[The effective assessment of the severity of the course of a myocardial infarct by the sinus rhythm status].

Heart rhythm was studied in 35 patients with primary and in 33 patients with recurrent through-and-through myocardial infarction, in 46 patients with other forms of coronary heart disease and in 48 healthy subjects. Variation range and amplitude of mode were established to be the most significant characteristics of sinus rhythm which alongside with data on premorbid state and functional reserves of the heart can be used in the early hours after the onset for assessment of myocardial infarction severity. Sinus rhythm monitoring allows to suspect timely haemodynamic changes and detect precursors of myocardial fibrillation. Changes of sinus rhythm in response to administration of drugs make it possible to specify functional state of the heart and estimate quality of treatment.