关于房室结折返性心动过速慢径消融终点的探讨

534例慢-快型房室结折返性心动过速(AVNRT)患者行慢径消融治疗,观察A型终点(彻底消融慢径)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。A、B型分别复发5例(1.2%)、11例(9.4%),差异有统计学意义。B型终点的未复发与复发患者相比,其房室结前传文氏周期、快径前传有效不应期和房室结双径路的跳跃增值缩短。认为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。     

射频消融慢径后房室结电生理特性变化的探讨

目的:探讨房室结折返性心动过速(AVNRT)患者消融慢径对房室结电生理特性的影响。方法:①比较34例患者射频消融术前及术后AH间期、房室结前传及逆传文氏周期、快径路及慢径路前传有效不应期。②根据术后慢径是否消失将34例患者分为:慢径消失组(n=24);慢径改良组(n=10),比较两组间快径及慢径前传有效不应期。结果:房室结改良前后文氏周期变化:34例患者在未分组前射频消融前后房室结文氏周期无明显变化。快径前传有效不应期:慢径消失组快径前传有效不应期术后较术前降低,有显著性差异(P<0．05);慢径改良组慢径前传有效不应期术后较术前延长,有显著性差异(P<0．05)。结论:快径前传有效不应期的缩短与消融后慢径是否残存有关;慢径的消融影响房室结的前向传导。     

房室结快径电生理特性与慢径消融相互作用的临床研究

目的探讨房室结折返性心动过速慢径消融后对快径传导的影响。方法入选慢快型房室结折返性心动过速患者42例,根据首次放电消融后结果进行分组,第一组:慢径消失组:不能再诱发房室结折返性心动过速;第二组,慢径改良组:可见慢径跳跃现象;第三组:慢径残存组,可见慢径跳跃现象,或后可诱发房室结折返性心动过速。比较三组患者消融前后的快径不应期,快径前传时间,快径前传时间差值变化。结果慢径消失组17例(40.5%),慢径改良组14例(33.3%),慢径残存组11例(26.2%)。慢径消失组患者消融前后快径不应期缩短(234.71±13.28vs331.18±21.18,p0.05)差异存在统计学意义,慢径改良组患者消融后快径不应期缩短(245.71±12.22vs323.57±26.49,p0.05)差异有统计学意义,慢径残存组患者消融前后快径不应期无明显变化(264.55±21.62 vs320.91±15.78,p=0.23)。与慢径残存组相比,慢径消失组和慢径改良组传导消融术后快径不应期以及快径前传时间明显缩短,存在统计学差异。结论慢径完全消融后,快径不应期和快径前传时间均明显缩短,提示慢径消融的同时可以改善房室结快径的前向传导功能,这一现象可结合其他指标作为评价房室结折返性心动过速慢径消融效果的参考。     

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。     

射频消融慢径路对房室结快径路前传功能的影响

目的房室结折返性心动过速(AVNRT)是一种很常见的室上性心动过速.它的发生主要是因为房室结存在不应期和传导速度不同的径路:快径路和慢径路.射频消融慢径路治疗AVNRT可以取得很好的效果,但是慢径路被消融后对房室结快径路前传的影响还不十分清楚.我们的目的在于观察AVNRT患者慢径路被消融后对房室结快径路的影响.     

房室结慢径消融后对快径前传不应期影响

<正> 房室结双径路(DAVNP)是形成房室结折返性心动过速的必须电生理基础,射频消融房室结慢径路是治疗房室结折返性心动过速(AVNRT)安全、有效的方法.射频消融慢径路后有学者发现快径路前传不应期发生改变,本文对慢径路消融后快径路前传不应期改变,探讨慢径路消融后对快径路前传不应期的影响.1 资料和方法1.1 病例选择经电生理检查证实为DAVNP伴AVNRT患者44例,其中男性21例,女性23例;年龄15～77岁,平均年龄46.77±14.89岁;病史0.6～30年,均有反复发作室上性心动过速史.无器质性心脏病证据.合并房室结快径经消融者未选入.     

