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。     

消融房室结慢径路导致窦性心律时的长PR间期恢复正常

房室结折返性心动过速(AVNRT)是以房室结双径路为基础的折返性室上性心动过速。大多数患者窦性心律时体表心电图的PR间期在正常范围。本文报道1例消融术前窦性心律时伴长PR间期的AVNRT患者，消融房室结慢径路后PR间期恢复正常。     

伴RR间期交替的室上性心动过速的射频消融

目的:探讨伴RR间期交替的窄QRS波心动过速的电生理机制和射频消融策略.方法:10例伴RR间期交替的心动过速患者接受了电生理检查,明确其心动过速类型后,首先消融旁路或诱发的心动过速,如仍能诱发房室结折返性心动过速(AVNRT)则消融慢径路,并随访了解心动过速复发情况.结果:10例患者中9例为左侧游离壁旁路合并房室结双径路,消融旁路后3例诱发AVNRT,一并成功消融了慢径路,另6例没有诱发AVNRT者未再消融,1例为房室结三径路,成功消融了慢径路.在6个月～8.4年随访中,无心动过速复发.结论:伴RR间期交替的心动过速具共同特点,即存在房室结双径路.在消融基础心动过速后,如不能诱发AVNRT,可不消融慢径路.     

射频导管消融后迟发性房室传导阻滞2例

例1 患者男性,46岁.因反复阵发性室上性心动过速入院行射频导管消融术.采用成都锦江通用电子仪器厂产LEAD-200A型电生理仪和HL-750型射频消融仪.术中电生理检查以冠状静脉窦电极作程序刺激,出现跳跃现象,快径路不应期340ms,慢径路不应期250ms,并诱发出阵发性室上性心动过速,诊断为房室结双径路.电视透视下,A-V间期以冠状静脉窦口处最近,术中置入大头电极于右心房,于冠状静脉窦口至三尖瓣环口间偏上小A波大V波处行射频导管消融,功率20W.消融7s后房室交接区心律及窦性心律交替出现.消融120s后,     

慢径消融对快径正传有效不应期及房室传导时间的影响

目的研究房室结双径路折返性室上性心动过速慢径消融对快径正传有效不应期及房室传导时间的影响。方法83例房室结内折返性心动过速（AVNRT）者根据消融前HRAS,S2扫描刺激时房室跳跃值的不同分为：A组：〈50ms;B组：50—80ms;C组：〉81ms。行慢径消融,消融后均无慢径残留,测量消融前后快径有效不应期、房室传导时间的变化。结果消融后快径有效不应期及房宣传导时间均较消融前缩短,差异有统计学意义（P〈0．05）。消融前HRA程序刺激时房室跳跃值越大,消融后快径有效不应期缩短越明显,差异有统计学意义（P〈0．05）;房宣传导时间亦有类似结果。结论慢径消融后快径有效不应期及房宣传导时间均缩短,提示慢径消融可改善快径前向传导功能。     

房室旁道合并房室结双径路的电生理特征四例

71临床资料倒三女性、4z岁。因阵发性心悸9年入院，院外心电图示室上性心动过速（SVT）。心内电生理检查及射频消融结果：①冠状静脉窦（＊S）S；不刺激（步长一IOms），sl＆300ms时出现人V。跃增120ms，并诱发SVT，心率14obpm，VA间期＜70ms，His京电极A波最提前，提示房室结双径路所致的房室结折返性心动过速（AVNRT）。反复多种程序刻激只能诱发AVNRT。②塞律时，消融电极于HIS束与CS口（CSO）之间消融，消融过程中交界性心律和窦律交替出现。消四后重复①的程序刺激，AV间期跃增现象消失，且不能诱发SVT。③右室15opp：…     

