AbstractIn order to develop and implement the concept of prevention and treatment of fatal complications in the population of people with a high and very high cardiovascular risk, a risk calculation scale of emergence and progression of life-threatening arrhythmias and sudden death was created. It was based on the assessment of the state of heart rate variability and heart rate turbulence, the value of the coefficient - deceleration capacity (DC), and the length of the QTc interval on ECG.The creation of this scale was based on recommendations, protocols, and standards developed by the following: American Heart Association/American College of Cardiology Foundation/Heart Rhythm Society Scientific Statement on noninvasive risk stratification techniques for identifying patients at risk for sudden cardiac death (2013); Task Force of European Society of Cardiology and The North American Society of Pacing and Electrophysiology (2009). Sudden Death Forecast scale (SDFS) values are expressed in points from 1 to 10. From indicators of heart rate variability, we selected: (Total Power, Low Frequency, High Frequency, Low Frequency/High Frequency) and the duration of the QTc interval – and valued each indicator with 1 point. The change of heart rate turbulence indicators - parameters of acceleration (То) and deceleration (Тs) of sinus rhythm, and the coefficient of deceleration capacity (DC) are estimated at 2 points each. The distribution of points was made according to the prognostic value of each of the indicators. Points are awarded when the indicator goes beyond physiologically acceptable norms. The value of the points indicates the degree of adaptation of the cardiovascular system, necessary to maintain the active balance of the body with the environment, as well as the risk of life-threatening arrhythmias and sudden cardiac death. 1-2 points are very low risk, and 3-4 points are low risk. SDFS = 5-6 points: indicates a state of pronounced tension of regulatory systems and mobilization of protective mechanisms, the risk of life-threatening arrhythmias is moderate. SDFS=7-8 points: a state of insufficiency of protective and adaptive mechanisms and excessive activation of regulatory systems which is no longer supported by appropriate functional reserves – the risk is high. 7 points - the body's hemostasis is preserved and works in a state of compensation, 8 points - the appearance of non-specific premorbid conditions. SDFS = 9-10 points: state of exhaustion, specific changes clearly prevail over non-specific ones, the risk of life-threatening arrhythmias and sudden death is very high. This scale is available in a specially created program for PC. Sudden Death Forecast scale (SDFS)