射频消融术中房室结快慢径前传不应期变化及其意义

探讨 2 7例房室结折返性心动过速 (AVNRT)病人射频消融术 (RFCA)中房室结前传有效不应期 (ERP)变化的意义 ,应用心房程序刺激法测定放电前后房室结快慢径前传ERP并据此指导治疗。结果 :2 7例AVNRT病人房室结ERP对射频电流呈 4种反应 :①快径前传ERP缩短 10例。其中 6例表现为引起跳跃的S2 间期缩短 ,无心房回波 ,异丙肾上腺素可诱发AVNRT ,继续寻找并消融慢径 ,跳跃现象消失。 4例前传ERP由 36 0± 15ms缩至 170± 8ms,跳跃消失 ,异丙肾上腺素不能诱发AVNRT ,不再消融。②快径前传ERP延长 6例 ,由 36 0± 10ms增至 430± 12ms。延长S2 与S1耦联间期行心房程序刺激 ,跳跃再现 ,继续寻找并消融慢径至跳跃消失。③慢径前传ERP缩短 5例。术中AVNRT频率由 170± 14次 /分增至 2 30± 11次 /分。继续消融慢径 ,跳跃消失。④慢径前传ERP延长 6例 ,表现为AVNRT的频率减慢 ,继续消融慢径获成功。上述病人经 3.3± 0 .8( 2 .0～ 4.5 )年的随访 ,未见房室阻滞 (AVB)发生 ,亦无AVNRT复发。结论 :对于少数AVNRT病人 ,借助术中房室结前传ERP的变化指导消融 ,可望提高治疗效率、减少复发机率、避免AVB的发生。     

房室结折返性心动过速慢径消融术后复发原因分析

目的探讨房室结折返性心动过速(AVNRT)导管射频电消融(RFCA)术后复发的原因。方法对行导管射频电消融术100例慢快型房室结折返性心动过速患者进行随访,回顾性分析其心电生理和临床资料。结果100例患者中复发10例,复发率为10%。复发病例中7例术后慢径残存,未复发病例中3例慢径残存,慢径残存患者复发率高。未复发病例消融后的快径前传有效不应期(FPERP)较消融前缩短,分别为(277±41)m s和(318±46)m s(P<0.05);而复发病例消融后的快径前传有效不应期(FPERP)较消融前无明显缩短,分别为(298±48)m s和(311±56)m s(P>0.05)。复发病例心内电生理特点复杂多变,多种类型房室结折返性心动过速多见,未复发病例多为单纯典型房室结折返性心动过速。结论房室结折返性心动过速复发的电生理基础仍然是房室结双径路,房室结折返性心动过速复发与慢径残存及复杂的房室结、慢径结构有关。     

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。     

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慢径消融终点与临床疗效关系探讨

62例慢-快型房室结折返性心动过速（AVNRT）患者接受慢径消融治疗,评价A型终点（阻断慢径且不再诱发AVNRT）、B型终点（保留慢径的传但不再诱发AVNRT和心房回波）和C型终点（保留慢径且能诱发1～3个心房回波）对房室传导功能的影响及与AVNT复发的关系。结果：①消融后77．4％（48例）;17．7％（11例）和4．8％（3例）的病人分别达A、B和C型终点;②消融后A型终点病人的房室传导功能明显改善,B、C型变化不明显;③术后3～7天经食管电生理复查,A型终点AVNRT的再诱发率为2．1％（1例）、B型为18．2％（2例）、C型为33．3％（1例）;④41例病人保持随访8．9±7．1个月,A型终点AVNRT复发率为4．9％,B、C型为28．6％。结果揭示AVNRT慢径消融中大多数病人可达到A型终点,且彻底阻断慢径后房室传导功能明显改善,AVNRT的近期和远期复发率明显低于B到和C型终点。     

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。     

Cryothermal slow pathway modification for atrioventricular nodal reentrant tachycardia.

