经心外膜射频消融治疗心房颤动的实验研究

为探讨射频消融治疗心房颤动（简称房颤）的可行性，对１０条犬进行单心房Ｂｕｒｓｔ刺激和药物＋心房电刺激建立房颤模型并进行心房外膜多条径线的消融。结果显示：消融径线为连续和透壁性损伤；消融后药物＋心房电刺激的房颤诱发率和平均持续时间与消融前比较差异有高度显著性（５８％ｖｓ１００％，４．５ｓｖｓ２０３．５ｓ，Ｐ均＜０．０１）；校正窦房结恢复时间和窦性心率分别较消融前明显延长６５％（１２９±５１ｍｓｖｓ７８±３４ｍｓ）和下降１２％（１５０±６３ｂｐｍｖｓ１７０±３５ｂｐｍ），而房室传导功能和心脏功能无显著性变化。提示射频消融治疗房颤是可行的，其主要机制为消融径线有效地分离阻隔了参与房颤折返环的心房肌群。１条犬消融后发生持续性窦性停搏，可能是损伤窦房结动脉所致

Epicardial Application of Atrial Radiofrequency Ablation to Treat Atrial Fibrillation in Canine Model

To assess the feasibility of atrial fibrillation treatment with radiofrequency ablation of the atrium,multiple lines of radiofrequency ablation were produced around the atrial epicardium of 10 canine models.The results showed both of the inducible rate (58% vs 100%, P <0.01) and duration(4 5 s vs 203 5 s, P <0.01) of atrial fibrillation were significantly reduced after the contiguous transmural lesions were created by radiofrequency ablation.Corrected sinoatrial node recovery time was makedly porlonged by 65% (127±51 ms vs 78±34 ms) and sinus rate was droped down by 12% (150±63 bpm vs 170±35 bpm),without any significant change in the atrioventricular conduction and cardiac function after ablation.These results suggest that it may become possible for radiofrequency ablation to treat atrial fibrillation,when the atria are divided into several isolated parts and reentry circuits of atrial fibrillation are blocked by transmural ablation lines.Meanwhile,this ablation procedure can also damange the sinoatrial node artery.