射频消融慢径治疗程控不能诱发且没有跳跃的房室结折返性心动过速

目的:评价射频消融慢径治疗程控不能诱发且没有跳跃的房室结折返性心动过速(AVNRT)患者的远期疗效,探讨其电生理机制.方法:临床证实的AVNRT患者101例,在电生理检查中18例程控不能诱发及没有跳跃(A组),19例程控不能诱发(B组),33例程控没有跳跃(C组),31例程控有跳跃并且能诱发(D组).比较各组电生理的情况及射频消融治疗的远期疗效.结果:术后随访(49.13±30.13)个月,C组1例于术后2个月复发,发生Ⅲ度房室传导阻滞而安装起搏器,D组1例于手术后7个月复发,A、B、C、D组的未复发率均差异无统计学意义(P＞0.05).A、B组与C、D组相比快径逆传功能相对较差,术前B组的快慢径不应期差值较D组小,各组有效消融后交界心律的发生率差异无统计学意义.结论:慢径消融在治疗程控不能诱发及没有跳跃的AVNRT患者是安全有效的.交界性心律可以作为该类患者的射频消融的参考终点.     

射频消融房室结慢径时有效靶点的分布

通过分析120例房室结折返性心动过速的心内电生理和射频消融资料，发现消融成功的116例中，6例（5．1％）有效消融靶点位于希氏束与冠状窦口连线的前1／3段（A区），88例（75．9％）位于中1／3段（M区），22例（19．0％）位于后1／3段（P区）。2例在A区放电时发生完全性房室传导阻滞，另2例消融慢径失败。提示，房室结慢径消融的有效靶点75.9％分布于M区，慢径改良时应首选M区作为放电靶点，这有望提高成功率减少严重并发症。     

房室结折返性心动过速慢径改良术中靶点定位的方法学进展

房室结折返性心动过速(AVNRT)是一种常见的室上性心动过速,射频消融术(RFCA)是首选的治疗方法,从快径消融到慢径改良,随着成功率的提高,并发症的减少,RFCA治疗AVNRT的地位得到了进一步的确立。目前,RFCA治疗AVNRT的成功率可以达到98.8%,并发症的发生率在0.8%左右〔1〕。准确、有效的靶点选择是整个治疗过程的关键,它不但能增加治疗成功率、减少X线曝光时间及消融放电时间,而且能减少并发症的发生。现就慢径消融的靶点定位的方法学进展综述如下。1房室结双径路的解剖房室结双径路被认为是AVNRT的解剖基础〔2〕。Scherf于1926年…     

A波延迟电位在慢径消融靶点定位中的应用

为了探讨A波延迟电位在慢径消融靶点定位中的应用价值 ,对传统下位法和A波延迟电位引导下的慢径消融两组病例的靶点的电生理特征进行了研究。结果 :延迟电位引导下的慢径消融在提高成功率、减少试放电方面明显优于下位法。有效靶点的突出特征是A波宽度 >6 8ms、A波终末具延迟电位 ,A/V比例不能作为预测靶点的指标。A波延迟电位有四种形态 ,分别为单弓状延迟电位、双弓状延迟电位、穗状电位及A波终末的高频电位 ,其中以前两种最为常见。当程序刺激遇快径不应期而经慢径传导时 ,靶点正传的A波更加延迟 ,逆传A波更加领先是成功靶点的特征。结论 :在慢径消融的靶点定位中应用A波延迟电位和程序刺激可提高成功率、减少盲目性 ,A波延迟电位引导慢径消融方法优于传统的消融方法慢径消融方法优于传统的消融方法     

