连续房室结功能曲线的慢快型房室结折返性心动过速的电生理特点及射频消融

目的探讨连续房室结功能曲线的慢快型房室结折返性心动过速（AVNRT）电生理特点及射频消融。方法共分A、B、C三组，A组35例，典型AVNRT；B组21例，非典型AVNRT；C组16例，伴连续房室结功能曲线的慢快型AVNRT。比较三组消融前后心房递增起搏或心房程序刺激时最大的AH间期（AHmax）、房室结前向有效不应期（ERP）、保持房室1：1传导的最快心房刺激时的刺激信号至QRS波起始（SR）与RR间期比值（SR／RR）。结果消融前后A、B、C三组AHmax和SR／RR均明显减少，A组ERP明显增长；而组间比较，A组AHmax减少幅度比B、C组明显大，P〈0.01。C组患者经冠状静脉窦口处递增起搏或程序刺激均可诱发出AVNRT。B组和C组还要增加从三尖瓣环至冠状静脉窦口的划线消融，可以提高消融成功率。结论伴房室结功能曲线的慢快型AVNRT患者经冠状静脉窦口处递增或程序刺激可提高AVNRT诱发率，除慢径路消融外，增加从三尖瓣环至冠状静脉窦口划线消融可提高消融成功率，AHmax和SR／RR也可作为房室结消融成功的指标之一。     

房室结功能曲线连续性房室结折返性心动过速患者的射频消融终点初探

目的　探讨房室结功能曲线连续性房室结折返性心动过速 (AVNRT)患者的射频消融终点。方法　在AVNRT患者中 ,对心房 A1 A2 和 A1 A2 A3程序刺激房室结功能曲线均呈连续性者为 组 ,A1 A2 刺激房室结功能曲线呈连续性而 A1 A2 A3刺激呈不连续性者为 a组 ,房室结功能曲线均呈不连续性者为 b组。行慢径区域消融后 ,对组间的电生理参数进行比较。结果　 组非典型 AVNRT的诱发率高于 组 (2 7.3 % vs5 .6% ,P<0 .0 5 )。在 I组和 a组 ,消融后最长 A2 H2 间期 (A2 H2 m ax)均比消融前有所缩短 ,但无显著性差异 (P>0 .0 5 ) ,而 b组则显著缩短 (3 76± 73 ms vs2 0 6± 5 6ms,P<0 .0 1)。消融后 组、 a组和 b组的最长 A3H3间期 (A3H3m ax)均比消融前显著缩短 (2 74± 71ms vs 196± 45 ms,P<0 .0 5 ;3 62± 91m s vs 2 2 6± 72 m s,P<0 .0 1;3 85± 88ms vs 2 19± 61ms,P<0 .0 1)。结论　非典型 AVNRT与房室结功能曲线的连续性有关。对于房室结功能曲线连续性的 AVNRT患者 ,消融后 A3H3max的缩短可作为消融终点的指标之一     

伴连续房室结功能曲线的房室结折返性心动过速的电生理特点

目的：探讨不存在房室结双径路特性的房室结折返性心动过速（AVNRT）的电生理特点。方法：102例AVNRT患分为3组：A组15例,存在连续房室结功能曲线,心房递增起搏时无AH间期跳跃（≥5ms)延长;B组21例,存在连续房室结功能曲线,心房递增起搏时有AH间期跳跃（≥50ms）延长;C组64例,存在不连续房室结功能曲线。比较3组患射频消融前后心房递增起搏时最大AH间期[AHmax(WCL)]、心房期前刺激时最大AH间期[AHmax(ERP)]、房室结前向和逆向传导有效不应期（ERP）、保持房室1：1传导的心房／心室起搏周长和心动过速周长。结果：3组患消融后AHmax(WCL)和AHmax（ERP）均明显短于消融前（P＜0．01）。B组和C组的消融后房室结前向ERP明显增加,而组无明显变化。A组消融前AHmax和房室结逆向ERP、消融后AHmax下降程度以及心动过速周长均小于B组和C组患。结论：伴连续房室结功能曲线的AVNRT患,心房刺激可表现或不表现房室结双径路的电生理特性,射频消融后心房刺激时AHmax明显缩短提示已成功根治了AVNRT。     

