S1S2和S1S2S3两种程控刺激模式诱发猪心室颤动模型的效果

To compare the effects of S1S2 and S1S2S3 programmed stimulation modes on inducing ventricular fibrillation in pigs

目的评价S1S2S3(300/200/190 ms)程控刺激模式诱发心室颤动(VF)的效果。方法本实验研究选取16头雄性家猪随机分为两组:S1S2组(n=8)和S1S2S3组(n=8)。分别经右心室内膜给予40 V、8∶1、步长-10 ms的S1S2(300/200 ms)或S1S2S3(300/200/190 ms)程控刺激。比较两种程控刺激模式诱发VF的效果和除颤成功率。结果两组家猪均诱发VF成功。S1S2组诱发VF的S2配对间期主要集中在160~190 ms(6/8),S1S2S3组诱发VF的S3配对间期也集中在160~190 ms(7/8)。S1S2组诱发VF程控刺激的次数明显多于S1S2S3组[9.5(4.0,17.5)vs.3.0(1.3,6.3),P=0.040]。S1S2组诱发VF所消耗时间(s)也明显长于S1S2S3组[71.0(27.0,132.8)vs.19.5(5.0,45.5),P=0.046]。经过VF 4 min后两组猪均复苏成功。S1S2组和S1S2S3组的除颤次数差异无统计学意义(1.5±0.5 vs.1.8±0.9,P=0.506)。结论应用程控刺激方法诱发VF猪模型是稳定、可靠的。S1S2S3模式比S1S2模式诱发VF需要程控刺激的次数更少,耗时更短。

Objective To evaluate the effect of S1S2S3(300/200/190 ms)programmed stimulation mode on ventricular fibrillation(VF)induction.Methods 16 male domestic pigs were randomly divided into two groups:S1S2 group(n=8)and S1S2S3 group(n=8).The two groups were given 40 V,8∶1,step size-10 ms,S1S2(300/200 ms)or S1S2S3(300/200/190 ms)programmed stimulation via the right ventricular intima.The effects of VF induced by two programmed stimulation modes and the success rate of defibrillation were compared.Results VF was successfully induced in all the animals of both groups.The S2 pairing interval of inducing VF in S1S2 group was mainly concentrated on 160-190 ms(6/8),and the S3 pairing interval of inducing VF in S1S2S3 group was also concentrated on 160-190 ms(7/8).The numbers of programmed stimulation inducing VF in S1S2 group were significantly higher than those in S1S2S3 group[9.5(4.0,17.5)vs.3.0(1.3,6.3),P=0.040].The time(s)spent in inducing VF in S1S2 group was also significantly longer than that in S1S2S3 group[71.0(27.0,132.8)vs.19.5(5.0,45.5),P=0.046].All the animals in the two groups were resuscitated successfully after 4 min of VF.There was no significant difference in the number of defibrillation between S1S2 group and S1S2S3 group(1.5±0.5 vs.1.8±0.9,P=0.506).Conclusions VF induced by programmed stimulation is stable and reliable in cardiac arrest(CA)animal models.S1S2S3 mode induces VF faster and takes less time than S1S2 mode.