目的 比较比格犬和杂种犬制作的右心室快速起搏至房颤模型,选择出表达更加稳定的房颤动物模型.方法 雌性杂种犬与比格犬各8只采用完全随机设计,将8只杂种犬分为2组,每组4只,记为杂种犬对照组与杂种犬实验组;将8只比格犬分为2组,每组4只,记为比格犬对照组与比格犬实验组.各实验组在X线透视下,经颈外静脉将1条心室起搏电极植入右心室心尖.连接心室起搏电极与起搏器,起搏器埋于右侧颈部皮下.以240次/min快速起搏心室,送回动物房饲养.2周后测定血流动力学指标和电生理指标,处死,快速取出心脏,测定心脏重量等相关指标.结果 比格犬在心率,心脏系数,左心室内压这几个指标中与杂种犬比较差异均无统计学意义;比格犬对照组与杂种犬对照组心房不应期无明显差别;杂种犬实验组右心室快速起搏后心房不应期有下降趋势,但差异无统计学意义;比格犬实验组右心室快速起搏后心房不应期下降,差异有统计学意义(P<0.01);比格犬对照组与杂种犬对照组比较,房颤诱发率差异有统计学意义(P<0.05).结论 比格犬较杂种犬在右心室快速起搏至房颤模型中表达稳定,效果明显,有一定优势.
Objective To select a more stable animal atrial fibrillation (AF) model by comparing the beagle dog and mongrel dog model of rapid right ventricle pacing-induced AF.Methods Eight mongrel dogs were divided into experimental group and control group (4 in each group),and 8 beagle dogs were divided into experimental group and control group (4 in each group).A pacing electrode was placed in the right cardiac apex of the animals in 2 experimental groups under X-ray guidance and connected to the pacer subcutaneously placed in the right neck.The animals were rapidly paced (240 times/min) and then sent back to their house,after two weeks their hemodynamic and electrophysiological indications were detected.The animals were then sacrificed with their heart removed and weighed.Results No significant difference was found in the heart rate,coefficient of heart and left ventricular end-diastolic pressure between beagle and mongrel dogs.No obvious variation was observed in the atrial refractory period between the 2 control groups.The atrial refractory period was shorter in beagle dogs than in mongrel dogs after pacing (P 〈 0.01) with no obvious reduction in experimental group of mongrel dogs.The incidence of AF in control group of beagle dogs was significantly different from that in control group of mongrel dogs.Conclusion The beagle dog model of rapid right ventricle pacing-induced AF is better than the mongrel dog model of rapid right ventricle pacing-induced AF.