Protective effect of hyperpolarized arrest with blood cardioplegic solution containing pinacidil on ischemic myocardium during cardiopulmonary bypass / 中华麻醉学杂志

ABSTRACT

Objective To compare the myocardial protective effect of hyperpolarized cardioplegic arrest with pinacidil against that of depolarized hyperkalemic arrest during cardiopulmonary bypass Methods Eighteen healthy mongrel dogs of both sexes weighing 10 15kg were divided into three groups of six each, according to the cardioplegic solution infused into aortic root after aortic cross clamp was applied; group A received 4℃ standard St Thomas solution (K +16mmol/L); group B 37℃ St Thomas solution (K +5mmol/L) containing pinacidil (50?mol/L) mixed with blood (the ratio was 11);group C 4℃St Thomas solution (K + 5mmol/L) containing pinacidil(50?mol/L) mixed with blood (1∶1) The global ischemic time was 60min followed by 30min reperfusion Myocardial tissue was taken before and 30min, 60min after aortic cross clamping and 30min after reperfusion for determination of myocardial content of adenine nucleotide and MDA and ultrastructure examination with electron microscope Hemodynamics (BP,CVP,PCWP,CO,CI and LVSW) was also measured before aortic cross clamping and 15,30min after declamping Results Significant ischemic and reperfusion damages were found in group A, while there were only mild damages in group B and C Hemodynamics recovery after aortic declamping was significantly better in group C than that in group A and B Conclusions Myocardial protective effect of hyperpolarized arrest produced by blood cardioplegic solution containing pinacidil is superior to that of traditional depolarized hyperkalemic arrest and hypothermic hyperpolarized cardioplegia is better than normothermic