怀疑AVNRT患者的经验性导管消融

目的探讨经验性慢径导管消融治疗临床疑似房室结折返性心动过速(AVNRT)的可行性。方法回顾分析本院1998年10月~2015年10月368例接受房室结慢径消融治疗患者的临床资料、电生理检查与导管射频消融治疗结果及随访结果,比较323例电生理检查证实存在房室结双径传导且能诱发AVNRT和45例存在房室结双径传导但不能诱发AVNRT患者的消融结果及平均7.8年随访期内心动过速复发率,另对21例疑似AVNRT但电生理检查无房室结双径传导,无可诱发心动过速,且未接受慢径消融治疗的患者进行了平均1.4年随访。结果经导管射频消融术中不能诱发AVNRT患者与术中能诱发心动过速患者首次慢径消融的成功率均为100%,且均无严重并发症发生;术中不能诱发心动过速患者随访期心动过速复发率(4.4%)高于术中能诱发AVNRT患者(1.5%)(p0.05%)。术中能诱发AVNRT患者消融后复发病例均为首次消融时未达到主要消融终点(A-H间期跳跃现象消失)者,术中未诱发心动过速患者消融后复发病例再次电生理检查时均未发现存在房室结双径传导现象,亦未再诱发心动过速。在平均1.4年随访期内38%的疑似AVNRT但未接受经验性慢径消融治疗的患者再次发生心动过速。结论对于电生理检查证实存在房室结双径传导但不能诱发心动过速的疑似AVNRT患者,经验性慢径导管消融治疗安全有效,但应尽量以A-H间期跳跃现象消失作为消融终点。对于电生理检查未证实存在房室结双径传导,且不能诱发心动过速的疑似AVNRT患者,应酌情选择经验性慢径导管消融治疗。     

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。     

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。     

房室结折返性心动过速诱发特点的观察

76例房室结折返性心动过速（AVNRT）患者中,55例采用一般程序刺激可诱发室上性心动过速（SVT）,消融后观察30min,心内电生理不能诱发;21例采用一般程序刺激不能诱发SVT,静滴异丙肾上腺素后能诱发SVT,消融后观察30min,静滴异丙肾上腺素后,再重复心内电生理仍无SVT发生.两组消融复发率无统计学意义;但一般刺激诱发组快慢径路之间有效不应期（ERP）有统计学差异;应用异丙肾上腺素后刺激诱发组基础快慢径ERP无统计学差异.程序刺激是否诱发AVNRT,与患者的房室结前传功能有关,即快慢径路前向传导的ERP相差越大,则越易发生AVNRT.消融中如一般刺激不能诱发,可静滴异丙肾上腺素后再行程序刺激诱发,这对判断消融成功终点及减少复发有较大意义.     

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     

Atrioventricular nodal reentry tachycardia in children: curative treatment by high frequency catheter ablation

BACKGROUND: Atrioventricular nodal reentrant tachycardia (AVNRT) is one of the most common forms of supraventricular tachycardia in the pediatric population. PATIENTS AND METHODS: 41 children with a mean age of 9.6 (3.7-16) years with recurrent atrioventricular nodal reentrant tachycardia (AVNRT) refractory to medical treatment (n = 38) and recurrent syncope (n = 3) underwent electrophysiologic (EP) study. In all patients dual AV-nodal physiology could be demonstrated during EP study and typical form of AVNRT (mean heart rate 220/min) could be induced by programmed atrial stimulation. A steerable 7 F ablation catheter was placed at the inferoparaseptal region of the tricuspid valve annulus close to the orifice of the coronary sinus with the intention to record a late fractionated local atrial electrogram during sinus rhythm. Starting at this point radiofrequency current (500 kHz) with a target temperature of 70 degrees C was delivered with the intention to ablate the slow pathway. If a slowly accelerated junctional rhythm (< 120/min) occurred during energy discharge, programmed atrial stimulation was repeated. Otherwise radiofrequency current was delivered step by step up to a septal position next to the tricuspid valve annulus. Slow pathway ablation was defined as lack of evidence of dual AV nodal pathways during repeated atrial stimulation. Slow pathway modulation was defined as maximal one atrial echoimpulse after ablation. RESULTS: The number of energy applications ranged from 1-19 (median 6). In 35/41 patients slow pathway ablation could be achieved; in six patients the slow pathway was modulated. In none of the patients permanent high grade AV block was observed. During follow-up (mean 4.1 years) two patients had a recurrent episode of AVNRT after slow pathway modulation. All other patients are still free of AVNRT without medical treatment. CONCLUSION: Selective radiofrequency current ablation/modulation of the slow pathway is a safe and curative treatment of AVNRT in young patients.     

