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Information × Registration Number 0219U001588, 0116U004023 , R & D reports Title Improvement of intraoperative cardiac protection based on the analysis of temperature fields popup.stage_title Head Maksymenko Vitaliy Borisovich, Registration Date 08-02-2019 Organization M.M.Amosov National Institute of Cardio-Vascular Surgery of the Academy of Medical Sciences of Ukraine popup.description2 The novelty of the work lies in the determination of safe and effective methods of intraoperative protection of the heart based on the analysis of temperature fields under conditions of artificial blood circulation (IC), as well as obtaining a quantitative estimate of the temperature distribution in human myocardial tissues with controlled cooling and warming under conditions of artificial circulation. Controlling the temperature of the heart and body allows you to determine the safe time for stopping the blood supply, the uniformity of controlled suppression of metabolism in the controlled area, the functional state of the regional blood supply, its disruption and restoration during the operation stages. The complexity of the research and methods proposed in this work consists in combining methods and means of non-invasive temperature measurement under artificial blood circulation, which are aimed at increasing the effectiveness of intraoperative protection of the brain and heart, reducing the number of postoperative complications, early and more complete restoration of impaired myocardial functions brain after a period of their exclusion from the circulation and subsequent restoration of blood supply. For the first time, patterns of changes in the temperature field on the surface of the human heart under conditions of extracorporeal circulation, which correlate with the processes of heat exchange and heat transfer in the myocardium, reveal circulatory disturbances in the coronary vessels, which allow detection of ischemia zones in clinical studies. The principles of applying the method of infrared thermography in cardiac surgery practice under conditions of artificial blood circulation in the temperature range from + 4 С to + 38 С are scientifically substantiated and developed. The scientific novelty of the application of thermographic methods is to take into account data on the temperature distribution on the surface of the myocardium, which allows you to enter a personalized assessment of the intraoperative protection of the heart and brain. A method of non-invasive heart temperature control is proposed for visualizing the temperature field distribution on the myocardial surface, which allows to improve the segmentation of the cooled and heated areas on the thermal video of the heart and diagnose ischemic foci, as well as assess myocardial metabolism at different stages of perfusion, hypothermia and hyperthermia. To determine the temperature characteristics of the myocardium, a solution of the heat equation was obtained taking into account the function of myocardial temperature change over time in the process of hypothermia and cardiac hyperthermia. Models of heat exchange between the coronary vessels and the myocardium have been developed, which allow us to estimate the temperature gradient on the surface of the heart, calculate the temperature coefficients of cooling and myocardial warming, and the thermal diffusivity of the tissues, which allows to determine the presence of ischemic patches on the surface of the myocardium. Conducted clinical studies and analysis of the distribution of the temperature field on the surface of the heart and in the depth of the myocardial layer allow us to establish the relationship between the duration of warming and the depth of cooling of the heart and brain under conditions of artificial blood circulation. Product Description popup.authors Дуплякіна Віра Єгорівна Зінченко Геннадій Анатолійович Тарасова Лариса Дмитрівна Хітаб Омар Шликов Владислав Валентинович Яковенко Інна Григорівна Якубюк Сергій Олексійович popup.nrat_date 2020-04-02 Close