超速阈下刺激终止房室结折返性心动过速的位点与慢径消？…

目的 根据影像法射频消融房室结慢径是一相对盲目的方法,其单次放电的成功率低,导致房室阻滞的危险性高。本研究比较超速阈下刺激（ＵＳＳ）终止房室结折返性心动过速（ＡＶＮＲＴ）的位点与慢径消融靶点之间的关系,探讨ＵＳＳ是否可作为标测慢径的电生理指标。方法 选择ＡＶＮＲＴ患者１６例,所有患者均诱发出持续性ＡＶＮＲＴ,平均心动周期为（３３３．３１±４３．９）ｍｓ。按影像法结合腔内心电图从右后间隔冠状静脉窦口     

射频消融慢径对房室结双径路患者房室结传导功能的影响

目的 初步探讨房室结双径路是的电生理联系,方法 对３９例（男１３例,女２６例）平均年龄（４６．６±１６．４）岁的房室结哲返性心动过速患进行房室结慢径消融,观察慢径消融对房室结传导功能的影响。结果 成功率１００％,２６例消融后慢径消失（Ⅱ组）１３例消融后慢径残存（Ⅱ组）,消融前后Ｉ组房室结快径前传有效不应期由（３３２．５±４９．５）ｍｓ缩短为（２８２．５±５８．０）ｍｓ前传功能不应期由（３８２．９     

阈下刺激终止室上性心动过速有助于旁路消融靶点的定位

房室折返性心动过速(AVRT)的导管射频消融(RFCA)房室旁路已取得很好的疗效,其消融靶点定位大多以激动标测为主要方法,尽管成功率高,但需消融的次数较多,平均为3～8次。已有报道表明,近折返环的阈下刺激(sub-threshold stimulation,STS)能终止室性心动过速(VT)和左侧旁     

慢径电位特点及在射频消融房室结折返性心动过速中的临床应用

目的:在房室结双径路部分病例的心内电生理检查中发现存在提前于希氏束(HBE)电位的心房局部慢径电位(Asp),本文旨在探讨Asp出现的部位、电生理特点以及在消融慢径时的临床应用。方法:65例房室结折返性心动过速患者,比较以Asp为靶点消融(A组,n=20)和无Asp时传统方法慢径消融(B组,n=45)的功率、时间、放电次数和复发率。结果:22例(33.85%)描记到慢径电位共131个位点,主要位于M1～P1区(90.84%),较HBE提前(12.63±5.27)ms,AAsp间期(40.27±8.08)ms,AspV间期(61.90±11.55)ms,A组出现结区反应最小时消融功率(4.87±2.53)W,结区反应消失时消融功率(17.80±3.78)W,总消融时间(216.67±46.08)s,平均放电次数为(2.73±1.03)次,两组间有极显著性差异(P<0.01～0.001),所有病例未见房室传导阻滞发生。结论:房室结折返性心动过速患者Asp电生理指标不同于HBE,以Asp为靶点时,消融功率小、放电次数少、放电时间缩短,复发率下降,成功率提高。     

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。     

慢径路消融成功靶点的心内电图特征分析

目的 对慢径路消融时成功与不成功靶点的心内电图进行对比分析,以期揭示出成功靶点的心内电图特征。方法 常规电生理检查确诊为典型房室结折返性心动过速(AVNRT)患者87例,应用解剖和心内电图复合定位逐步自后间隔向中间隔方面进行慢径路消融,每一次放电后重复电生理检查直至慢径路消失或心动过速不能诱发为消融终点。分别记录每次放电前A波的时限、幅度、波峰数及相对落后于His束记录部位A波的间期、A/V比和慢径路电位。结果 所有病例均消融成功。平均放电次数(3.2±2.5)(中位数为3)。1例发生Ⅱ度Ⅱ型AVB,2个月后安置DDD永久起搏器。成功靶点与不成功靶点心内电图相比,A波时限较长[(67.5±10.3)ms vs(51.5±9.6)ms,P<0.01]波峰数较多[(2.9±0.8)vs(1.6±0.6),P<0.05]。单从A波时限分析,超过60ms对靶点成功消融的敏感性和特异性分别为86％和84％。慢径路电位在成功靶点发生率高(39％vs17％,P<0.01),对靶点成功消融的敏感性和特异性分别为51％和75％。结论 时限较长、碎裂的A波是消融成功靶点的心内电图特征性表现。慢径路电位在成功靶点发生率高,慢径路电位对靶点部位成功消融敏感性不高,不是靶点定位的必备条件。     

