房室结折返性心动过速射频消融术中特殊病例分析

在２６０例房室结折返性心动过速（ＡＶＮＲＴ）射频消融中出现１１例特殊病例。其中男３例、女８例。５例属电生理现象复杂，其中１例快－慢型者Ｓ１Ｓ１５００ｍｓ心室刺激时，连续３个刺激便出现室房文氏现象，随之出现心动过速，ＡＶＮＲＴ时心室率１８２ｂｐｍ，Ｈｉｓ束电极Ａ波最先激动，呈Ａ－Ｈ－Ｖ传导，ＶＡ间期２２０ｍｓ，ＶＡ＞ＡＶ；另１例快－慢型者心内电生理诱发出典型ＡＶＮＲＴ，其频率１６２ｂｐｍ，对其慢径改良后，诱发出另一种频率的快－慢型ＡＶＮＲＴ。３例慢－慢型者心动过速较易诱发，ＡＶＮＲＴ时均以冠状静脉窦口（ＣＳＯ）Ａ波最提前，Ｈｉｓ束电极示Ｈ－Ｖ－Ａ传导。３例永存左上腔静脉，ＣＳＯ异常扩张，窦口上缘几乎接近Ｈｉｓ束水平。３例放电过程特殊者，其中１例在较大范围内消融，均出现慢交界区心律，另１例在消融中出现一个交界区心律后，便诱发ＡＶＮＲＴ，再有１例为消融时难以出现慢交界律。所有病例均消融成功（１００％）。结果提示对特殊病例除应进行详细电生理检查之外，应采取不同的消融策略     

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     

射频消融慢径后心动过速复发与房室结电生理特性变化的关系

为揭示房室结折返性心动过速（ＡＶＮＲＴ）复发的机制，对４５例射频消融治疗成功的慢－快型ＡＶＮＲＴ患者在消融术前、术后即刻及术后逾三个月行电生理检查。结果１０例复发（复发组）。复发组术前心房早搏刺激时的最大心房－Ｈｉｓ束间期（Ａ２Ｈ２ｍａｘ）较非复发组明显延长（４１３±６０ｍｓｖｓ３１１±１１０ｍｓ，Ｐ＜０．０１）；两组术后即刻Ａ２Ｈ２ｍａｘ较术前均明显缩短（Ｐ均＜０．０１）；术后三个月复发组的Ａ２Ｈ２ｍａｘ较术后即刻明显延长（３５６±９３ｍｓｖｓ２９８±９６ｍｓ，Ｐ＜０．０５），非复发组则有进一步缩短趋势，两组术后三个月的Ａ２Ｈ２ｍａｘ比较有显著性差异（３５６±９３ｍｓｖｓ２２２±７３ｍｓ，Ｐ＜０．００５）；非复发组术后三个月Ａ２Ｈ２ｍａｘ较术前明显缩短（２２２±７３ｍｓｖｓ３１１±１１０ｍｓ，Ｐ＜０．０１），房室结前传文氏周期及有效不应期较术前明显延长（４０５±９１ｍｓｖｓ３６６±８４ｍｓ，３３２±７５ｍｓｖｓ２６９±６３ｍｓ，Ｐ＜０．０１及＜０．０００１），复发组消融术前后比较差异则无显著性。结果提示部分ＡＶＮＲＴ复发可能与其房室结本身电生理特性有关，基础状态下Ａ２Ｈ２ｍａｘ长的患者心动过速更易复发。     

房室结折返性心动过速与冠状静脉窦关系的初步 …

为探讨房室结双径路导致折返性心动过速的发病机制，以更准确的选择消融靶点和减少并发症。对经电生理检查诊断的３３例室上性心动过速病人进行冠状静脉穿造影的对比研究，分为两组，其中房室结折返性心动过速组１７例，对照组１６例。两组病人均经ＣＳ造影观察ＣＳ形态，走行分支情况，测量ＣＳ口大小，窦体直径，长度及窦口上缘与Ｈｉｓ束之间的距离。     

射频消融的临床应用

对２１例阵发性室上性心动过速（ＰＳＶＴ）患者施行导管射频消融（ＲＦＣＡ），其中１０例为预激综合征并房折返性心动过速（ＷＰＷ并ＡＶＲＴ），１０例为房室结双径路并房室结折返性心动过速（ＡＶＮＤＰ并ＡＶＮＲＴ），１例为房内折返性心动过速（ＩＡＲＴ）。经ＲＦＣＡ预激旁路和房室结改良有１８例获得成功，成功率８５．７％。无并发症，随访１～６个月未见复发者。     

