交感神经对犬快速右心房起搏诱发阵发性心房颤动的影响

目的研究交感神经对犬快速右心房起搏所诱发的心房颤动(房颤)中的作用。方法选择杂种犬28只,随机分为4组:交感刺激组、交感离断组、异丙肾上腺素组(Iso组)、美托洛尔组(Met组),每组7只。各组分别于交感神经干预前后检测心房有效不应期(AERP)及快速右心房起搏的房颤诱发情况,观察各组交感神经干预对其的影响。结果与基础状态比较,交感刺激组和Iso组干预后AERP明显缩短(P<0.05),交感离断组和Met组AERP明显延长(P<0.01);Iso组房颤诱发率明显升高(P<0.01)。与交感刺激组和Met组比较,Iso组房颤诱发率明显升高(P<0.01)。随着AERP时程延长,房颤的诱发率逐渐下降,呈负相关线性趋势(r=-0.728,P=0.003)。结论交感神经活性与心房电重构有一定的联系,单纯刺激交感神经不能改变房颤的诱发频率,但交感神经递质可使房颤更易于诱发。

Effect of sympathetic nerve on rapid right atrial pacing-induced paroxysmal AF in dogs

Objective To study the effect of sympathetic nerve on rapid right atrial pacing-induced paroxysmal AF in dogs.Methods Twenty-eight hybrid dogs were divided into sympathetic nerve stimulating(SNS)group,sympathetic nerve dividing(SND)group,isoproterenol(Iso)group,and metoprolol(Met)group(7in each group).Their atrial effective refractory period(AERP)and AF inducibility were tested before and after intervention of sympathetic nerve.The effect of sympathetic intervention on rapid right atrial pacing-induced paroxysmal AF was observed.Results The AERP was significantly shorter in SNS group and Iso group,and significantly longer in SND group and Met group after intervention than before intervention(P<0.05,P<0.01).The AF inducibility was significantly higher in Iso group than in SND group and Met group(P<0.01),decreased gradually in a negative correlation linear manner with the prolonged AERP(r=-0.728, P=0.003).Conclusion Sympathetic nerve activity is related with atrial electrical remodeling. Electrical stimulation of sympathetic nerve cannot alter the AF inducibility and AF can be easily induced by sympathetic nerve transmitter.