AIMS: Predictors of recurrence following transcatheter cryoablation for atrioventricular nodal reentrant tachycardia (AVNRT) are currently unknown. Our objective was to explore predictors of recurrence post-cryoablation for AVNRT, including the impact of procedural endpoints such as complete elimination of slow pathway conduction vs. persistent dual atrioventricular (AV) nodal physiology with or without echo beats. METHODS AND RESULTS: A single center cohort study was performed on patients undergoing a first cryoablation procedure for AVNRT between May 1999 and December 2004. Cryoablation for AVNRT was attempted in 185 consecutive patients (79.2% female), age 43.1 +/- 15.2 years. Acute success was achieved in 170 (91.9%) patients with 4.4 +/- 3.5 cryoapplications and a total procedural duration of 2.8 +/- 0.8 h. Complete elimination of slow pathway conduction was noted in 47.6% of acutely successful interventions, absence of AV nodal echoes despite dual AV nodal physiology in 8.8%, and presence of echoes but no inducible AVNRT on and off isoproterenol in 43.5%. Actuarial recurrence-free survival following acutely successful cryoablation at 1, 3, 6, 12, and 24 months was 94.8, 93.1, 91.7, 90.8, and 90.8%, respectively. Independent predictors of recurrence were younger age (P = 0.0045) and valvular heart disease (P = 0.0186). The achieved procedural endpoint did not modulate recurrence rates. Eight patients (4.3%) experienced transient third degree AV block; none required permanent pacing. CONCLUSIONS: As a cryoablation procedural outcome for AVNRT, persistent dual AV nodal physiology with or without echo beats is not associated with higher recurrence rates than complete elimination of dual AV nodal physiology if AVNRT remains non-inducible on and off isoproterenol.     

Predictors of long-term success in catheter ablation of atrioventricular nodal reentrant tachycardia: a multivariate regression analysis

BACKGROUND: To investigate the predictors of long-term success after catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT). METHODS: One-hundred and fourteen consecutive patients underwent slow pathway ablation using anteroseptal (n=24), midseptal (n=65) and posteroseptal approach (n=25). The correlation between ablation approaches, electrophysiological characteristics during and after ablation and the recurrence rate of AVNRT was analyzed by a multivariate regression analysis. RESULTS: During ablation, transient AV block in the anteroseptal, midseptal and posteroseptal approach occurred in 8.3, 4.6 and 0%, respectively (P<0.01). AVNRT recurred in seven patients after 5 years follow-up. Five recurrences (20.8%) were from anteroseptal approach group and two (3.1%) were from midseptal approach group. Multivariate regression analysis revealed that anteroseptal ablation approach and residual dual atrioventricular nodal pathway following apparently successful ablation were the predictors for recurrence of AVNRT (R=0.645, P<0.001). CONCLUSION: Anteroseptal approach of slow pathway ablation is associated with a higher incidence of transient AV block and AVNRT recurrence than other approaches. Residual dual atrioventricular nodal pathway after apparently successful ablation also carries a high risk of recurrence.     

Atrial tachycardia with slow pathway conduction mimicking typical atrioventricular nodal reentrant tachycardia.

A 68-year-old woman with palpitations underwent electrophysiologic testing. During burst atrial pacing the PR interval exceeded the RR interval and induced a supraventricular tachycardia consistent with a typical AV nodal reentrant tachycardia (AVNRT). Radiofrequency ablation of the slow pathway during the tachycardia immediately produced 2 : 1 AV conduction. After slow AV nodal pathway ablation an atrial tachycardia (AT) remained inducible with the earliest atrial activation around the HB region. Radiofrequency ablation at the site of earliest atrial activation interrupted the AT without AV block. AT originating from the HB region with slow pathway conduction may mimic typical AVNRT.     

Percutaneous catheter modification of the atrioventricular node. A potential cure for atrioventricular nodal reentrant tachycardia

Our purpose was to describe a technique of atrioventricular (AV) node modification for patients with drug refractory AV nodal reentrant tachycardia (AVNRT). Nine patients (mean age, 45 +/- 20; range, 14-82) with recurrent drug refractory AVNRT (n = 8) or sudden cardiac death thought to be precipitated by AVNRT (n = 1) underwent a percutaneous catheter procedure to modify AV nodal function. The area between the electrode recording the maximal His-bundle electrogram and the ostium of the coronary sinus was divided into three zones. Perinodal direct current shocks of 100-300 J were delivered to one (n = 2), two (n = 3), or three (n = 4) zones without complications. The procedure endpoints were modification of AV conduction (either first degree AV block or complete retrograde ventriculo-atrial [VA] block) and failure to induce AVNRT before or after isoproterenol and/or atropine administration. Six of nine patients (67%) have had no inducible or spontaneous AVNRT over a mean follow-up of 12.3 +/- 4.1 months (range, 4.5-17). One of the six underwent repeat, successful modification, because AVNRT was inducible at restudy 2 days after the initial procedure. AVNRT recurred in three patients (33%), one early (3 days) and two late (3-4 months). Two of these patients underwent complete ablation of the AV junction and permanent pacemaker placement, whereas one is controlled with drug therapy. Therefore, AV nodal modification resulted in tachycardia control without antiarrhythmic drugs in six of nine (67%) and obviated the need for complete AV junctional ablation in seven of nine patients (78%). Elimination of AVNRT appears to result from either block in the retrograde fast pathway or modification of the antegrade slow pathway, such that AVNRT cannot be sustained. Additional findings suggest that an atrio-Hisian accessory connection may not be involved in AVNRT in some of these patients. Percutaneous catheter AV nodal modification appears to be a promising technique for treatment of refractory AVNRT and may obviate need for complete AV junctional ablation in a substantial number of patients with drug/pacemaker refractory AVNRT.     

