[01] Mbaya Ilunga Edouard, Mechanical Section, Higher Institute of Applied Techniques, Kinshasa, Democratic Republic of the Congo. [02] Beya Dibue Jean-Pierre, Laboratory Section, Higher Institute of Medical Techniques, Kinshasa, Democratic Republic of the Congo. [03] Mansiantima Lutete Doris, Department of Physics and Applied Sciences, Faculty of Science, National Pedagogical University, Kinshasa, Democratic Republic of the Congo. [04] Dzama Likwanda Yohanan, Department of Physics and Applied Sciences, Faculty of Science, National Pedagogical University, Kinshasa, Democratic Republic of the Congo. [05] Mutombo Muana Donat, Mechanical Section, Higher Institute of Applied Techniques, Kinshasa, Democratic Republic of the Congo. [06] Beta Mwakatita Mura, Mechanical Section, Higher Institute of Applied Techniques, Kinshasa, Democratic Republic of the Congo. [07] Gbabete Kpalakoni Jean-Richard, Mechanical Section, Higher Institute of Applied Techniques, Kinshasa, Democratic Republic of the Congo. [08] Benjamin Zoawe Gbolo, Department of Biology, Faculty of Science, University of Kinshasa, Kinshasa, Democratic Republic of the Congo. [09] Pius Tshimankinda Mpiana, Department of Chemistry, Faculty of Science, University of Kinshasa, Kinshasa, Democratic Republic of the Congo. [10] Koto-Te-Nyiwa Ngbolua, Department of Biology, Faculty of Science, University of Kinshasa, Kinshasa, Democratic Republic of the Congo.

Blood flow dynamics in arteries is an underlying factor for much vascular pathology. A better understanding of these dynamics could improve the prediction and diagnosis in both healthy and pathological situations. The study of the mechanical properties of aorta will help to understand the normal and pathological situation and to predict their adaptation to changing circumstances. The aorta is continuously exposed to blood pressure caused by the pulsatile effect of the heart. These stresses are noticed by elastic deformation of the organ. In the present study, we have developed a mathematical model that allowed us to evaluate the blood-aorta interaction by resolving differential equations that describe biomechanical characteristics of aorta. The present study revealed that the stress exerted by the blood flow in aorta causes its elastic deformation. However, we reported for the first time that the resulting aortic deformation threshold is higher than the standard commonly values (7-10% vs 12%). The experimental data acquired with the help of Doppler echo device and the computer simulation with MATLAB® software package permitted to confirm the perfect agreement between the experiments and the theoretical predictions.

Blood Dynamics, Blood Pressure, Aorta, Deformation, Simulation, Biomechanics

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