心房电重构与房颤关系的基础研究

目的检查观测心房电生理改变与房颤（AF）发生和持续的关系，探讨心房电重构与房颤的内在联系。方法健康成年杂种犬14只（雌雄不拘，体重10．0～12．5kg），随机分为2组：对照组（A组）和起搏组（B组）。右侧开胸将电极置于右心房，以400次／min的频率快速起搏右心房（A组只手术不起搏），分别于实验开始及起搏6h后对每只犬进行电生理检查，测定心房有效不应期（AERP）。起搏开始及起搏后测定burst刺激诱发房颤的频率和持续时间。结果A组在整个时间内AERP无变化，B组心房快速起搏后，AERP明显缩短。A、B两组起搏前房颤的频率和持续时间差异无统计学意义。A组起搏前、后房颤的频率和持续时间无变化，B组心房快速起搏后房颤的频率增多，持续时间延长。结论快速心房起搏可以引起心房有效不应期缩短，即心房电重构。心房电重构造成的心房有效不应期等电生理变化促进了房颤的发生和维持，是心房电重构与房颤关系的基础。

The basic study on the connection between atrial electrical remodeling and atrial fibrillation

Objective To observe the relation between trial electrophysiologic change and the frequency and duration of atrial fibrillation （AF） through heart electrophysiologic examining, and to investigate the internal relation between atrial electrical remodeling and AF. Methods 14 healthy, adult and hybrid dogs （male or female, weight from 10.0 to 12.5 kg） were divided into control group （no pacing group, A group） and rapid atrial pacing group（B group） randomly：. The dogs＇right chest was opened, then electrode was inserted into right atrium, and then paced the right atrium rapidly by 400 times per minute. All dogs received electrophysiologic study at the beginning of experiment and 6 hours after atrial pacing, and atrial effective refractory period （AERP） was measured. The frequency and duration of atrial fibrillation induced by burst were measured respectively at the beginning of atrial pacing and 6 hours after atrial pacing. Results AERP and induced AF had no changes during the whole experiments in A group. In B group, AERP were significantly shorten, frequency and duration of induced AF increased after rapid atrial pacing. There was no significantly difference in AERP and frequency and duration of induced AF at baseline. Conclusion The atrial rapid pacing can lead to atrial electrical remodeling by shorting AERP. The electrophysiologic change of atrial electrical remodeling promote the occurrence and maintain of dogs＂ atrial fibrillation.