19 research outputs found
Application of Tornado-flow Fundamental Hydro- dynamic Theory to the Study of Blood Flow in the Heart -Further Development of Tornado-like Jet Technology
ABSTRACT It has been proved previously that the Tornado-like swirling flows have strictly ordered hydrodynamic structure which can be exhaustively described by using the exact solution of non-stationary Navier-Stokes and continuity equations for this class of flows The current study proposes a method of measurement and calculation of the flow structural parameters derived from the exact solution, using LV cavity casts morphometry in humans and dogs and Multislice computed tomography (MSCT) of LV in two patients without severe cardiac pathology. It has been shown that the dynamic expression of intracardiac trabeculae and instant shape of LV cavity within a complete cardiac cycle correspond closely to the stages of single Tornado-like jet evolution. Since the intraventricular trabeculae profile is streamlined continuously by the blood flow, it should determine the hydrodynamic flow structure as an ensemble of guiding vanes. Therefore it has been concluded that the intraventricular flow dynamics can be analyzed and quantified using the exact solution. Application of this analysis to the MSCT visualization of LV cavity dynamics has shown the validity of this approach, which may be used for clinical diagnostic purpose. A realistic mathematical model of intraventricular blood flow has been proposed and evaluated. The results showed a good agreement between the model and known cardiac anatomy and function
Analysis of structure of intraventricular blood flow based on studies of architectonics of trabecular layer in left ventricle
Aims
To overcome numerous contradictions in the knowledge of the blood transportation, a hypothesis was supposed asserting the swirling pattern of blood flow in the heart and main vessels which resembles tornado-like flows and which is widespread in nature. These flows can be exhaustively described by the exact solutions of the nonstationary hydrodynamic Navier-Stokes equations and the continuity equations for the class of viscous swirling flows offered by Kiknadze - Krasnov.
Materials and methods
Using morphometric studies of human and canine left ventricular casts and Multislice Computed Tomography it has been shown that the trabeculae in the ventricular cavity are oriented along the streamlines of the tornado-like flow of appropriate dimension. Moreover, this principle covers both the diastolic trabeculae of the inlet part of the left ventricle and the systolic trabeculae of the outlet part of the left ventricle.
Results
It is concluded that the main trabeculae function consists in the structural organization of the intraventricular tornado-like swirling flow of Kiknadze – Krasnov type.
Conclusion
The hydrodynamic analysis of the blood flow laws is indispensable for the development of new diagnostics criteria in cardiology, cardiac surgery optimization, the design of new implantable and paracorporal devices contacting with blood flow and mathematical and physical modeling of circulation
Our new tornado-compatible aortic valve prosthesis: notable results of hydrodynamic testing and experimental trials
Aims
A shortcoming common to all existing designs of mechanical cardiac valve prostheses is an increased trombogenicity caused, among other factors, by the lack of hydrodynamic compatibility between the luminal part of the prosthesis and the patterned blood flow. The aim of the study is to design and test our new mechanical aortic valve prosthesis to exclude life-long anticoagulation treatment.
Materials and methods
Standard hydrodynamic tests of the new prosthetic valve have been carried out for comparing with the other existing valve designs. A new method for the heart valve prosthesis testing in a tornado-like flow has been developed. The valve function has been verified in a swine excluding the anticoagulation treatment during the period of time exceeding six months.
Results
The significant advantage of the new prosthesis in the standard hydrodynamic tests has been demonstrated. The tests in the tornado-like flow have shown that only this prosthesis allows maintaining the pattern, the head and flow rate characteristics of the tornado-like jet. Upon implanting the new prosthesis in the aortic position in a swine, the good performance of the valve without anticoagulation therapy has been confirmed in the course of more than six months.
Conclusion
Obtained has been the evidence of the merits of the new mechanical aortic valve owing to the due consideration of the hydrodynamic peculiarities of the aortic blood flow and the creation of the design providing the proper hydrodynamic compatibility