[Change in catecholamine and acetylcholine concentration in myocardial tissue in assisted circulation]

The authors stress the importance of reactions associated with the concentration of biologically active substances in the body tissues, in particular their influence on the contractility and escitability of the heart muscle. They cite the results consequent upon a study on the catecholamines and acetylcholine content in the myocardial tissue of the left ventricle and left auricle of the heart before and after institution of an auxilliary circulation effected with the aid of a valveless pump connected to the subclavicular artery in 22 dogs. An analysis of the results demonstrated that by producing counter-pulsation with the pump the concentration of catecholamines and acetylcholine in the tissues of the left head diminishes, but the fall of the catecholamines concentration does not reach the level typical of cardiac insufficiency. The authors believe that investigations of this kind may help elaborate optimal conditions and a permissible duration of the auxilliary circulation.