心房起搏法在射频消融房室结折返性心动过速中的应用

将射频消融治疗的９４例房室结折返性心动过速（ＡＶＮＲＴ）病人按心房起搏法和常规法进行分组（分别为３９及５５例），回顾性比较两组病人的消融治疗结果，以评价这两种方法在射频消融治疗ＡＶＮＲＴ中的安全性、成功率和复发率。随访１０．８±４．５个月，总成功率为９６．８％、复发率为２．１％。与常规组相比，起搏组有效放电时间明显延长（１４５±３８ｓｖｓ８２±２６ｓ，Ｐ＜０．０１）、慢径阻断成功率高（６１．５％ｖｓ４０．０％，Ｐ＜０．０１）、一过性房室阻滞发生率低（２．６％ｖｓ１２．７％，Ｐ＜０．０５），但各种类型的永久性房室阻滞发生率和复发率无显著性差异（Ｐ＞０．０５）。表明ＡＶＮ－ＲＴ消融术中采用心房起搏法较常规法更为安全有效。     

PV1—PE值对不同部位房室旁束所致室上速的诊断意义

本文通过食管心房起搏与心内电生理对照研究６６例正向型房室折返性心动过速（ＯＡＶＲＴ）和慢－快型房室结折返性心动过速（ＡＶＮＲＴ）的ＰＶ１－ＰＥ时距。结果显示在绝大部分病例中，左侧不同部位游离壁旁束参与的ＯＡＶＲＴ，ＰＥ明显领先于ＰＶ１；右侧不同部位游离壁旁束参与的ＯＡＶＲＴ，ＰＶ１明显领先于ＰＥ；慢－快型ＡＶＮＲＴ时ＰＥ和ＰＶ１几乎同时出现；而当左侧旁束位于左前侧壁，右侧旁束位于右后侧壁，并伴有心房增大时，可不符合上述规律。ＰＶ１－ＰＥ绝对值２５ｍｓ可作为鉴别ＯＡＶＲＴ与ＡＶＮＲＴ的定量指标。     

隐匿性拖带时起搏后间期与慢径消融成功靶点 …

评价应用隐匿性拖带方法对准确靶点消融的有效性及探讨常规慢径靶点部位与房室结折返性心动过速（ＡＶＮＲＴ）折返环的关系。可反复诱发的持续性典型ＡＶＮＲＴ的患者３４例,消融导管在后或中间隔标测到Ａ／Ｖ≤０．５处,然后诱发心动过速,在高位右房（ＨＲＡ）和冠状窦口（ＣＳＯ）超速起搏产生隐匿性拖带,并按常规方法进行慢径消融。比较隐匿性拖带时靶点部位起搏后间期与心动过速周长的差值（ＰＰＩ－ＴＣＬ值）在成功靶点与     

射频导管消融治疗儿童室上性心动过速100例体会

经射频导管消融（ＲＦＣＡ）治疗３．５～１４岁儿童阵发性室上性心动过速（ＰＳＶＴ）１００例，探讨ＲＦＣＡ治疗儿童ＰＳＶＴ的安全性及疗效。１００例中房室折返性心动过速（ＡＶＲＴ）７９例，慢－快型房室结折返性心动过速（ＡＶＮＲＴ）２１例。首次消融成功９６例（９６％）。失败４例均为ＡＶＲＴ。平均Ｘ线曝光时间１９ｍｉｎ。除２例ＡＶＮＲＴ放置导管过程中发生一过性ＩＩ度房室阻滞（ＡＶＢ）外，余术中和术后均无并发症发生。术后随访１个月～４．５年，ＡＶＲＴ复发１例，ＡＶＮＲＴ复发４例（占２１例的１９％），总复发率５％。结论：①ＲＦＣＡ治疗儿童ＰＳＶＴ安全、有效。②因儿童的ＡＶＮＲＴ消融慢径易出现ＡＶＢ且复发率高，应严格掌握手术适应证。③术中Ｘ线曝光时间应＜４０ｍｉｎ。     

