射频消融心外膜脂肪垫治疗犬肺静脉左房交界处起源的心房颤动

Radiofrequency ablation of the epicardial fat pad for the treatment of atrial fibrillation arising from the pulmonary vein-atrium junctions in dogs

目的探讨射频消融心外膜脂肪垫对左房-肺静脉交界触发的局灶性心房颤动(简称房颤)治疗的有效性。方法成年杂种犬10只,心外膜脂肪垫注射氯化乙酰胆碱(Ach)+左房短阵快速电刺激诱发犬左房-肺静脉交界触发的局灶性房颤模型。4极电极分别缝置于左房、右房、左肺静脉与左房交界处,记录最快激动部位。直视下射频消融心外膜脂肪垫。于房颤模型建立前后,及消融脂肪垫后测量左、右房有效不应期(ERP),肺静脉-左房交界处ERP、计算房颤诱发率。术毕处死实验犬行组织学检查。结果所有犬均能通过脂肪垫注射氯化Ach+左房短阵快速电刺激诱发出左房-肺静脉交界触发的局灶性房颤,建模后左房、右房、肺静脉-左房交界处的ERP均较建模前显著缩短(分别为94±33 ms vs 139±9 ms,104±17 ms vs 137±9 ms,104±17 ms vs 137±9 ms;P均<0.01)。脂肪垫消融后房颤诱发率与消融前比较显著降低(45%±16%vs 86%±4%,P均<0.01);左房、右房ERP无变化,肺静脉-左房交界处不应期显著延长(137±8 ms vs 104±17 ms,P<0.01)。组织学未发现除脂肪垫外的其它消融损伤灶。结论射频消融心外膜脂肪垫对肺静脉-左房交界触发的局灶性房颤治疗有效。

Objective To evaluate the feasibility of the fat pad radiofrequency （RE） ablation in atrial fibrillation （AF） arising from the pulmonary vein-atrium junctions. Methods Ten dogs were included in this study. A thoracotomy was performed and a needle with a polyethylene tube attached was inserted into fat pad containing autonomic ganglia at the base of the PV. Burst stimulation was performed to induce AF. During AF, after the fastest activity was recorded, the fat pad RF ablation was performed. Effective refractory periods （ERPs） in left atrium, right atrium, and the pulmonary vein-atrium junction were measured before and after RF ablation. The inducibility and the last time of AF were also mearsured before and after ablation. Results AF arising from the PVs was induced in all dogs after Ach injection and burst stimulation, and the ERPs were shortened at left atrium, right atrium and the pulmonary vein-atrium junction （94 ± 33ms vs 139 ± 9ms, 104 ± 17ms vs 137 ± 9ms, 104 ± 17ms vs 137 ± 9ms ;P 〈 0.01 ）. After fat pad RF ablation, the ERP in pulmonary vein-a- trium junctions was prolonged （ 104 ± 17ms vs 137 ± 8 ms, P 〈 0.01 ）, and the AF inducibility was decreased（45% ± 16% vs 86% ± 4%, P 〈 0.01 ） . There was no other lesions except for the fat pad after RF. Conclusion The AF can be eliminated by RF fat pad ablation.