不典型房室结折返性心动过速射频消融的疗效

不典型房室结折返性心动过速射频消融的疗效贾锋鹏，雷 寒，马康华，覃 数，罗素新，何 泉（400016 重庆，重庆医科大学附属第一医院心内科）摘要 目的探讨不典型房室结折返性心动过速（atrioventricular nodal reentrant tachycardia,AVNRT）与典型AVNRT在消融时交界性心律伴有室房传导阻滞发生率、消融成功率和复发率等方面有无差异。方法42例AVNRT患者根据电生理检查结果分为不典型AVNRT组（慢慢型14例，快慢型7例）与典型AVNRT组（21例，其年龄和性别与不典型AVNRT组相匹配）。2组患者均采用消融慢径的方法，以消融过程中出现交界性心律，消融后室上速不再被诱发作为消融成功终点。比较2组患者交界性心律伴有室房传导阻滞发生率、手术时间、X线曝光时间、消融次数、成功率、并发症发生率和复发率有无差异。结果2组患者术中诱发的室上性心动过速周长无差异（P0.05）；与典型AVNRT组相比，不典型AVNRT组室上速时H-A间期延长（155.9040.86）ms vs （32.6218.25）ms,P =0.01，A-H间期缩短（142.7678.46） ms vs (265.2943.67) ms,P =0.034。所有患者达消融成功终点。2组患者的手术时间、X线曝光时间、消融次数、并发症发生率无差异（P0.05）。典型和非典型AVNRT患者慢径消融过程中均出现交界性心率反应，不典型AVNRT组交界性心律伴有室房传导阻滞发生率显著高于典型AVNRT组（66.7% vs 9.5%,P0.05）,但无继发的房室传导阻滞发生。2组患者消融术后均无房室传导阻滞等并发症发生。随访(25.311.6)个月，不典型AVNRT组阵发性室上速的复发率高于典型AVNRT组（23.81% vs 4.76%,P0.05）。结论不典型AVNRT慢径消融安全有效。与典型AVNRT慢径消融相比，不典型AVNRT有效消融时，常出现交界性心律伴室房传导阻滞发生，但不提示房室传导阻滞。不典型AVNRT消融术后复发率相对较高。关键词房室结折返性心动过速；电生理学；导管消融，射频电流；中图法分类号 R541.7R454.1R540.4 文献标志码 A Effects of rRadiofrequency ablation intreats atypical atrioventricular nodal reentrant tachycardia: a retrospective study of 21 cases patients Jia Fengpengg, Lei Han, Ma Kanghua, Qin Shu, Luo Suxin, He Quan (Department of Cardiology, ; the First Affiliated Hospital, Chongqing Medical University, Chongqing, 400016, China) Abstract Objective To investigate whether the radiofrequency (RF) ablation has same efficiency on treatment of of the atypical atrioventricular nodal reentrant tachycardia (AVNRT) might be as same effective as of the typical AVNRT. Methods According to electrophysiological examination results , 21 cases of atypical AVNRT (including 14 cases of slow/slow type and 7 cases of fast/slow type) were found among 247 42identified AVNRT who underwent RF ablation from June 2006 to June 2009 in our department, and another patients were classified into 2 groups: atypical AVNRT（21 cases,slow/slow type 14 cases and fast/slow type 7 cases）, and 21 age- and gender-matched cases of typical AVNRT from this cohort served as control（21 cases,match atypical type in age and gender）. The junctional rhythm