical response of the contractile proteins to the change in the Ca2+ was recorded in the ethylene-hexaaminetetraacetic acid (EHTA)--3mM--against the background of increased membrane permeability to the Ca-EHTA complex permitting to regulate Ca2+ concentration in myofibrillae from 10(-9) to 10(-4)M. As shown, with the same threshold concentrations (5.

[Method of bench testing an artificial heart].

A procedure for bench trials of the artificial heart (AH), that comes to determining the relationship between the AH performance and the duration of the systole with constant pressure differentials at the in- and outlets of the AH and pulse rate. The results of the AH trials by the proposed procedure are described.

[Effect of adrenaline on the contractility of different portions of the myocardium of homeotherms].

The contractility of myocardial strips from the atrium and ventricle of rabbit heart had some differences in the parameters of single contraction, interval--tension relationship, and transitional process. These differences were eliminated by increasing the concentration of epinephrine in bath solution. Epinephrine changed the mode of time--force relation of contraction and induced appearance of extremum in all the parts of the heart.

[New construction of an orthotopic heart prosthesis made of fluorosiloxane rubber].

A new design of orthopedic heart prosthesis with artificial ventricles of the saccular type -- model (see text) is described and results of its test-trials are reported. All the components of the heart prosthesis are made of fluorosiloxan rubber.