伴连续性房室结功能曲线的房室结折返性心动过速的电生理分析

目的：探讨无房室结双径路特性的房室结折返性心动过速(AVNRT)的电生理特点。方法：所有心动过速患射频消融前常规行心内电生理检查。结果：845例射频病人中325例为AVNRT，其中有21例患房室结功能曲线呈连续性，其电生理特征：希氏束图上心房回波(A)先出现，A波落在室波升支或其前，希氏柬不应期内刺激心室，不能提前夺获心房，射频消融后心房刺激时AHmax明显缩短。结论：伴连续性房室结功能曲线的AVNRT患心房刺激不表现房室结双径路的电生理特性，其消融终点初步定为：心房心室S1S1、S1S2刺激不诱发AVNRT；无AHvH传导曲线跳跃；房室结前传不应期明显缩短。     

房室结折返性心动过速患者房室结功能曲线连续性的电生理分析

分析房室结折返性心动过速 (AVNRT)中房室结功能曲线呈连续性者的电生理特点。将AVNRT分为房室结功能曲线连续组 (Ⅰ组 )及房室结功能曲线不连续组 (Ⅱ组 ) ,行慢径消融 ,进行消融前后和组间的电生理比较 ,分析房室结功能曲线呈连续性者的特点。结果 :I组心房程序刺激对AVNRT的诱发率仅 42 % (5 / 12 ) ,低于Ⅱ组的 6 6 %(2 3/ 35 )。Ⅰ组房室结前传有效不应期 (ERP AVN)消融前后无显著变化 (2 18.2± 2 9.3msvs 2 5 3.3± 80 .3ms,P >0 .0 5 ) ;心房程序刺激最长A2 H2 间期 (AHmax)消融前后无显著变化 (2 2 5 .8± 71.8msvs 175 .4± 41.9ms,P >0 .0 5 )。Ⅱ组ERP AVN消融后显著延长 (2 78.9± 5 8.9msvs 2 35 .8± 39.6ms,P <0 .0 5 ) ;AHmax消融后显著缩短 (172 .0± 6 7.1msvs 331.6± 86 .6ms ,P <0 .0 5 ) ;消融后房室结快径前传有效不应期 (ERP FP)显著缩短 (2 78.9± 5 8.9msvs 330 .0±5 5 .3ms,P <0 .0 5 )。消融前Ⅰ组AHmax短于Ⅱ组 (P <0 .0 5 ) ,Ⅰ组心动过速时A2 H2 间期 (AHSVT)与消融前AHmax比较差异无显著性 (P >0 .0 5 ) ;Ⅱ组AHSVT短于消融前AHmax(P <0 .0 5 )。结论 :房室结功能曲线连续性者较难经常规心房程序刺激诱发心动过速 ;慢径消融后曲线“尾巴”消失可作为消融终点的一项指     

房室结折返性心动过速的发作方式及射频消融终点研究

房室结折返性心动过速（AVNRT）是阵发性室上性心动过速（简称室上速）最常见的类型，约占阵发性室上速的50％。而房室结双径路（DAVNP）被认为是发生房室结折返性心动过速的基础。典型房室结折返性心动过速患者的房室结传导曲线（AVNFC）呈“跳跃”状态，然而，近年发现在AVNFC呈非跳跃性的患者也可发生AVNRT。可见房室结结构及其电生理特性极其复杂，本文对房室结折返性心动过速不同的发作方式及房室结传导曲线本质特点、射频消融治疗终点进行综述。     

房室结双径路“光滑”房室结功能曲线的本质探讨

目的 探讨房室结双径路“光滑”房室结功能曲线的本质。方法本组将房室结折返性心动过速(AVNRT)分成曲线光滑组(Ⅰ组)和曲线中断组(Ⅱ组)，井设立对照组，进行组间和消融前后的比较分析，观察房室结功能曲线的变化。结果 Ⅰ组术后房室结有效不应期(328±22ms)较术前(306±24ms)明显延长(P<0．05)．心房起搏时最长A2H2间期(205±65ms)较术前(280±51ms)明显缩短(p<0．01)；Ⅱ组术后房室结有效不应期(313±36n璩)也较术前(280±34ms)明显延长(p<0．01)，心房起搏时最长A2H2问期(180士38ms)亦较术前(322±39ms)明显缩短(p<0．01);消融前Ⅰ组最长A2Hz间期明显短于Ⅱ组(P<0．05)；消融前后两组房室结有效不应期差异不明显(p>0．05)。结论所谓“光滑”房室结功能曲线其实质也是由快径和慢径两部分组成，慢径消融可致曲线“尾巴”消失，这对AVNRT消融的终点判断具有指导意义。     