appeared when slow passway ablation was performed and successful RF ablation was established achieved when the supraventricular tachycardia was no longer inducible. The rate of ventriculoatrial (VA) block of junctional rhythm during slow passway ablation, numbers of ablation application, procedure time, X- ray exposure, complications, acute success rate and recurrent rate, were compared between atypical and typical AVNRT. Results There was no obvious difference in Tthe tachycardia cycle length between did not differ betweenthe two 2 groups (P0.05). The H-A interval during tachycardia in patients with atypical AVNRT was longer than that in control group patients with typical AVNRT(（155.9040.86）ms vs (32.6218.25) ms, P =0.001), but the A-H interval was shorter in the former than in the later (（142.7678.46） ms vs (265.2943.67) ms, P =0.014). All cases were successfully slow passway ablated. There wasere no significance between the 2two groups in numbers of ablation application, procedure time, X- ray exposure, complications, and acute success rate. Compared to the controltypical AVNRT group, the rate of ventriculoatrial (VA) block of junctional rhythm during slow passway ablation was higher (66.7% versus 9.5%, P p=0.02), but was not associated with the atrioventricular (AV) block. During the follow-up period of 25.311.6 months, the rate of recurrence in atypical AVNRT group was higher than that in controltypical AVNRT group (（23.81% vs 4.76%, PP0.05)）. Conclusions The sSlow passway ablation areis both effective and safe for atypical AVNRT as for typical AVNRT. Compared to typical AVNRT ablation , the rate of VA block of junctional rhythm during slow passway ablation is higher in atypical AVNRT , but has no relation to the AV block complication ,. the The rate of recurrence after ablation might be a little higher .Key words Atrioventricular atrioventricular nodal reentrant tachycardia; Electrophysiologyelectrophysiology; Catheter catheter ablation, radiofrequency current Correspongding author: Jia Fengpeng, Tel:86-23-89012010, E-mail:jiafengpeng72通信作者：贾锋鹏，电话：（023）89012010，E-mail:jiafengpeng72房室结折返性心动过速 (atrioventricular nodal reentrant tachycardia, AVNRT)是较常见的心律失常，经导管射频消融能够达到根治。