[Effect of motor activity on the development of arrhythmia in experimental emotional stress].

Studies on monkeys and rabbits have shown that the experimental emotional stress can produce various disorders of cardiac rhythm: sinus tachycardia, atrial fibrillation, ventricular extrasystoles and paroxysmal ventricular tachysystoles. In these conditions the adrenaline content in the blood and myocardium is increased 3-4 times, the noradrenaline level is raised in the blood and decreased in the myocardium. Moderate motor activity leads to a relative decrease of adrenaline in the myocardium and arrest of cardiac arrhythmias. Marked motor activity on the contrary leads to an increase of the adrenaline and noradrenaline level in the myocardium and to the development of disorders of cardiac rhythm even up to ventricular fibrillation.