射频导管消融慢径路治疗程控刺激不能诱发且无明显跳跃的房室结折返性心动过速疗效分析

目的观察无A—H间期跳跃和不能诱发的房室结折返性心动过速（AVNRT）慢径路消融特点和远期疗效。方法经电生理检查证实无旁道参与的阵发性室上性心动过速患者100例,分成三组：能诱发AVNRT,有明显跳跃（A组,n=40）;不能诱发AVNRT,但有A—H间期〉50ms的明显跳跃（B组,1=40）;不能诱发AVNRT且没有A—H间期〉50ms的明显跳跃（C组．n=20）。比较术后各组电生理数值及消融远期疗效。结果与消融术前相比．术后各组患者的房室结顺传文氏周期均延长（P〈0．05）;消融术后房室结顺传有效不应期较术前缩短,差异有统计学意义（P〈0．05）;三组均出现缓慢交接区心律。术后随访12个月．各组复发率差异无统计学意义（P〉0．05）。结论无A—H间期跳跃且程控刺激不能诱发的AVNRT的慢径路消融是安全有效的。缓慢交接区心律是消融有效的标志。     

房室折返性心动过速合并房室结折返性心动过速的腔内电生理及射频消融特征二例

房室折返性心动过速(AVRT)病例中可发现有房室结双径现象(AVNDP),但并非都合并AVNRT,如果AVRT与AVNRT合并存在,不仅要消融旁路,还必须行房室结改良,方能根治室上性心动过速。本文报道2例AVRT合并AVNRT的电生理及射频消融特点。　　临床资料　例1　女性,48岁,因阵发心悸6年入院,发作心慌时,心率在160～190bpm。1997年1月28日在我院行射频消融术。心室频率递增刺激诱发阵发性室上性心动过速(PSVT),频率180～190bpm,标测为冠状窦远端(CSd)逆A领先。心房程序刺激,A2HA跳跃140ms,但未发作PSVT。大头电极至二尖瓣环下距冠状窦…     

刺激信号至QRS波起始与RR间期比值对房室结折返性心动过速患者慢径路的检测作用

目的 :评估保持 1∶1房室传导的最快心房刺激时 ,刺激信号至QRS波起始 (SR)与RR间期的比值 (SR/RR) ,对房室结折返性心动过速 (AVNRT)患者前传慢径路的诊断价值。方法 :将 12 7例患者分为两组 :①AVNRT组 79例〔按心房期前刺激时房室结前传曲线的特点又分为房室结前传曲线中断 (AH间期的跳跃值大于 5 0ms)者 5 6例和房室结前传曲线连续 (无AH间期的跳跃 )者 2 3例〕 ;②房室折返性心动过速组 (AVRT组 ) 48例。测量快速心房刺激时 (高位右心房 )的SR及RR间期 ,计算SR/RR比值。结果 :消融前 ,AVNRT组与AVRT组相比 ,其SR/RR比值相差较大 ,有显著性差异 (P≤ 0 0 5 ) ,消融后 ,AVNRT组的SR/RR比值变化较消融前为明显 (P≤ 0 0 1) ,而AVRT组较消融前则并无明显改变 ,两组间无差异 (P >0 0 5 )。SR/RR比值大于 1时 ,诊断慢径前传的特异性可达 91% ,敏感性为 81% ,阳性预测值为 90 % ,阴性预测值为 93%。结论 :快速心房起搏时能稳定保持 1∶1房室传导的最大SR/RR比值是显露房室结慢径前传的一个既简单又有效的可靠方法 ,对房室结前传曲线连续的典型AVNRT患者尤其有意义     