Temperature-controlled slow pathway ablation for treatment of atrioventricular nodal reentrant tachycardia using a combined anatomical and electrogram guided strategy

AIMS: Anatomical and electrogram-guided techniques have been usedseparately for slow pathway ablation in atrioventricular nodalreentrant tachycardia. The aims of the present study were toanalyse electrogram characteristics of target sites and biophysicalparameters using a combined anatomical and electrogram-guidedtechnique for temperature-controlled radiofrequency catheterablation of the slow pathway. METHODS AND RESULTS: Using a temperature-controlled (pre-selected 60 °C) cathetersystem, 53 patients with atrioventricular nodal reentrant tachycardiaunderwent slow pathway radiofrequency ablation. Mapping wasstarted posteroseptally near the coronary sinus ostium and continuedtowards the midseptal area if needed. The longest and latestatrial electrograms with an atrioventricular ratio of 0·5were targeted. After a median of two pulses (mean 2·36± 1·33), atrioventricular nodal reentrant tachycardiawas rendered non-inducible in all patients without complications.Successful sites had longer atrial electrograms (78·8± 9·8 vs 67·6 ± 13·3 ms,P<0·003) and larger ventricular electrogram amplitudes(92·4 ± 51·2 vs 63·1 ± 28·8mV, P<0·05) than the failed sites, but had a similaratrioventricular ratio, P-A interval and atrial electrogramamplitude. Overall, an atrial electrogram duration of 70 mswas associated with effective radiofrequency delivery, with86% sensitivity and 62% specificity. The achieved temperaturemaximum was 62·3 ± 9·8 °C at successfuland 58·8 ± 9·0 °C at unsuccessful sites(ns). There was no significant difference between successfuland unsuccessful applications with respect to power output,impedance and total delivery energy. During a pre-dischargestudy, three patients with inducible atrioventricular nodalreentrant tachycardia underwent a repeat ablation. During 12·3± 2·5 (6–15) months of follow-up, threeothers had a clinical recurrence of atrioventricular nodal reentranttachycardia. CONCLUSIONS: The combined approach for slow pathway ablation is highly effective,requiring a low number of radiofrequency pulses. Long atrialactivation time seems to be the most powerful predictor of success.Similar catheter tip temperature levels during successful andunsuccessful radiofrequency applications indicate that suboptimalselection of target sites rather than ineffective heating dueto poor catheter tissue coupling is responsible for unsuccessfulenergy delivery.     

Atrioventricular junctional reentrant tachycardia utilizing multiple retrograde fibers during ablation of the slow pathway

This report deals with a patient with atrioventricular (AV) reentrant junctional tachycardia who, during radiofrequency ablation of her slow pathway, developed both anterior and posterior type of slow-fast atrioventricular nodal reentry; in both tachycardias different fibers were alternately utilized for retrograde conduction, thus resulting in alternating tachycardia cycle lengths. This observation provides further evidence in favor of the multifiber structure of the AV node in patients with AV reentrant junctional tachycardia.     

