FUNCTIONAL RESPONSE OF THE CARDIOVASCULAR SYSTEM OF NORTHERNERS TO COLD TEST IN TEMPERATURE CONTRAST YEAR SEASONS

Cardio-hemodynamics and systemic hemocirculation of a person before and after cold test influence in contrast year seasons was investigated to study the influence of environmental temperature on various parts of the cardiovascular system. Heart rate, speed and time of transaortic blood flow in the aortic root were measured by echocardiography. Systolic and diastolic blood pressure was measured by tonometer on the stages of cardio-hemodynamics study. It was established that the person in clinostatic body position and in a state of relative rest had lower diastolic blood pressure, speed transaortic blood flow and performance of the heart in December than in June. The study showed that the body's response to cold test influence in the summer was characterized by decreased systolic blood pressure, increased heart rate and short-term reduction of cardio-hemodynamics. In winter, the period of low air temperature local freezing caused at first increase of systolic blood pressure, and in succeeding period decrease of systolic blood pressure relative to baseline values. Wherein, change in cardio-hemodynamics and chronotropic function of the heart was not found. The results showed reduced peripheral vascular tone, less venous return to the heart with a decrease of cardio-hemodynamics and myocardial performance of a person in the cold season. The reaction of the cardiovascular system to the local freeznig was more obvious in the summer and was accompanied by a positive chronotropic effect, decreased intracardiac and systemic hemodynamics during the period of circulatory homeostasis of the body after the test.