心房起搏法在射频消融房室结折返性心运过速中的应用

将射频消融治疗的９４例房室结折返性心动过速（ＡＶＮＲＴ）病人按心房起搏法和常规法进行分组（分别为３９及５５例），回顾性比较两组病人的消融治疗结果，以评价这两种方法在射频消融治疗ＡＶＮＲＴ中的安全性、成功率和复发率。随访１０．８±４．５个月，总成功率为９６．８％，复发率为２．１％。与常规组相比，起搏组有效放电时间明显延长（１４５±３８ｓｖｓ８２±２６ｓ，Ｐ〈０．０１），慢径阻断成功率高（６１．５％ｓ     

A Quantitative Fluoroscopic Comparison of the Coronary Sinus Ostium in Patients With and Without AV Nodal Reentrant Tachycardia

Coronary Sinus Ostium. Introduction : The purpose of this study was to perform a quantitative fluoroscopic analysis of the coronary sinus ostium and its relationship to the His bundle in patients with and without AV nodal reentrant tachycardia. Sites of slow pathway ablation are often near the coronary sinus ostium, which can be located within a few millimeters of the His bundle. Whether such close proximity of the coronary sinus ostium to the His bundle is unique to patients with AV nodal reentrant tachycardia is unknown.
Methods and Results : Fifty consecutive patients (mean age 39 ± 14 years) with no structural heart disease underwent electrophysiologic testing and radiofrequency ablation. The study group consisted of 28 patients with inducible AV nodal reentrant tachycardia or dual AV nodal physiology and 22 patients in the control group. A coronary sinus venogram was performed in each patient. The coronary sinus ostium was similar in size in the study group (11.4 ± 4.5 mm) and in the control group (10.5 ± 3.6 mm, P = 0.2). The coronary sinus ostium was funnel shaped in half of the study patients and in half of the control patients (P = 1.0). The mean distance from the upper lip of the coronary sinus ostium to the tip of the His bundle catheter was 9.7 ± 5.5 mm in the study group and 10.4 ± 5.1 mm in the control group (P = 0.7). The mean distance from the lower lip of the coronary sinus ostium to the tip of the His-bundle catheter in the study group was 20.1 ± 6.1 mm and 19.5 ± 5.6 mm in the control group (P =0.7).
Conclusion : This study demonstrates a wide range of normal coronary sinus ostium diameters, morphology, and anatomic relationships with surrounding structures, with no demonstrable correlation to the presence or absence of dual AV node physiology or AV nodal reentrant tachycardia.     

His束记录部位非常靠近冠状窦口的房室结折返性心动过速的消融治疗

探讨His束记录部位非常靠近冠状窦口时的房室结折返性心动过速 (AVNRT)的射频消融方法及有效性。对7例His束记录部位非常靠近冠状窦口的AVNRT的患者进行射频消融 ,男 5例、女 2例 ,年龄 6 5 .3± 3.5 (6 0～ 75 )岁。常规放置电极导管至高位右房、His束和冠状窦 ,发现 4例记录到最大His束电位的部位与冠状窦口位于同一水平线 ,3例在其下方 2～ 4mm。采用左前斜位 (LAO) 4 5°和右前斜位 30°,尤其是LAO 4 5°在最大His束电位记录部位下方 ,细标靶点 ,当A波碎裂 ,或记录到慢径电位 ,而无His束电位时试放电消融。 6例成功 ,其中 4例在LAO相当于 6点处消融成功 ,2例在 6点半左右处成功 ,1例应用了Swartz鞘。平均手术时间 1.5± 0 .3h。随访 1～ 2年 ,6例成功患者未见复发。结论 :对His束最大记录部位非常靠近冠状窦口的患者 ,主要在LAO 4 5°冠状窦口下方细标靶点 ,可提高慢径消融的成功率并节省时间     

Prospective evaluation of the coronary sinus anatomy in patients undergoing electrophysiologic study.