中位法射频消蚀慢径路治疗房室结折返性心动过速

导管射频消蚀术（ＲＦＣＡ）治疗房室结折返性心动过速４３例，采用＂中位法＂选择性阻断慢径路，该技术的关键是：①在Ｘ线右前斜位３０度下，将消蚀电极置于冠状窦口和希氏束连线的中点附近；②消蚀电极双极记录到小Ａ大Ｖ波；③放电时有交界性心律（包括快交界律、慢交界律、交界性早搏）；④以间断放电和时间递增的方法控制消蚀过程；⑤消蚀终点为放电总累积时间达６０～９０秒，重复电生理检查证实慢径阻断或心动过速不能诱发。经１～３个部位的消蚀彻底阻断慢道３６例，遗留慢径传导７例（有心房回波２例）。除１例术后第二天发生一过性Ⅲ°ＡＶＢ，二周恢复正常外，余无并发症发生，随访３～２４个月（平均１４±６），停用任何抗心律失常药，无心动过速发作。消蚀成功率１００％。认为“中位法”是消蚀房室结慢径路治疗房室结折返性心动过速的安全、简便和有效的方法，部分病例保留慢传导并不增加复发率。     

Atrioventricular nodal reentrant tachycardia with ventriculoatrial block and unsuccessful ablation of the slow pathway

We report the case of failed slow pathway ablation in a woman with typical AV nodal reentrant tachycardia (AVNRT) and periods of Wenckebach-like second-degree VA block and 2:1 VA block. The occurrence of VA block during AVNRT suggests the upper turnaround point of the circuit is confined to the AV node. This supports the notion that, at least in some cases, the location of the reentrant circuit for AVNRT is completely in the compact AV node.     

选择性慢径路消融前后心脏电生理变化

目的 比较房室结折返性心动过速患者行选择性射频消融（RFCA）慢径路术前、术后心脏各部分腔内电生理改变.方法 对房室结折返性心动过速患者在选择性慢径路RFCA前、后分别进行腔内电生理检查.记录RFCA前、后希氏束电图（HIS）、心房有效不应期（A-ERP）、心室有效不应期（V-ERP）、房室前传文氏阻滞点（AVN-WKB）、室房逆传文氏阻滞点（VAN-WKB）、房室结前传有效不应期（AVN-ERP）和房室结逆传有效不应期（VAV-ERP）,将RFCA前、后心脏各部分电生理参数进行分析比较.结果 RFCA前、后HIS电图A-ERP、V-ERP、AVN-ERP及VAN-WKB差异均无统计学意义（P＞0.05）,AVN-WKB、VAN-ERP差异有统计学意义（P＜0.05）.结论 选择性RFCA慢径路对房室结双径路疗效肯定.在RFCA前、后（急性期）房室前传、逆传电生理均有一定改变.这与RFCA改变了房室结的部分结构,如大部分病例慢径路消失有关,不同消融部位对房室结传导电生理改变产生不同结果.     

Successful elimination of concealed accessory pathway-mediated tachycardia by ablation of AV nodal slow pathway

We report a case of atrioventricular reentrant tachycardia (AVRT) using a concealed para-Hisian accessory pathway for retrograde conduction, which also required anterograde conduction over the AV nodal slow pathway to maintain the tachycardia. The shortest VA interval during AVRT (70 ms) was noted at a site with His bundle electrogram amplitude of 0.25 mV. The AVRT was cured by radiofrequency ablation of the AV nodal slow pathway without affecting accessory pathway conduction. The patient has not reported any sustained palpitations at 2 years after ablation while receiving no medications. The case presented in this report illustrates a para-Hisian AVRT that was successfully eliminated by an unconventional approach of ablation of the atrial inputs to the AV nodal slow pathway.     

射频消融治疗房室结折返性心动过速不同终点的疗效观察

目的　评价射频消融治疗房室结折返性心动过速 ( AVNRT)的不同终点对远期复发的影响。方法　对 1 0 4例 AVNRT患者进行慢径消融 ,比较慢径传导消失组和慢径传导残留组 AVNRT复发率。结果　射频消融术后慢径传导消失 5 8例 ,慢径传导残留 4 6例 ,术后 1 8± 9个月随访期内 ,慢径传导消失组复发 2例 ( 3 .4 % ) ,慢径传导残留组复发 2例 ( 4.3 % ) ,两组无显著差别 ( P>0 .0 5 )。结论　射频消融术后慢径传导残留并不增加 AVNRT复发的危险性