Experimental Study of the Effects of Sodium Ion Concentrations on the Function of the Myocardium Exposed to Cardioplegic Ischemia

A new cardioplegic solution based on three natural dipeptides was developed and introduced at the Laboratory of Cardioplegia, A. N. Bakulev Research Center of Cardiovascular Surgery. The electrolyte composition of the solution corresponded to the category of intracellular cardioplegic solutions. The results of 60 experiments on isolated rat hearts were analyzed for choosing the optimal concentration of sodium ions (35, 60, or 80 mmol/liter). The composition of the studied cardioplegic solutions was selected by ion concentrations in the intra- and extracellular fluid. Earlier and most effective recovery of cardiac function with minimum rhythm and conductivity disorders was observed in the group treated with cardioplegic solution with sodium ion concentration of 60 mmol/liter.