因大多数AVNRT是通过慢径顺传，快径逆传形成折返环所致，称之为慢快型，属于典型的AVNRT。另外少数AVNRT是由快慢型或慢慢型折返环路引起，称之为不典型AVNRT1。典型AVNRT采用慢径消融的方法，消融终点明确，安全性和成功率均很高。因不典型AVNRT患者病例数较少，采用慢径消融的方法是否与典型AVNRT消融有同样疗效，目前研究较少。对我院近3年来AVNRT患者的射频消融结果进行分析，比较典型与不典型AVNRT在慢径消融时出现交界性心律反应、安全性、有效性和复发率等方面有无差异。1 资料与方法1.1 病例资料收集2006年6月至2009年6月在本科连续成功完成的247例AVNRT射频消融患者，根据电生理检查结果分为不典型和典型AVNRT组。不典型AVNRT组21例；典型AVNRT患者227例，选择其中年龄和性别与不典型AVNRT组匹配的21例作为典型AVNRT组。所有患者心动过速发作时有明显心悸，部分患者伴有胸闷或头晕，均无黑蒙和晕厥。2组患者心动过速病史、合并高血压、2型糖尿病和冠心病病史等无差异。1.2心内电生理检查患者签署心内电生理检查及射频消融治疗知情同意书,停用抗心律失常药物5个半衰期。局麻下穿刺左锁骨下静脉和右侧股静脉,将十极和四极电极导管分别送至冠状静脉窦、His束部位、高位右房和右室心尖部。依次行心室、心房的程序期前刺激和分级递增刺激,检查出房室传导的文氏点和12点，快径和慢径的有效不应期，跳跃现象的窗口并诱发心动过速。如未诱发心动过速,静滴异丙肾上腺素提高心率后重复前述电刺激方法直到成功诱发出室上速。反复上述刺激方法仍不能诱发心动过速则退出研究。1.3标测和消融成功诱发出室上速后，分别测出A-H间期（冠状窦近端心房A波到希氏束H波的间期）和H-A间期（希氏束H波到冠状窦近端心房A波的间期）。心动过速时进行希氏束不应期内刺激和心室拖带进行鉴别诊断，排除房性心动过速和房室折返性心动过速2。慢快型AVNRT表现为H-A间期70 ms，心动过速时最早逆行心房激动点位于希氏束下后方，接近Koch三角顶部。不典型AVNRT包括快慢型和慢慢型AVNRT，其心动过速时最早逆行心房激动点，均位于三尖瓣环与冠状静脉窦口之间或冠状静脉窦内。慢慢型AVNRT的A-H间期200 ms以上，A-H间期H-A间期，H-A间期变异较大。快慢型AVNRT的H-A间期A-H间期，A-H间期200 ms3。患者均在窦性心率下慢径消融，采用电解剖法，根据X线影像和局部双极心内电图结合确定消融靶点3。右前斜30和左前斜45投照体位作为参考,温控标测消融导管在三尖瓣环与冠状静脉窦口和窦内之间进行标测。有效的消融靶点表现为碎裂的小A波和大V波，放电15 s左右有交界性心律发生，放电过程中交界性心律逐渐减少。消融时功率设定20 W，温度55 ，消融时间60120 s。房室结前传跳跃现象消失，不能诱发室上速；或房室结前传跳跃现象不消失，但静滴异丙肾上腺素后不能诱发室上速，并且无新出现的度以上房室传导阻滞作为消融成功终点。1.4随访所有患者术后停服抗心律失常药物，出院后1、3个月各随访1次,出现心悸时及时随访，此后每半年门诊定期随访，必要时动态心电图检查。1.5统计学处理计量资料用xs表示,两组间比较采用t检验和Fisher直接计算概率法。2 结果2.1 2组患者电生理检查结果比较不典型AVNRT组与典型AVNRT组患者均成功诱发出室上速，且室上速的周长(336.0533.01)ms vs (327.7631.66)ms, P =0.41无统计学差异。不典型AVNRT组与典型AVNRT组相比，H-A间期明显明显延长（155.9040.86）ms vs （32.6218.25）ms,P =0.01，A-H间期缩短（142.7678.46）ms vs (265.2943.67)ms,P =0.034。不典型AVNRT组患者21例，其中14例为慢慢型，7例为快慢型。心动过速时最早逆行心房激动点，位于三尖瓣环与冠状静脉窦口之间有16例，5例位于冠状静脉窦内。典型AVNRT组患者21例，心动过速时最早逆行心房激动点均位于希氏束下后方，接近Koch三角顶部。2.2 2组患者消融结果比较不典型AVNRT组三尖瓣环与冠状静脉窦口之间成功消融14例，冠状静脉窦内成功消融5例，三尖瓣环与冠状静脉窦口线性成功消融2例。典型AVNRT组三尖瓣环与冠状静脉窦口之间成功消融18例，冠状静脉窦内消融成功3例。虽然两组患者有效消融靶点放电时均出现交界性心律，但不典型AVNRT组14例患者成功消融靶点表现为交界性心律伴有室房传导阻滞，其发生率为66.7%，但窦性心律时无房室传导阻滞；7例患者表现为交界性心律不伴有室房传导阻滞。