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Doppler measurement of vessel parameters
NÁTHEROVÁ, Markéta
Ultrasound investigation is the most common and most readily available current advanced diagnostic method. Ultrasound can be used to track and image moving structures such as cardiac valves or flowing blood {--} these methods are based on the so-called Doppler phenomenon. Using the Doppler phenomenon, it is possible to determine the velocity and direction of movement of the measured object. The objective of this work was to track the changes of vascular flow and pulse rate depending on the degree of tolerance of exercise attained by the test persons, the stress (load) and ambient temperature changes. For this purpose, 2 groups were defined where the first group consisted of individuals adapted to the stress, while the members of the second group were untrained. To measure the vascular parameters we used a Doppler meter, HiDop 300. The LCD display of the instrument, or alternatively the monitor of a connected computer, provide images of the measured spectral Doppler curve as well as its parameters (heart rate HR, resistance index RI, pulsatility index PI, systolic/diastolic ratio, mean frequency). The work is concerned with the impact of physical load and cold-related stress on the circulatory system in the vessels. The haemodynamics of the vascular system depends on the type and intensity of the load. The formulation of results of the work, however, must account for a number of internal factors (age, sex, health {\dots}) and external factors (ambient temperature, air flow {\dots}) that are themselves associated with various changes in the circulatory system. For example, reduction of peripheral vascular contractility in the elderly, disruption of vascular wall elasticity by depositing fatty substances or increased heart rate due to the stress stimulus. The main advantage of a Doppler instrument and all ultrasound methods is to be seen in the fact that it is a non-invasive method, and has no adverse effects on the investigated person, such as the effects associated with roentgen radiation, provided, however, that appropriate intensity of ultrasound radiation has been chosen.
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Fyzikální modelování srdečně cévní soustavy na ÚT AVČR
Pražák, Josef
The physical modeling remains an important tool for theoretical and practical studies of CVS. Nowadays, the most important applications of physical modeling of CVS are the testing and developing of artificial substitutions of CVS elements and the application of it as a counterpart for mathematical models. On the IT, the physical modeling of the CVS flow phenomena is developed since the last century (more then six years) in the Laboratory of biomechanics. In its contemporary state, the IT physical model of CVS represents a universal system (construction kit) suitable for a large class of applications.
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