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The presence of twisted helical flow patterns in the cardiac cavities during ventricular filling and ejection was supposed. This work was intended in order to show that the intraventricular trabeculation plays the determining role in such a flow formation and to find some analytical approaches for its analysis. The morphometric study of human left-ventricular and aortic corrosion casts and dynamic measurement of the aorta by MRI-technique were performed. The data were analysed by means of the "Mathematica'" program. Two groups of trabecules were identified that refer to the inlet and outlet of the ventricular blood flow. The first group consists of trabecules of the free left-ventricular wall. The second group consists of long trabecules going along the anterior left-ventricular wall and intracavital lines of the papillary muscles. Both are twisted clockwise and converge in the flow direction. Each group of trabecules is oriented towards the mitral or aortic valve orifices, correspondingly. It was concluded that the helical trabecular organization acts as flow directing paddles that change their mutual orientation during the cardiac cycle evolution. The reorientation of the flow takes place due to sequential contraction of the ventricular structures. The formalization of trabecular orientation will allow one to calculate improved models of implantable substitutes and auxiliary devices for cardio-vascular surgery.

Basic results are considered of aerohydrodynamic and thermophysical experiments, in which secondary tornado-like jets (TLJ) are revealed and investigated. These jets are self-organized under conditions of flow past surfaces with three-dimensional recesses (dimples) with a second-order curvilinear surface (TLJS – tornado-like jet surface). Exact solutions are given of unsteady-state Navier–Stokes and continuity equations, which describe the TLJ. The impact is considered, which is made on the flow in dimple by forces forming a flow of new type with built-in secondary tornado-like jets. These forces are absent in the case of flow past initially smooth surfaces. The problems are discussed of reducing the aerohydrodynamic drag on the TLJS, of enhancing the heat and mass transfer with the level of hydraulic loss lagging behind the degree of enhancement, of increasing the critical heat loads under conditions of boiling and supercritical flows of continuous medium past the TLJS, of preventing cavitation damage to the TLJS in hydraulic apparatuses, of reducing the adsorption of foreign matter on these surfaces, of reducing the friction between TLJS rubbing against one another, and of raising the efficiency of facilities for tornadolike conversion of energy of renewable low-potential sources. It is demonstrated that the obtained exact solutions of Navier–Stokes and continuity equations provide an adequate model of generation and evolution of swirling flow of blood in human blood circulation system, which enables one to proceed to development of safe and effective devices for substitution of organs in cardiac surgery. An inference is made about the universality of the flow of new type for raising the efficiency of technologies involving flows of various media.

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Biodegradable film compositions based on natural biopolymer gelatin with immobilized colchicine were prepared and their efficiency in prevention of the adhesion process in the pericardium was evaluated on rabbit model of postoperative pericarditis. The use of gelatin-based biodegradable film compositions significantly reduced the intensity of adhesion formation in the pericardial cavity, while immobilization of anti-inflammatory drug colchicine amplified their anti-adhesion activity.