Basic research. Рубрика в журнале - Cardiometry
A new point on ECG: point l as identifier of rapid and slow ejection phases boundary
Статья научная
Aims Description of rapid and slow ejection phases in the cardiac cycle. Materials and methods The theory of cardiac cycle phase analysis and mathematical equations of hemodynamics were used in the paper. The equations were employed to verify the balance of the phase-related diastolic and systolic blood volumes reliant on phase durations, and the identification of boundaries of the cardiac cycle phases on the ECG. Further, synchronous ECG & RHEO recording was used. Aortic blood filling was studied in the stated phases. Results The location of boundaries of rapid and slow ejection phases is traced. The boundaries did not have a precise definition before. Thus, a new symbol, the L point, on the ECG has been introduced to identify the boundaries of phases S - L, L - j. Conclusion Previously the location of point j on the ECG was impossible to identify. It was considered as a hypothermic wave on the ECG that could not always be traced. Point j was defined as the j (Osborn) wave. Thereby the location of boundaries of rapid and slow ejection phases, where volumetric parameters were equal to the stroke volume, was not accurately identified. The research enabled detecting the ECG recording criteria of the rapid and slow ejection phases. The results of the present research are published for the first time.
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ECG periodic table: a new ECG classification based on heart cycle phase analysis
Статья научная
Aims The article considers the development of the periodic table of ECG phase changes which should reflect the variety of the ECG curves and can be used as reference system for diagnostics purposes. Materials and methods More than 5,000 ECG records were studied. They were recorded as original single-lead ECG of the ascending aorta. This fundamentally new ECG lead system reflects all processes in cardiovascular system. It was named by its developers the “ECG – HDA”. Basing on the theory of cardiac cycle phase analysis, the authors defined deviations from the normal ECG curve. Clinical tests were conducted and descriptions based on the laws of cardiometry were provided. Results A fundamentally new system of the ECG curve evaluation has been developed. Conclusion It is stated that all the variety of the actual ECG curves can be divided into 10 groups. Each group contains 4 levels of characteristic changes, starting from the norm up to and including critical deviations from the norm. The results are presented in the “ECG phase changes periodic table”. The table can be used for very precise diagnostics. The periodic table enables assessing the capabilities of the practical application of electrocardiography from a new point of view.
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Отчет
Research methodology and methods used in experiment Mars-500 held at the Institute of Biomedical Problems of the Russian Academy of Sciences in 2009-2011 are considered. 6 volunteers were isolated during 520 days in a sealed ground-based facility simulating space ship. Along with studies of the Martian crew, a number of satellite research were also carried out, which were devoted to the long-term program of medical and ecological investigations. This program was aimed at the study of the dynamics of adaptation abilities of the organism during its long stay in the natural social, living and industrial environments. For physiological investigations in experiment Mars-500, including the main experiment in a sealed ground-based facility and parallel long-term medical and ecological investigations in different regions of the world, the specialized hardwaresoftware complex "Ecosan-2007" was used. The methodology was based on the principles of prenosological diagnostics that have been further developed in the concept of adaptation risks and in the probabilistic approach to their evaluation. For evaluation of various components of the autonomous regulation state the method of heart rate variability (HRV) was used. It was concluded that the most important field in experiment Mars-500 was the investigation of the methodology of prenosological diagnostic in the preparation of a space mission to Mars.
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It is shown that initiated by action of molecular viscosity impulse flow, directed usually from the moving fluid to limiting it solid surface, can, under certain conditions, turn to zero and get negative values in the case of non-stationary flow caused by alternating in time longitudinal (along the pipe axis) pressure gradient. It is noted that this non-equilibrium mechanism of negative friction resistance in the similar case of pulsating blood flow in the blood vessels, in addition to the stable to turbulent disturbances swirled blood flow structure providing, can also constitute hydro-mechanical basis of the observed but not explained yet paradoxically high energy effectiveness of the normal functioning of the cardiovascular system (CVS). We consider respective mechanism of affecting on the stability of the normal work of CVS by environmental variable factors using shifting of hydro-dynamic mode with negative resistance realization range boundaries and variation of linear hydrodynamic instability leading to the structurally stable swirled blood flow organization.
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