BACKGROUND: Previous retrospective studies could find a predominant incidence of coronary sinus (CS) anomalies in patients with accessory pathways and a characteristic anatomy of the CS ostium in patients with atrioventricular nodal reentrant tachycardias (AVNRT). HYPOTHESIS: In the present prospective study, CS angiograms were prospectively performed to analyze the incidence of CS anomalies and to measure the diameters of the CS ostium. METHODS: The study included patients referred for electrophysiologic study and catheter ablation of various tachyarrhythmias. The anatomy of the CS and its side branches was visualized [left anterior oblique (LAO) 30 degrees, right anterior oblique (RAO) 30 degrees] by retrograde angiography in 204 consecutive patients (82 women, 122 men, age 45 +/- 15 years); of these, 120 presented with 123 accessory pathways (45 left-sided, 33 right-sided, 45 septal). The diagnosis in the remaining patients was atrioventricular nodal reentrant tachycardia in 43 cases, atrial tachycardia or atrial fibrillation in 12, and ventricular tachycardia in 15. In 14 patients, the indication for the electrophysiologic study was an unexplained syncope. The CS angiogram was evaluated for anomalies and the size of the CS ostium was manually measured in both projections. RESULTS: Anomalies of the CS defined as diverticula, persistent left superior vena cava, or enlarged CS ostia were found in 18 patients (9%). Of those, CS diverticula were found in nine patients, all with a posteroseptal or left posterior manifest accessory pathway, which was abolished within the neck of the diverticulum in seven patients and at the posteroseptal tricuspid annulus in two patients. Persistence of the left superior vena cava was found in five patients, four had atrioventricular reentrant tachycardia secondary to five accessory pathways (left free wall in four, right midseptal in one), and one patient had atrioventricular nodal reentrant tachycardia (AVNRT). Enlargement of the CS ostium of > 25 mm width was detected in nine patients (5%), of whom four had AVNRT. However, the width of the CS ostium generally did not differ significantly between patients with AVNRT (LAO: 14.4 +/- 5.6; RAO 9.3 +/- 2.4 mm) compared with the control group (LAO 13.4 +/- 4.1; 8.2 +/- 1.9 mm). CONCLUSIONS: Anomalies of the CS as diverticula, persistent superior vena cava, or enlargement of the CS ostium are predominantly found in patients with accessory pathway-related tachycardias. Diverticula of the proximal CS were found in 7% of patients with accessory pathways; in these cases, ablation succeeded mostly by radiofrequency (RF) current delivery in the neck of the diverticulum. Enlargement of the CS ostium was more often seen in patients with AVNRT than in all other patients. However, in general the measurements of the coronary sinus ostium did not significantly differ in patients with AVNRT compared with the control group.     

房室结折返性心动过速合并束支阻滞时心内电图特征

探讨房室结折返性心动过速 (AVNR)合并束支阻滞时心内电图特征及其机制。 6 0例AVNRT患者 ,男 2 3例、女 37例 ,年龄 39± 11岁。将病例分为 3组 :Ⅰ组合并左束支组滞 (CLBBB) ;Ⅱ组合并右束支阻滞 (CRBBB) ;Ⅲ组无束支阻滞。心内电生理测定心动过速的频率 (HR)、冠状窦口A波至V波的距离 (AVcs)、His束处A波到V波的距离 (AVH)。三组心动过速的心率分别为 171± 2 3,16 6± 19,170± 17次 /分 ,三组之间差异无显著性 (P >0 .0 5 ) ;Ⅰ组与Ⅱ、Ⅲ组AVcs、AVH 比较 ,差异有显著性 ( 81± 12msvs 46± 11ms,49± 9ms;5 6± 13msvs 5 1± 10ms、5 0± 10ms,P均 <0 .0 5 ) ;Ⅱ组与Ⅲ组之间AVcs、AVH 差异无显著性。结论 :AVNRT合并束支阻滞时心动过速的心率无明显变化 ;当合并CLBBB时 ,His束到心室的传导时间延长 ,导致冠状窦与His束处的A、V间距延长 ;合并CRBBB时无上述现象发生。     

寻找慢径最早心房出口射频消融治疗快-慢型房室结折返性心动过速

探讨快 慢型房室结折返性心动过速 (AVNRT)射频消融治疗的方法学。 7例快 慢型AVNRT患者 ,在心动过速发作时 ,寻找慢径最早心房出口作为靶点行射频消融治疗。6例消融成功。与冠状静脉窦口 (CSp)相比 ,成功靶点A波提前程度平均为 9.8± 1.3ms。手术时间 87± 2 4min ,X线曝光时间 2 7± 12min ,无并发症 ,随访无 1例复发。结论 :激动标测寻找最早心房出口点作为消融靶点 ,是射频消融治疗快 慢型AVNRT安全有效的方法     

