缺血再灌注对家兔房室传导功能影响的实验研究

Effects of heart ischemia-reperfusion on atrioventricular node conduction in rabbits

目的 探讨缺血 再灌注对家兔心脏房室传导功能的影响 ,为临床防治提供实验依据。方法 以家兔为实验对象 ,开胸暴露心脏 ,通过结扎及再通右冠状动脉 ,建立房室结缺血 再灌注模型 ,监测血流动力学、希氏束电图及体表心电图 ,观察不同时间缺血及缺血 再灌注时的AH及HV间期的变化。结果 结扎右冠状动脉后 ,94 8%的动物出现AH间期明显延长 (P <0 0 1) ,再灌注后延长的AH间期明显缩短 (P <0 0 1) ;缺血 12 0min再灌注组 ,AH间期恢复结扎前水平后 ,随着再灌注的继续 ,AH间期则再次出现延长。结论 缺血可引起家兔在体心脏房室传导功能障碍 ,及时的再灌注可使房室传导功能完全恢复 。

Objective To study the effects of heart ischemia reperfusion on conductive function of atrioventricular node (AVN) in rabbits. Methods Animal models of ischemia reperfusion of AVN were established by ligating and reopening the right coronary artery of rabbits. A total of 60 adult rabbits were divided into control groups ( n =10), right coronary artery occlusion group ( n =10), and ischemia reperfusion groups with ligation of the right artery occlusion for 10, 30, 60 and 120 min respectively ( n =10 for every subgroup). The hemodynamics, His bundle electrography and epicardial electography were carried out and recorded. Results After occlusion of right coronary artery, 94.8% animals in experimental groups were found to have prolonged atrial His interval (AH) ( P <0.01) when compared with control group, but His ventricular interval (HV) and blood pressure (BP) had not obviously changed. After reperfusion, prolonged AH intervals were shortened dramatically ( P <0.01). In ischemia/reperfusion group for 120 min, AH intervals were found to recover firstly, and then prolonged again in the process of reperfusion. Conclusion Ischemia can induce the dysfunction of the AVN conduction of rabbits. Early reperfusion is essential for the full recovery of the atrioventricular conduction function, and delayed reperfusion results in part recovery.