Unmasking of a concealed slow pathway by atrioventricular simultaneous basic pacing

A 71-year-old woman with narrow QRS tachycardia was referred for catheter ablation. The clinical tachycardia was diagnosed as slow/fast form of atrioventricular (AV) nodal reentrant tachycardia (AVNRT) with the upper common pathway. Although neither conventional nor double atrial programmed extrastimulation (APS) showed any evidence of a dual AV nodal pathway, AV simultaneous pacing during basic stimulation preceding APS (AVSP-APS) reproducibly revealed a dual AV nodal pathway as a double ventricular response. The AVSP-APS pacing method may be helpful to unmask a “concealed slow pathway” in patients with AVNRT.     

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。     

Long-term results of slow pathway ablation in patients with atrioventricular nodal reentrant tachycardia: simple approach

AimsThe aim of this study was to report the short- and long-term results of slow pathway radiofrequency (RF) ablation in patients with atrioventricular (AV) nodal reentrant tachycardia (AVNRT) using a simplified approach (2 catheters and short applications of RF).Materials and MethodsThis was a retrospective study that included consecutive patients with AVNRT. We used an anatomical approach with only 2 catheters. Decremental AV nodal conduction and atrial-His conduction interval jump were measured. To detect the onset of the QRS, we used surface lead II. During the stimulation protocol, we performed S2-QRS and S3-QRS measurements. An increase in the S3-QRS3 interval of 50 milliseconds or greater in response to a decrease in the S2-QRS2 coupling interval of 10 milliseconds was defined as a discontinuous AV nodal function curve and taken as evidence of dual antegrade AV pathways. Atrioventricular nodal reentrant tachycardia was demonstrated by the presence of dual AV nodal physiology, atrial echoes, and tachycardia induction with a 1:1 AV relationship and a VA interval of less than 70 milliseconds. Short RF applications (10-15 seconds) were delivered at an intermediate point between the posteroseptal and medioseptal regions of the Koch triangle. The applications were considered effective when junctional rhythm appeared. The end point was the demonstration of slow pathway modification without AVNRT induction.ResultsThree hundred forty-four patients (age, 49.22 ± 17.47 years; 254 were female) were included. Discontinuous AV nodal function curves were found in 271 patients (78.77%), and short-term success was achieved in all patients. The anterograde jump in AV nodal conduction was abolished after RF in 222 patients (81.91%), and discontinuous AV nodal conduction and single AV nodal echo beats persisted in 49 cases (18%). The mean number of RF application was 7.79 ± 2.23, the mean number of effective applications was 4.63 ± 0.62, and the mean RF application time was 54.92 ± 8.03 seconds. The total procedure and fluoroscopy time was 29.45 ± 9.6 and 10.87 ± 2.36 minutes, respectively. After the procedure, all patients were followed up for a mean of 46.44 ± 18.89 months, and 7 patients (2%) presented AVNRT recurrences. Complications were observed in 4 patients (1.16%); no permanent AV block was observed.ConclusionIn this study, slow pathway RF ablation using a simplified approach technique is an effective and safe approach for the treatment of AVNRT.     

从慢径消融发生的交界区心律试探房室结双径的本质

７６例慢－快型房室结折返性心动过速（ＡＶＮＲＴ）患者接受房室结慢径消融术。６５例慢径阻断、９例双径存在但ＡＶＮＲＴ不能诱发、２例快径阻断。慢径阻断后，除快径的前传有效不应期（ＥＲＰ）缩短（２８７．０±７９．０ｍｓｖｓ３４４．０±８７．０ｍｓ，Ｐ＜０．０１）外，房室传导的文氏点、２１阻滞点、室房传导的１１点、快径逆传ＥＲＰ、前传和逆传功能不应期均无明显改变。共放电８４１次，其中无交界区心律的３１７次放电，无一次消融成功。６５例慢径阻断者，交界区心律减少或消失。以上结果提示快径和慢径可能是两条各具电生理特性的传导纤维。     