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.     

非跳跃性房室结功能曲线的房室结折返性心动过速消融成功的电生理特点

目的 :探讨呈非跳跃性房室结功能曲线 (AVNFC)的房室结折返性心动过速 (AVNRT)射频消融成功的电生理特点。方法 :将 75例AVNRT患者分为 3组 :A组 16例 ,心房递增起搏和A1A2 程序刺激均呈非跳跃性AVNFC ;B组 10例 ,仅心房递增起搏呈跳跃性AVNFC ;C组 4 9例 ,心房递增起搏和A1A2 程序刺激均呈跳跃性AVNFC。比较 3组患者射频消融前后组内及组间的电生理参数。结果 :消融后 3组患者心房递增起搏时最大AH间期 (A1H1max)均比消融前显著缩短 (P <0 .0 5 )。A组消融前、后A1H1max的缩短程度均小于B组和C组 (P <0 .0 5 )。A组非典型AVNRT的诱发率明显高于B组和C组。结论 :对于心房递增起搏和A1A2 程序刺激均呈非跳跃性AVNFC的AVNRT患者 ,消融后A1H1max的显著缩短可作为消融成功的指标之一。AVNFC呈非跳跃性的房室结双径路患者易诱发非典型AVNRT。     

Radiofrequency catheter ablation of atrioventricular nodal reentrant tachycardia in children aided by the LocaLisa mapping system.

AIMS: In young patients, slow pathway ablation for treatment of atrioventricular nodal reentrant tachycardia (AVNRT) carries a small but definite risk of permanent AV block. The aim was to assess the efficacy of slow pathway ablation aided by the LocaLisa mapping system. PATIENTS AND METHODS: Radiofrequency (RF) modification of the slow AV nodal pathway was performed in 26 children < 19 years of age (median age 9.8 years, range 3-18.9). Three measures to limit the risk of AV block were applied: (1) use of LocaLisa, a non-fluoroscopic mapping system, to determine and mark the location of the AV node/His bundle axis, and monitor ablation catheter position, (2) continuous atrial stimulation during RF delivery to monitor AV conduction, and (3) gradual increase of RF power during RF ablation. RESULTS: AVNRT was rendered non-inducible in all patients. Dual AV physiology was abolished in 24/26 patients; 2 patients had single atrial echoes at the end of the procedure. At follow-up, AVNRT recurred in 3 patients (including the above 2), necessitating a second procedure. The median number of RF applications was 4 (3-8); median fluoroscopy time was 16 (7-33)min. One patient developed transient second-degree AV block, with full recovery within 6 weeks of the procedure. CONCLUSIONS: RF modification of the slow AV nodal pathway in children can be safely accomplished, achieving the ideal end-point of abolishing dual AV physiology, aided by use of the LocaLisa mapping system.     

射频消融治疗房室结折返性心动过速术后复发原因分析

目的 :探讨房室结折返性心动过速 (AVNRT)射频电消融 (RFCA)术后复发原因。方法 :对 2 0 2例A VNRT患者 RFCA术后进行随访 ,回顾性分析其电生理资料。结果 :2 0 2例中 12例复发 ,复发率 5 .9%。复发组7例 (5 8.3% )、非复发组 18例 (9.5 % )靶点数 <3,复发组 9例 (75 .0 % )、非复发组 17例 (8.9% )慢径残存 ,两组比较均差异有非常显著性意义 (P <0 .0 1) ,复发组 2例有明显的慢电位未加消融。结论 :消融靶点数 <3及慢径残存、慢电位靶点处未加消融是 RFCA治疗 AVNRT术后复发的主要原因。