KVT, 2016, Issue 184, pp.72-84
MODELING OF MECHANISMS AND HEMODYNAMIC EFFECTS OF HEART HYPERTROPHY
Institute of Software Systems of National Academy of Sciences of Ukraine, Kiev, Ukraine
Introduction. A term cardiac hypertrophy (HH) refers to the phenomenon of increasing of the size of the heart, or its separate part. HH’s initiators can be both mechanisms adapting the entire organism to different modes of blood supply and the development of genetic abnormalities. The lack of a clear distinction in understanding mechanisms of these processes creates problems of diagnosis and treatment of pathological HH. In our opinion, a computer modeling of main hemodynamic effects of different forms of HH is able to shed light on mechanisms of HH and help in clarifying of this distinction.
The purpose of this article is to describe a mathematical model (MM) able to simulate basic hemodynamic effects of the adaptive and pathological forms of HH.
Results. MM describes the pumping function of the heart and vascular hemodynamics in a large and small circulations. MM also takes into account the mechanism of baroreflector regulation of the heart and blood vessels. The heart model quantitatively connects the mean values of flow, pressure and blood volume in each ventricle with its end-diastolic elasticity (C) and input blood pressure. The computer simulation showed that changes of central hemodynamics under left ventricle’s pathological hypertrophy can be satisfactorily reproduced via proper decrease of left ventricular parameter C. The adaptive HH is modeled by combining two procedures: i) growth of C of both ventricles of the heart; ii) adequate lowering of the tone of the cardiac sympathetic nerve.
Conclusions. Despite the MM satisfactorily simulates main effects of HH, its several links are still unclear thus the future advanced MM should include humoral, central neural regulator contours, as well as mechanisms providing energy balance both in cardiac myocites and at organism-scale.
Keywords: mathematical model, human cardiovascular system, computer simulation, adaptive hypertrophy, pathology.
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