典型AVNRT组19例患者成功消融时出现交界性心律不伴有室房传导阻滞；2例（9.5%）患者出现交界性心律伴有室房传导阻滞时发生房室传导阻滞，立即停止放电后恢复，标测到其他安全靶点后成功消融，消融时出现交界性心律但不伴有室房传导阻滞。患者均达消融成功终点，消融后无房室传导阻滞等并发症发生。2组患者手术时间、X线曝光时间、消融次数等无差异（表1）。2.3 2组患者消融术后随访情况2组患者随访（25.311.6）个月，不典型AVNRT组5例患者术后复发，典型AVNRT组1例复发，复发率2组间有统计学差异（23.81% vs 4.76%,P0.05）。复发的患者再次慢径消融均获成功，随访期内无复发。表1 不典型AVNRT组与典型AVNRT组消融结果比较组别n手术时间（min）X线曝光时间（min）消融次数（次）不典型AVNRT2187.6216.6611.333.544.291.79典型AVNRT2186.3319.0910.762.814.431.75P0.810.560.793 讨论研究发现90%以上的AVNRT患者慢径消融时出现交界性心律反应，可能是由房室结的延伸区域心肌细胞受到热损伤时自律性增高引起4。出现交界性心律尽管不是有效消融的特异指标，却是敏感指标。本研究显示，不典型AVNRT与典型AVNRT慢径成功消融时均出现交界性心律，在手术时间、X线曝光时间、消融次数、并发症发生率和早期成功率方面无差异，说明不典型AVRNT慢径消融同样安全有效。本研究同时也发现不典型AVNRT慢径消融出现交界性心律时，常出现室房传导阻滞，其发生率明显高于典型AVNRT，但与房室传导阻滞发生率无相关性。Lee等5报道15例不典型AVNRT患者慢径消融时，13例出现交界性心律伴有室房传导阻滞，其发生率为86.7%，但无房室传导阻滞发生。Heidbchel等6观察到67%的快慢型AVNRT和53%慢慢型AVNRT患者慢径消融时也出现类似现象。这些研究均证实与典型AVNRT不同，不典型AVNRT慢径消融时出现交界性心律伴室房传导阻滞，并不代表快径的受损，是有效消融的标志同时也是安全的。典型AVNRT 慢径有效消融时，出现交界性心律可通过快径逆传到心房，表现为VA间期短。当出现室房传导阻滞时，往往提示快径受到损伤，有发生房室传导阻滞的高度风险，需立即停止放电，文献7-9给予了证实。本研究中2例典型AVNRT患者慢径消融时出现了交界性心律伴室房传导阻滞，同时也发生了房室传导阻滞，立即停止放电后恢复正常，说明虽然不同类型AVNRT慢径消融产生的结果相同，但消融时伴有室房传导阻滞的反应却有很大的不同。不典型AVNRT包括快慢型和慢慢型两类，尽管其确切机制仍有争议，但目前的研究认识到他们有共同的电生理基质。除了快径路外，致密房室结分别向右下和左下延伸形成两条慢径路。右下延伸到三尖瓣环和冠状静脉窦口；左下延伸到冠状静脉窦内顶部和左后间隔，通常右下慢径路比左下慢径路传导时间长。慢慢型AVNRT是通过右下慢径路逆传，左下慢径路前传形成逆钟向折返环路；快慢型AVNRT则相反，利用这两条慢径形成顺钟向折返环路10。其机制类似于左室特发性室速11。房室结左下延伸发育较差或仅在少数人群中出现，这解释了不典型AVNRT少见的原因12。可见与以前对快慢型AVNRT的认识不同，快径路不参与折返环路的形成。本研究发现不典型AVNRT与典型AVNRT组相比，H-A间期明显延长，A-H间期缩短也支持这一观点。不典型AVNRT慢径消融时，出现交界性心律可以不通过快径逆传到心房，表现为室房传导阻滞的发生，但并不代表快径的受损，因此不会出现房室传导阻滞13,14。不典型AVNRT慢径消融复发率是否高于典型AVNRT，文献报道有差异15。本研究发现，不典型AVNRT组室上速的复发率高于典型AVNRT组，这可能与以下因素有关：不典型AVNRT组患者需要在冠状窦内慢径消融的比例较高，考虑到安全性以及患者疼痛反应较剧烈，因此放电的功率和时间受到影响；另外部分不典型AVNRT患者，慢径分布范围较广，需要三尖瓣环与冠状静脉窦口线性消融才能成功。本中心2例患者初次三尖瓣环与冠状静脉窦口线性消融时无三维标测系统辅助，消融线不连续引起术后复发；再次消融时在CARTO系统辅助下获得成功，随访期内无复发。AVNRT射频消融最严重的并发症是完全性房室传导阻滞，后果较严重。尽管不典型AVNRT放电消融时，出现交界性心律伴室房传导阻滞是安全和有效的，但仍然要引起足够重视。因此诊断一定要明确，另外出现交界性心律伴有室房传导阻滞时，要观察窦性心律时房室传导的变化，若无变化继续放电巩固。如无窦性心律出现可供参考，仍然要停止放电进行观察，避免出现完全性房室传导阻滞。参考文献:1Katritsis D G, Camm A J. 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