房室结折返性心动过速慢径消融终点与复发的关系

目的:观察房室结折返性心动过速(AVNRT)的慢径消融终点与复发的联系。方法:534个慢-快型AVNRT患者行慢径消融治疗,观察A型终点(彻底消融慢径,房室结无跳无折)和B型终点(残留慢径有或无1～3心房回波,不能诱发AVNRT)与AVNRT复发的联系及对房室结传导的影响。结果:①A型复发5例(1.2%),B型复发11例(9.4%),差异有统计学意义(P0.05)。②A型终点房室结前传文氏周期(Wen-AVN)、快径前传有效不应期和房室结双径路(DAVNP)的跳跃增值缩短,B型快径前传有效不应期和房室结双径路的跳跃增值缩短,A型有效不应期的缩短明显大于B型。结论:A型终点的复发率明显低于B型终点;只要改变房室传导功能,不能诱发心动过速,B型终点仍然是有效、可靠的消融终点。     

心房起搏时PR与RR间期比值对阵发性室上性心动过速鉴别诊断的意义

为探讨快速心房起搏最短１∶１房室传导时最大ＰＲ间期（ＰＲｍａｘ）与ＲＲ间期比值（ＰＲｍａｘ／ＲＲ）在鉴别阵发性室上性心动过速中的意义，分析比较了２０例房室结折返性心动过速（ＡＶＮＲＴ，有房室结前传跳跃现象者１２例、无跳跃现象者８例）和２０例房室折返性心动过速（ＡＶＲＴ）患者消融前、后快速心房起搏时最短１∶１房室传导的ＰＲｍａｘ／ＲＲ。ＡＶＮＲＴ组消融前、后心房快速起搏时最短１∶１房室传导的ＰＲｍａｘ／ＲＲ为１．１２±０．１２和０．４２±０．０７，两者比较差异有高度显著性，Ｐ＜０．０１；ＡＶＲＴ组为０．５２±０．１６和０．５１±０．１８，两者比较差异无显著性，Ｐ＞０．０５。消融前，ＡＶＮＲＴ组ＰＲｍａｘ／ＲＲ与ＡＶＲＴ组相比有显著性差异（１．１２±０．１２ｖｓ０．５２±０．１６，Ｐ＜０．０１）。ＰＲｍａｘ／ＲＲ＞１诊断ＡＶＮＲＴ的敏感性为９０％、特异性９１％。提示ＰＲｍａｘ／ＲＲ＞１在消融前可用来鉴别ＡＶＮＲＴ与ＡＶＲＴ；对无房室结前传跳跃的ＡＶＮＲＴ，消融后ＰＲｍａｘ／ＲＲ＜１可作为慢径消融成功的指标     

Cryoablation in pediatric atrioventricular nodal reentry: Electrophysiologic effects on atrioventricular nodal conduction

BACKGROUND: Cryoablation for treatment of atrioventricular nodal reentrant tachycardia (AVNRT) is safe and efficacious. Information on the effects of cryoablation on atrioventricular (AV) nodal conduction is limited. OBJECTIVES: The purpose of this study was to evaluate the effects of cryoablation on AV nodal conduction in pediatric patients with AVNRT. METHODS: We retrospectively analyzed electrophysiologic studies before and after successful cryoablation. Patients were divided into two groups: group 1 (n = 22, age 14 +/- 3 years) had baseline discontinuous atrial-to-His interval (AH) conduction curves; and group 2 (n = 13, age 12 +/- 4 years, P = .054) had continuous curves. RESULTS: At baseline, group 1 had longer measurements of maximal AH with A1A2, AV nodal effective refractory period, and AV block cycle length. Postcryoablation, both group 1 and group 2 showed decreases in maximal AH with A1A2 pacing or atrial overdrive pacing and in the finding of PR > or = RR with atrial overdrive pacing (group 1: 55% vs 5%, P < .001; group 2: 69% vs 0%, P < .001). A significant increase in overall AV effective refractory period and a decrease in AV block cycle length were found in group 1 but not group 2. Fifty percent of group 1 patients had complete abolition of slow pathway conduction. CONCLUSION: Successful cryoablation for treatment of AVNRT is associated with a reduction in PR > or = RR and with decreases in maximal AH with A1A2 pacing or atrial overdrive pacing. Further study is needed to determine the usefulness of these parameters for assessment of ablation efficacy or as proxies for AVNRT inducibility.     

