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摇目的摇探讨经导管介入肾去交感神经对心力衰竭(简称心衰)犬心房基质和心房颤动(简称房颤)诱发的影响。方法摇22只犬随机分为假手术组(n=7),心衰组(n=8)和肾动脉消融组(n=7)。假手术组犬植入起搏器不起搏,喂养3周；心衰组植入起搏器后以240次/分的频率连续右室起搏3周,于起搏前、3周后分别取静脉血检测血管紧张素域( Ang域)和醛固酮水平；消融组先行双侧肾动脉消融,喂养8周,起搏器植入同心衰组。其中血清学指标测3次(消融前、消融8周后、起搏3周后)。所有犬在实验基线期和终点均进行心脏彩超、血压及电生理检测；处死动物后迅速取心房组织检测其基质变化。结果摇心衰组2只死亡,消融组1只未进入试验。淤与基线期相比,心衰组和消融组在起搏3周后股动脉血压均明显下降,且两者无明显差异；②与基线期相比,心衰组起搏3周后左室收缩末期压力(LVESP)降低[(167依21)mmHg vs (123依14) mmHg,P<0.01],左室舒张末期压力(LV鄄EDP)升高[(2.5依1.3) mmHg vs (25依3.7) mmHg,P<0.01]。消融组起搏3周后LVESP也降低,但LVEDP无明显变化；③与基线期相比,心衰组起搏3周后心房有效不应期明显降低,消融组无明显变化。消融组起搏3周后房颤平均诱发次数和时间明显少于心衰组；④与心衰组相比,消融组心房肌胶原容积分数、Ang域和转化生长因子鄄茁水平明显降低,血Ang域和醛固酮水平也明显降低。结论摇肾去交感神经可抑制长期快速心室起搏心房基质的改变和房颤的诱发。“,”Objective To investigate the role of renal denervation on atrial substrate and inducibility of atrial fibrillation ( AF) in dogs with pacing-induced heart failure( HF) . Methods Twenty-two dogs were randomized into sham-operated (n=7), HF (n=8) and renal artery ablation (RAA,n=7) groups. Sham-operated dogs were implanted with transvenous cardiac pacemakers without pacing. Dogs in the HF group were implanted with pacemakers and underwent right ventricular pacing for 3 weeks at 240 bpm to induce HF. Blood was collected before pacing and after pacing 3 weeks to measure the levels of angiotensinII(AngII)and aldosterone. The dogs in the RAA group received double renal artery ablation,subse-quently recovered for 8 weeks and underwent the same HF-inducing procedure. Blood was collected before RAA, after RAA 8 weeks and after pacing 3 weeks,which was the only difference. Echocardiography,blood pressure and electrophys-iological test were measured in all the dogs at the baseline and endpoint of the protocol. Then the hearts were quickly ex-cised and sections of atria were obtained from the three groups dogs to identify the changes of atrial substrate. ResultsThe majority of dogs completed the whole process except two deaths in the HF group and one exit in the RAA group. ①Compared with baseline, the systolic and dias-tolic femoral artery pressures in the HF group and the RAA group were reduced substantially after pacing for 3 weeks. No significant differences were observed in the femoralartery pressures after pacing for 3 weeks between the two groups. ②The dogs in the HF group exhibited reduced LVESP and higher LVEDP after 3 weeks pacing compared to baseline [(167 ±21)mmHg vs (123 ±14) mmHg;(2. 5±1. 3)mm-Hg vs (25±3. 7) mmHg, P<0. 01]. Dogs in the RAA group exhibited reduced LVESP compared to baseline,but constant LVDSP. ⅢCompared to the baseline, the right atrial effective refractory period decreased significantly after 3 weeks in the HF dogs but not in the RAA dogs. Dogs in the RAA group had shorter duration and less number of AF induced by 500bpm stimulation than the HF dogs.④Compared to HF group, the tissue levels of collagen volume fraction,AngIIand transfor-ming growth factor-β decreased significantly in the RAA group,the similarly trend was observed in plasma AngIIand aldo-sterone. Conclusions RAA suppress the atrial substrate remodeling and the AF vulnerability induced by long-term rapid ventricular pacing.