Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ab...Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular(AV)nodes for treating patients with bradyarrhythmia.Methods:A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015.Under the guidance of fluoroscopy and/or three-dimensional geometry by 64-slice spiral computed tomography,atrial activation sequence in sinus rhythm was mapped.Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology(RMT)system.Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm.Areas surrounding the sinus node,AV node,and the phrenic nerve were avoided.Results:Thirteen patients completed the studies.Ablation was successfully performed in 12 patients and failed in one.The highfrequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications.The vagal reaction was observed before the improvement of the sinus and AV node function.No complications occurred during the procedures.Patients were followed up for a mean of 13.0±5.9 months.During the follow up ten patients remained free of symptoms,and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope.The heart rate of post-ablation was higher than pre-ablation(69.0±11.0 vs.49.0±10.0 beats/min,t=4.56,P=0.008).The sinus node recovery time,Wenckebach block point,and atrium-His bundle interval were significantly shorter after ablation(1386.0±165.0 vs.921.0±64.0 ms,t=7.45,P=0.002;590.0±96.0 vs.464.0±39.0 ms,t=2.38,P=0.023;106.0±5.0 vs.90.0±12.0 ms,t=9.80,P=0.013 before and after ablation procedure,respectively).Conclusions:Ablation of sinoatrial and AV nodal peripheral fibrillar myocardium electrical activity might provide a new treatment to ameliorate paroxysmal sinus node dysfunction,high degree AV block,and vagal-mediated syncope.展开更多
文摘Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular(AV)nodes for treating patients with bradyarrhythmia.Methods:A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015.Under the guidance of fluoroscopy and/or three-dimensional geometry by 64-slice spiral computed tomography,atrial activation sequence in sinus rhythm was mapped.Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology(RMT)system.Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm.Areas surrounding the sinus node,AV node,and the phrenic nerve were avoided.Results:Thirteen patients completed the studies.Ablation was successfully performed in 12 patients and failed in one.The highfrequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications.The vagal reaction was observed before the improvement of the sinus and AV node function.No complications occurred during the procedures.Patients were followed up for a mean of 13.0±5.9 months.During the follow up ten patients remained free of symptoms,and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope.The heart rate of post-ablation was higher than pre-ablation(69.0±11.0 vs.49.0±10.0 beats/min,t=4.56,P=0.008).The sinus node recovery time,Wenckebach block point,and atrium-His bundle interval were significantly shorter after ablation(1386.0±165.0 vs.921.0±64.0 ms,t=7.45,P=0.002;590.0±96.0 vs.464.0±39.0 ms,t=2.38,P=0.023;106.0±5.0 vs.90.0±12.0 ms,t=9.80,P=0.013 before and after ablation procedure,respectively).Conclusions:Ablation of sinoatrial and AV nodal peripheral fibrillar myocardium electrical activity might provide a new treatment to ameliorate paroxysmal sinus node dysfunction,high degree AV block,and vagal-mediated syncope.
文摘目的探讨房性心动过速与窦房结功能障碍的关系,研究其可能的发病机制。方法 30只成年新西兰兔随机分成实验组和对照组,每组15只,开胸将临时起搏电极缝于右房,实验组以350次/分的频率进行快速心房起搏,每天8 h,连续7 d;于起搏第1,3,7 d测试静息心率、固有心率及校正的窦房结恢复时间(CSNRT),并于实验第7天处死动物,取出窦房结组织,应用逆转录-聚合酶链式反应技术测定HCN4及RyR2 mRNA表达情况。结果经快速心房起搏后7 d,实验组静息心率、固有心率较对照组明显减慢(219.71±3.59次/分vs 272.14±9.44次/分,202.00±4.76次/分vs 224.57±4.50次/分,P均<0.05);CSNRT较对照组明显延长(96.00±3.56 ms vs 73.43±4.62 ms,P<0.05);HCN4及RyR2 mRNA表达明显减弱(0.37±0.04 vs 0.65±0.05,0.49±0.09 vs 0.84±0.06,P均<0.05)。结论快速房性心律失常可导致窦房结功能障碍,其可能的发病机制是HCN4及RyR2表达的减弱。