快速心房起搏时SV间期与SS间期的比值在房室结折返性心动过速慢径消融中的应用

评价快速心房起搏时最快 1∶1房室传导的SV间期 (SV间期 )与 1∶1房室传导的最短S1S1间期 (SS间期 )的比值 (SV/SS)在房室结折返性心动过速 (AVNRT)慢径消融中的应用 ,将AVNRT分为房室结功能曲线连续组 (Ⅰ组 ,10例 )及房室结功能曲线不连续组 (Ⅱ组 ,17例 )测量心房分级递增刺激时的SS间期与SV间期及SV/SS ,并进行消融前、后和组间比较。结果显示 ,两组消融后SV间期较消融前明显缩短 (Ⅰ组 :2 2 1.0± 2 2 .3vs 35 7.0± 43.7ms;Ⅱ组 :2 0 2 .1± 30 .6vs 379.4± 44 .2ms,P均 <0 .0 5 ) ;消融前后SS间期无明显变化 (Ⅰ组 :310 .0± 40 .6vs 30 8.0± 36 .8ms;Ⅱ组 :332 .9± 48.1vs 336 .5± 6 2 .3ms) ;两组中所有患者消融前SV/SS比值均 >1,而消融后SV/SS比值均 <1。结论 :SV/SS可作为慢径消融成功终点的辅助观察指标之一 ,尤其对于房室结传导曲线呈连续性者 ,使用此方法可简便地观察消融终点 ,增加消融的目的性。     

Unique electrophysiologic characteristics of atrioventricular nodal reentrant tachycardia with different ventriculoatrial block patterns: Effects of slow pathway ablation and insights into the location of the reentrant circuit

BACKGROUND: The electrophysiologic mechanisms of different ventriculoatrial (VA) block patterns during atrioventricular nodal reentrant tachycardia (AVNRT) are poorly understood. OBJECTIVES: The purpose of this study was to characterize AVNRTs with different VA block patterns and to assess the effects of slow pathway ablation. METHODS: Electrophysiologic data from six AVNRT patients with different VA block patterns were reviewed. RESULTS: All AVNRTs were induced after a sudden AH "jump-up" with the earliest retrograde atrial activation at the right superoparaseptum. Different VA block patterns comprised Wenckebach His-atrial (HA) block (n = 4), 2:1 HA block (n = 1), and variable HA conduction times during fixed AVNRT cycle length (CL) (n = 1). Wenckebach HA block during AVNRT was preceded by gradual HA interval prolongation with fixed His-His (HH) interval and unchanged atrial activation sequence. AVNRT with 2:1 HA block was induced after slow pathway ablation for slow-slow AVNRT with 1:1 HA conduction, and earliest atrial activation shifted from right inferoparaseptum to superoparaseptum without change in AVNRT CL. The presence of a lower common pathway was suggested by a longer HA interval during ventricular pacing at AVNRT CL than during AVNRT (n = 5) or Wenckebach HA block during ventricular pacing at AVNRT CL (n = 1). In four patients, HA interval during ventricular pacing at AVNRT CL was unusually long (188 +/- 30 ms). Ablations at the right inferoparaseptum rendered AVNRT noninducible in 5 (83%) of 6 patients. CONCLUSION: Most AVNRTs with different VA block patterns were amenable to classic slow pathway ablation. The reentrant circuit could be contained within a functionally protected region around the AV node and posterior nodal extensions, and different VA block patterns resulted from variable conduction at tissues extrinsic to the reentrant circuit.     