Left atrionodal connections in typical and atypical atrioventricular nodal reentrant tachycardias: activation sequence in the coronary sinus and results of radiofrequency catheter ablation

INTRODUCTION: The presence of atrionodal connections and coronary sinus (CS) breakthrough in atrioventricular nodal reentrant tachycardia (AVNRT) has been suggested. However, the incidence, anatomic relationship with reentrant circuit, and results of catheter ablation are unknown. METHODS AND RESULTS: Fifty-two patients with typical slow/fast AVNRT and 10 patients with atypical slow/intermediate or fast/slow AVNRT were included. Eccentric activation of the CS (EACS) was observed in 3 of 52 patients with typical and 8 of 10 patients with atypical AVNRT. The earliest CS activation in patients with an EACS was recorded at a site 10-20 mm inside the CS ostium. The postpacing interval after transient entrainment at the proximal CS in patients with EACS was 23 +/- 21 msec longer than the pacing cycle length. Modification or ablation of the slow pathway was successful in all patients with typical slow/fast AVNRT and in 7 of 9 patients with atypical AVNRT by RF energy delivered at the right septal tricuspid annulus (TA). In 2 patients with atypical AVNRT and an EACS, RF delivery inside the CS targeting the earliest CS activation eliminated the sustained AVNRT. CONCLUSION: Eccentric coronary sinus activation is observed in some rare cases of typical AVNRT, and in a majority of atypical AVNRT. Entrainment results suggest that the proximal coronary sinus may be part of the reentrant circuit. RF ablation of atypical AVNRT, if it fails from the standard right-side approach, can be targeted at the site of earliest retrograde atrial activation inside the CS.     

Anterograde slow pathway is not the same as retrograde slow pathway conducted in the reverse direction in patients with uncommon atrioventricular nodal reentrant tachycardia

INTRODUCTION: The aim of this study was to examine the location of anterograde and retrograde slow pathways in 16 patients with uncommon atrioventricular nodal reentrant tachycardia (AVNRT), including the fast-slow form in 10, slow-slow form in 5, and both fast-slow and slow-slow forms in 1. METHODS AND RESULTS: Patients were divided into two groups according to the approach used for slow pathway ablation in the initial radiofrequency catheter ablation (RFCA): one approach used earliest atrial activation during tachycardia (ES group, n = 9), and the other used a slow potential during sinus rhythm (SP group, n = 7). When the initial RFCA failed to eliminate slow pathway conduction in the ES group, an additional RFCA guided by a slow potential was performed. The ratio of lengths from the His-bundle region to the RFCA site and coronary sinus ostium (Abl/His-CS ratio) and the ratio of amplitudes of atrial and ventricular potentials at the RFCA site (A/V ratio) were compared between the two groups. In the initial RFCA, retrograde slow pathway conduction was eliminated without impairment of anterograde slow pathway conduction in 8 (89%) patients from the ES group, and bidirectional slow pathway conduction was eliminated in 6 (86%) patients from the SP group. Residual anterograde slow pathway conduction that was preserved after the initial RFCA in 8 of 9 patients was eliminated by an additional slow potential-guided RFCA. Both the Abl/His-CS ratio (0.86 +/- 0.07 vs 0.73 +/- 0.11, P = 0.01) and A/V ratio (0.80 +/- 0.31 vs. 0.14 +/- 0.01, P < 0.001) were higher in the ES group than the SP group. The ratios for the residual anterograde slow pathway ablation in the ES group were similar to those in the SP group. CONCLUSION: The results of this study suggest that the retrograde slow pathway runs more on the atrial side of the tricuspid valve annulus at the level of the coronary sinus ostium compared with the anterograde slow pathway, although both pathways run parallel or are fused in portions more proximal to the His bundle.     

Presence and significance of the left atrionodal connection during atrioventricular nodal reentrant tachycardia.

