摘要
目的通过不同干预方法,观察犬下腔静脉脂肪垫对窦房结及房室结功能的影响。方法选择16只犬开胸暴露下腔静脉脂肪垫,首先以固定的输出频率(20Hz)连续电刺激下腔静脉脂肪垫30 s,测量刺激前和刺激时窦房结恢复时间(SNRT)、校正SNRT(cSNRT)及AH、HV、RR间期变化;然后在直视下心外膜射频消融脂肪垫,再测定迷走神经刺激前后上述指标的变化。结果:14只完成试验。当电刺激下腔静脉脂肪垫时,AH间期与刺激前比较明显延长(122.2±12.4 m s vs 82.5±10.3 m s,P<0.05),其余指标未发生明显变化。电刺激通常在2 s内起效,AH间期随刺激电压增加而延长,在刺激停止3 s内恢复。射频消融下腔静脉脂肪垫后,刺激左右颈部迷走神经,SNRT、cSNRT及RR间期与刺激前比较有明显变化(分别为696.4±54.9 m s vs 467.5±45.4 m s;296.3±20.5 m svs 164.5±20.1 m s,400.3±39.1 m s vs 210.1±14.5 m s,P均<0.05),但AH间期及HV间期未发生明显变化。结论:刺激下腔静脉脂肪垫可使房室传导延迟,而不影响窦房结功能。消融下腔静脉脂肪垫可以消除迷走神经对房室结的支配。
Objective To better understand the physiological characteristics of inferior vena cava fat pad （IVCFP）. Methods 16 mongrel canines were investigated, The high-frequency electrical stimulation and radiofrequency ablation on IVCFP were used to measure the change of sinus node and AV node function, Results The experiment was completed in 14 canines, When IVCFP was stimulated, AH interval prolonged significantly （ 122.2 ± 12.4 ms vs 82.5 ± 10.3 ms,P 〈0.05 ）, And AH interval further prolonged with the increase of the voltage of electrical stimulation. But there was no significant difference of sinus node recovery time （SNRT） or correct SNRT found （ P 〉 0, 05 ）. After IVCFP was ablated, no para- sympathetic mediated negative dromotropic was found when cervical vagus nerve was stimulated. Conclusions High-frequency electrical stimulation on IVCFP can lead to atrioventricular conduction delay, Radiofrequency ablation of IVCFP can result in parasympathetic denervation on AV node totally.
出处
《中国心脏起搏与心电生理杂志》
2006年第1期63-65,共3页
Chinese Journal of Cardiac Pacing and Electrophysiology
关键词
电生理学
心脏脂肪垫
窦房结
房室传导
去迷走神经化
Electrophysiology
Epicardial fat pad
Sinus node
Atrioventricular conduction
Parasympathetic denervation
