单纯消融犬心外膜脂肪垫的远期心电生理效应

The long-term electrophysiological effects of epicardial fat pad ablation in dogs

目的探讨系统消融犬心外膜脂肪垫（完全去迷走神经）的远期心电生理效应。方法成年雄性杂种犬16条，随机分为消融组和假手术组（各8条）。消融组犬经开胸途径消融心外膜所有可视脂肪垫，假手术组仅进行开胸手术。术后8周行心内电生理检查，测定右心房、左心房、左心室、右心室心尖部及右心室流出道等部位的不应期，并进行房性及室性快速心律失常的诱发。结果术后8周实验组基础心率（163．8±12．2）~／min显著高于假手术组对（122．7±13．0）次／min（P〈O．001）；消融组犬的右心房、左心房、左心室、右心室心尖部及右心室流出道不应期分别较假手术组显著缩短（除右心室心尖部P=0．012外，其他部位P〈O．001），同时该组的快速房性心律失常诱发率显著增加（P=0．04），两组间的室性快速心律失常诱发率差异无统计学意义。结论仅消融犬心外膜脂肪垫可能具有远期致心律失常作用，尤其在心房水平。

Objective To investigate the long-term electrophysiological effects of systemic atrial epi- cardial fat pad ablation （to achieve complete vagal denervation）. Methods Sixteen male mongrel adult dogs were randomly divided into the experimental group （n = 8 ） and the sham-operation group （n = 8 ）. In experi- mental group, the dogs underwent ablation for all visible atrial epicardial fat pad until complete vagal denerva- tion was achieved, while the dogs in the sham-operation group underwent thoracotomy only. After 8 weeks, the electrophysiological study was performed to measure the effective refractory period （ERP） of atrium and ven- trides,and induce atrial tachycardia and ventricular tachycardia. Results The baseline heart rate of experi- mental group was higher than that in the sham-operation group 8 weeks after the procedure [ （ 163.8-＋12. 2） bpm vs （ 122. 7-＋13.0） bpm,P〈0. 001J. The ERPs of the left and right atrium and ventricle in ablation group were significantly shorter as compared with that in the sham-operation group （P〈0.05 in all）. The inducibility of atrial tachycardia in ablation group was higher than that in the sham-operation group （P = 0. 041 ）, but the in- ducibility of ventricular tachycardia between the two groups was comparable. Conclusion Atrial epicardial fat pad ablation only approach may be proarrhythmia in the long-term,especially in the level of atrium.