[The metabolic characteristics of nonesterified fatty acids in the myocardium of patients with paroxysmal tachycardias and their pathogenetic role in the origin of the heart rhythm disorders].

Twenty-one patients suffering from paroxysmal tachycardia (PT) were examined for metabolism of nonesterified fatty acids (NEFA) in the myocardium as well as for interrelations with the parameters of clinical electrophysiology. It has been shown that the main features of NEFA metabolism in the myocardium of RT patients lie in their high concentration in arterial blood and in the blood of the coronary heart sinus and in their high ratio of extraction by the myocardium both in the presence of sinus rhythm and during RT, which is of the pathogenetic importance in the origin of heart rhythm disturbances. NEFA exert different effects on the antegrade and retrograde (functional and effective) refractory periods of different parts of the conduction system of the heart, favouring the onset of their electrophysiological heterogeneity.