快慢型房室结折返性心动过速的电生理特点

目的分析快慢型房室结折返性心动过速（AVNRT）患者的临床特征、心电网和电生理检查特点、射频消融治疗特点,旨在为临床长RP。心动过速鉴别提供帮助。方法11例经心内电生理检查证实为慢快型房室结折返性心动过速的患者,回顾性分析其临床特征、心电图特点及电生理检查特点及射频消融治疗。结果心动过速表现为窄QRs波心动过速,RP’〉P’R,P。在Ⅱ、Ⅲ、aVF导联倒置,RP’间期为350±25ms,心率为1664-30bpm。11例患者中有3例出现室房逆传跳跃现象。心房程序刺激无明显跳跃现象,11例均可由心房StS：刺激诱发心动过速发作,且容易诱发,容易终止。心动过速发作时,5例CS9．10A波最早,6例HiS的A波最早,其中1例静推ATP心动过速终止。11例患者中9例经房室结改良消融传统慢径获得成功,2例在冠状静脉窦内消融成功,术后随访3个月以上均未再发作心动过速。结论长RP’心动过速的诊断和鉴别诊断有一定困难,如能排除慢旁道和房速,应考虑快慢型房室结折返性心动过速。     

程控刺激不能诱发的房室结折返性心动过速慢径消融的临床疗效评估

目的　评价程控刺激不能诱发的房室结折返性心动过速 (AVNRT)射频消融慢径的临床疗效。方法　 6 1例有心动过速病史且心电图疑诊为AVNRT的病人 ,电生理检查有房室结双径(DAVNP)但不能诱发AVNRT ,随机分为两组。A组 30例不消融而进行临床随访 ,当心动过速复发且经心电图证实为窄QRS心动过速者接受射频消融阻断慢径。B组 31例接受射频消融以阻断慢径 ,术后临床随访。结果　A、B两组分别有 2 4例和 2 7例病人完成随访。A组 2 4例随访中分别在 1年内发作心动过速 ,再次接受消融阻断慢径后随访 (12 .1± 12 .2 )个月 ,仅 1例复发心动过速 (4.2 % ) ,与消融前比较差异有显著性 (P <0 .0 0 0 1)。B组 2 7例平均随访 (2 4 .2± 17.6 )个月 ,1例复发心动过速 (3.7% ) ,与A组病人消融前相比差异有显著性 (P <0 .0 0 0 1) ,而与其消融后比较差异无显著性 (P >0 .0 5 )。结论　有阵发性心动过速病史且心电图疑诊为AVNRT的病人 ,电生理检查有DAVNP而不能诱发心动过速者 ,射频消融阻断慢径具有良好的临床疗效。     

Characterizing dual atrioventricular nodal physiology in pediatric patients with atrioventricular nodal reentrant tachycardia

INTRODUCTION: Dual atrioventricular (AV) nodal physiology, defined as an AH jump > or =50 msec with a 10 msec decrease in A1A2, is the substrate for atrioventricular nodal reentrant tachycardia (AVNRT) and yet it is present in a minority of pediatric patients with AVNRT. Our objective was to characterize dual AV nodal physiology as it pertains to a pediatric population. METHODS/RESULTS: We retrospectively reviewed invasive electrophysiology studies in 92 patients with AVNRT (age12.1 +/- 3.7 yrs) and in 46 controls without AVNRT (age 13.3 +/- 3.7 yrs). Diagnoses in controls: syncope (N = 31), palpitations (N = 6), atrial flutter (N = 3), history of atrial tachycardia with no inducible arrhythmia (N = 3), and ventricular tachycardia (N = 3). General anesthesia was used in 49% of AVNRT and 52% of controls, P = 0.86. There were no differences in PR, AH, HV, or AV block cycle length. With A1A2 atrial stimulation, AVNRT patients had a significantly longer maximum AH achieved (324 +/- 104 msec vs 255 +/- 67 msec, P = 0.001), and a shorter AVNERP (276 +/- 49 msec vs 313 +/- 68 msec P = 0.0005). An AH jump > or =50 msec was found in 42% of AVNRT versus 30% of controls (P = 0.2). Using a ROC graph we found that an AH jump of any size is a poor predictor of AVNRT. With atrial overdrive pacing, PR > or = RR was seen more commonly in AVNRT versus controls, (55/91(60%) vs 6/46 (13%) P = 0.000). CONCLUSIONS: Neither the common definition of dual AV nodes or redefining an AH jump as some value <50 msec are reliable methods to define dual AV nodes or to predict AVNRT in pediatric patients. PR > or = RR is a relatively good predictor of AVNRT.