Cryoablation for AVNRT: importance of ablation endpoint criteria

Cryoablation for AVNRT . Background: For ablation of atrioventricular nodal reentrant tachycardia (AVNRT), cryoablation has been shown to be a safe alternative to radiofrequency ablation. However, previous studies have shown a higher recurrence rate with cryoablation compared to radiofrequency ablation. Objective: This study reviewed our experience using cryoablation for typical AVNRT using stringent endpoint criteria for slow pathway ablation, yet preserving the desirable safety profile of cryoablation. Methods: Seventy‐five consecutive cases of typical AVNRT underwent cryoablation. Ablation of the AV nodal slow pathway was performed with the goal of eliminating tachycardia, AH jump, and retrograde atrial echo beats. The primary efficacy endpoint was freedom of recurrent supraventricular tachycardia at follow‐up. Analysis of AVN characteristics, number of lesions, and complications was performed. Results: Seventy‐two (96%) patients met the primary efficacy endpoint over an average follow‐up of 34.6 (12.6–68.3) months. In patients who had complete elimination of the slow pathway, there were no recurrences. The presence of an AH jump with a single retrograde echo was highly associated with a recurrence (P = 0.0001). There were no complications, including AV conduction block. Conclusion: The efficacy of cryoablation for management of AVNRT can be comparable to radiofrequency energy if the suggested endpoint of elimination of tachycardia, AH jump with retrograde atrial beats, is met. Prior studies evaluating cryoablation in this setting did not require this endpoint, which could have contributed to the relatively higher rate of late recurrences. (J Cardiovasc Electrophysiol, Vol. 23, pp. 729‐734, July 2012)     

Junctional rhythm occurring during AV nodal reentrant tachycardia ablation,is it different among Egyptians?

IntroductionRadio frequency ablation of the slow pathway has become first-line therapy for the elimination of AV nodal reentrant tachycardia (AVNRT). Slow pathway ablation is guided by a combination of fluoroscopic landmarks, electrogram morphology, and the induction of accelerated junctional rhythm (JR) during the application of radiofrequency energy. Although JR occurs usually during slow pathway ablation of AVNRT, the pattern of JR has not been adequately studied.¹³Aim of the studyTo investigate in detail the characteristics of junctional rhythm occurring during radiofrequency ablation of atrioventricular nodal reentrant tachycardia AVNRT among Egyptians.MethodsThis study included 30 patients who underwent electrophysiological study for narrow complex supraventricular regular tachycardia which revealed to be AVNRT.ResultsThirty (100%) patients showed induction of junctional rhythm at the successful ablation sites. JR was a very sensitive predictor of successful ablation but not so specific with specificity of 60%. Sex patterns of JR were observed. The most common pattern of JR was sinus–junctional–junctional (SJJ) while sinus–junctional-block (SJB) was the least. The most specific pattern for effective ablation was junctional–junctional–junctional (JJJ), while intermittent burst was the least. P value is 0.001 i.e. highly significant.ConclusionJunctional rhythm is a sensitive predictor of successful ablation. The pattern of JR is a useful predictor of successful ablation. Egyptian population has distinctive patterns of JR during AVNRT ablation.     

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。     

The response of the slow atrioventricular nodal pathway to temperature.

The present study attempted to determine the lowest temperature at which the slow atrioventricular nodal pathway responds to heating and the temperature necessary for successful ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia (AVNRT). The study group comprised 23 consecutive patients (14 women, 9 men) with symptomatic AVNRT. Radiofrequency current was delivered at the slow pathway potential recording site using a HAT 200S catheter ablation system. Successful radiofrequency ablation of the slow pathway was achieved in all 23 patients. Junctional beats, suggesting the response of the slow pathway to temperature, were detected in 62 of the total 136 applications. The temperature measured at the first junctional beat was 45.4+/-4.2 degrees C. The maximum temperature required for the successful ablation of AVNRT ranged from 45 to 88 degrees C. There were no complications except for 1 patient with transient atrioventricular (AV) block. There were no recurrences of AVNRT during follow-up. The lowest temperature at which the slow pathway was responsive to heat was quite similar to that for accessory pathways or the AV junction. However, the temperature required for the successful ablation of AVNRT differed markedly among the patients.