钾对再灌流早期室颤阈变化的影响

本实验在69只家兔上比较观察了高钾动脉血、血浆和正常动脉血对局部缺血心肌再灌流早期室颤阈(VFT)变化的影响。实验结果表明,缺血心肌用正常动脉血再灌流可使其VFT在灌流1分内迅速下降,然后逐渐回升。其中氧的恢复和钾的改变对VFT下降程度影响不同。缺血后用血浆再灌流,其VFT下降程度与缺血后用正常动脉血再灌流相比无显著性差异;而用高钾动脉血再灌流比用正常动脉血再灌流VFT下降程度轻(P<0.05)。本实验结果提示,在再灌流心律失常产生中缺血时所积累的钾的突然冲洗和再分布可能起更重要的作用。

Effect of hyperkalemia on changes in ventricular fibrillation threshold (VFT) during the early phase of reperfusion

Effects of hyperkalemia, plasma and normal arterial blood on changes in VFT during the early phase of reperfusion of regional ischemic myocardium were observed in 69 rabbit hearts. It Was shown that VFT was lowered rapidly within the first minute after reperfusion of regional ischemic myocardium with normal arterial blood and returned gradually later. The effects of the oxygen restoration and change in potassium on decrease in VFT were different. There was no significant difference in the diminution in VFT between the group of reperfusion with plasma and that with normal arterial blood but decrease in VFT in the group of reperfusion with hyperkalemia was smaller than that with normal arterial blood (P<0.05). These results suggest that abrupt washout and re distribution of potassium accumulated during myocardial ischemia may play more important roles in the genesis of reperfusion-induced arrhythmia.