It has been suggested that the anatomic substrates of dual atrioventricular nodal pathways are likely to be the atrionodal connections. During atrioventricular nodal re-entrant tachycardia (AVNRT) or ventricular pacing (VP), an earliest retrograde atrial activation in the coronary sinus (CS) distal to the ostium (CS breakthrough) would suggest the presence of an exit from a left atrionodal connection. The aim of the study was to evaluate the incidence of such an atrial retrograde activation in the CS during AVNRT and VP. The retrograde atrial activation was recorded during typical AVNRT (38 patients, 27 women, mean age 44 +/- 18 years) by a multipolar catheter in the CS, a decapolar catheter in the His bundle position, and a deflectable quadripolar catheter along the tricuspid annulus anterior to the CS ostium. In 31 patients the retrograde atrial activation was recorded also during VP at a similar cycle length. A CS breakthrough was found in 18 patients during AVNRT (47%) and in 13 patients during VP (42%). Presence or absence of CS breakthrough was concordant between AVNRT and VP in 90% of the patients. A CS breakthrough, suggesting a left-sided atrionodal connection, is frequently recorded both during AVNRT and VP. In patients with a CS breakthrough pattern, the absence of correlation between the His bundle to the earliest CS retrograde atrial electrogram interval and AVNRT cycle length, or any other atrial activation times recorded in the posterior and anterior region of the Koch's triangle, would suggest that the left-sided atrionodal connection is a bystander during typical AVNRT.     

Coronary sinus morphology in different types of supraventricular tachycardias

Background: Atrioventricular nodal reentry tachycardia (AVNRT) is based on the concept of dual AV node pathways that are functionally and anatomically distinct. The bigger coronary sinus ostium (CSO) in patients with AVNRT compared to other supraventricular tachycardias (SVTs) may produce separation of atrial inputs into the AV node or create anisotropic conduction, thus giving rise to a different AV nodal physiology. Previous studies measuring the size of the CSO using CS angiography between patients with AVNRT and other SVTs showed conflicting results. Besides, no previous studies have compared the CS morphology of the different forms of AVNRT. Objectives: This study compares the size and morphology of the CS among patients with typical AVNRT, atypical AVNRT and accessory pathways mediated reentrant tachycardia (AVRT). Methods: Ninety-six patients with clinically documented SVTs were divided into three groups. The diameter of the CS was measured in LAO projection during end ventricular systole (by choosing the last ventricular inward motion). The CSO as well as 5, 10 and 15 mm inside the CS were measured. CS morphology is defined as either wind-sock shape or tubular shape. Results: The size of the CS ostium was 13.58 ± 3.98, 15.93 ± 4.86 and 12.50 ± 2.83 mm for the atypical AVNRT, typical AVNRT and AVRT, respectively (p = 0.03). There was significant difference in the size of the CS from the ostium until 15 mm into the CS between 1) typical AVNRT and AVRT, 2) typical AVNRT and atypical AVNRT. Typical and atypical AVNRT patients had more windsock morphology CS (13/32, 40.6% and 10/32, 31.2%) compared to AVRT which had only one (1/32, 3.1%) windsock morphology (p = 0.002). Conclusion: The easier CS cannulation in patients with typical AVNRT could be due to a bigger CS size and to a more windsock morphology. The CS size and morphology may be a very important substrate of tachycardia in patients with AVNRT.     

A simple technique for anatomical slow pathway ablation in atrioventricular nodal reentrant tachycardia

The slow pathway potential or the slow potential serves as a useful marker in catheter ablation of the slow pathway. However, an anatomical approach without recording of these potentials is also an effective way to cure atrioventricular nodal reentrant tachycardia (AVNRT). Moreover, the origin of these potentials is a matter of controversy. We compared 2 approaches to ascertain whether or not recording of these potentials is necessary in eliminating the slow pathway and to estimate the usefulness of the simple anatomical approach. The study population consisted of 24 patients with a conventional approach (Group P) and 19 patients with an anatomical approach (Group A). In group A, the ablation site was determined by fluoroscopy, which was the lowest one-third of the area between the His bundle electrogram recorded position and the coronary sinus orifice at the right anterior oblique view, and just in front of and above the coronary sinus orifice also posterior to the His catheter at the left anterior oblique view where the His catheter was seen tangentially. The slow pathway was successfully ablated in all patients without any complications, including more than first-degree AV block. Although there were no significant differences in total energy or number of applications between the 2 groups, the procedure time was significantly shorter in group A (p < 0.01). In conclusion, recording of the slow pathway potential or the slow potential is not always necessary for slow pathway ablation in the treatment of AVNRT. Because our anatomical approach was performed simply, effectively and safely, it is recommended for the slow pathway ablation of AVNRT.