Представлен анализ результатов хирургического лечения сочетанного атеросклеротического поражения сонных и коронар-ных артерий 143 пациентов при различных вариантах хирургической тактики. В 1-й группе пациентов основными критериями вы-бора этапности оперативного лечения являлись степень атеросклертического поражения коронарного и каротидного бассейнов, а также тяжесть клинических проявлений ИБС и ХНМК. Во 2-й группе пациентов хирургическая тактика определялась с учетом результатов исследований функционального резерва перфузии миокарда и головного мозга. В 3-й группе тактика одномоментного хирургического лечения была основана только на наличии у пациентов сочетанного, гемодинамически значимого атеросклеротиче-ского поражения сонных и коронарных артерий.На основании полученных результатов показано, что функциональная оценка резерва перфузии миокарда и головного мозга позволяет дифференцировать пациентов высокого риска с сочетанным атеросклеротическим поражением коронарного и каротид-ного бассейнов, что способствует выбору оптимальной тактики хирургического лечения. Одномоментные операции целесообразны у больных со сниженным резервом как коронарного, так и мозгового кровообращения. При этом риск мозговых и кардиальных по-слеоперационных осложнений у таких пациентов не выше, чем при этапном лечении.Ключевые слова: каротидная эндартерэктомия, аортокоронарное шунтирование, сочетанное поражение. the article provides surgical treatment outcomes of combined atherosclerotic lesions of carotid and coronary arteries in 143 patients who underwent different surgical treatment tactics. the major criteria for the choice of surgical treatment stages in patient Group 1 were degree of carotid and coronary circulation lesion and severity of clinical manifestations of CAd and chronic cerebrovascular insufficiency. Surgical treatment for patient Group 2 was identified taking into account the study data of functional reserve of myocardial and cerebral perfusion. In patient Group 3 the tactics of simultaneous surgical treatment was based only on the presence of combined, hemodynamically significant atherosclerotic lesion of carotid and coronary arteries. ANALYSIS OF THE SURGICAL OUTCOMES OF COMBINED ATHERSCLEROTIC LESIONS OF CAROTID AND CORONARY ARTERIESthe outcomes showed that functional evaluation of myocardial and cerebral perfusion reserve allows differentiation of high risk patients with combined atherosclerotic lesion of carotid and coronary circulation and thus contributes to the choice of the best possible surgical treatment tactics. Simultaneous surgeries are reasonable for the patients with lowered reserve of both coronary and cerebral circulation. Moreover, the risk of cerebral and cardiac postoperative complications in such patients is not higher than that after staged surgical treatment.
To determine the results of the transmission of electrical energy through the power line from the source to the consumer, it is necessary to have accurate information about the parameters of such line. Determining these parameters for operating lines with a minimum error is quite a laborious process. But if a researcher is interested only in voltages and currents at the end and at the beginning of a homogeneous section of a three-wire transmission line, then it is sufficient to use the theory of multipoles. In particular, the theory of eight-poles. The article presents the method of experimental determination of the longitudinal and transverse parameters of the studied transmission line. The study used the methods of natural experiment using an appropriate fleet of electrical devices, and methods of indirect measurement of the desired parameters. The experiment consists of six stages; on the basis of the obtained data, it becomes possible to determine the numerical values of the main parameters of the studied section of power transmission lines, with which it is possible to establish a quantitative relationship between the input and output characteristics of electrical energy. In addition, the described method, in principle, can be applied to the analysis of active eight-terminal networks of a similar design. This means that the proposed methodology can provide a comprehensive analysis of the studied object and will help to identify the parameters of an overhead power line at the construction stage or for its connection to the consumer. The article presents the experimental setup scheme, describes the experimental methods, and estimates the error of the calculation results.
Electrical energy from the place of its generation is transmitted to consumers of various capacities. The distance from the source of electrical energy to the consumer can vary from several meters to several thousand kilometers. In this regard, the accurate determination of the operating parameters of the power transmission line (PTL) is a mandatory and necessary condition for the PTL normal functioning. In the current-carrying parts of the double-circuit PTL there are six incident and six reflected waves of the electromagnetic field. They determine voltages and currents. A scheme is proposed for the distribution of these waves along linear wires of a homogeneous section of a double-circuit PTL. This scheme shows that the current-carrying parts of the adjacent wires have a significant impact on voltages and currents in one wire. This scheme illustrates the distribution of the amplitude values of electromagnetic field waves, defined as the integration constant. Using the integration constants, the propagation constants of electromagnetic waves along the linear wires of the PTL and the corresponding wave impedances, one can obtain the amplitude values of the incident and reflected waves at any point of the double- circuit PTL, and hence the currents and voltages in the double-circuit PTL. The article presents a method for determining the currents and voltages in a double-circuit PTL according to the load. The proposed method will allow determining the qualitative and quantitative indicators of electrical energy (induced voltage) appearing from each wire separately and provide the possibility of their elimination, which will improve the quality of electrical energy.
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