体表心电图对房室结折返性与房室折返性心动过速的鉴别诊断

为探讨体表心电图对房室结折返性和房室折返性心动过速的鉴别诊断价值,对以射频导管消融、心脏电生理检查、心外膜标测的方法确诊房室结折返性心动过速(AVNRT)和房室折返性心动过速(AVRT)的88例患者的室上性心动过速发作时心电图作对照研究。结果显示:(1)P'波出现率在AVNRT占33％,在AVRT占100％(P<0.01)。(2)R-P'间期<80ms时常见于AVNRT,而≥80ms多见于AVRT(P<0.01)。(3)AVNRT在下壁导联(Ⅱ、Ⅲ、aVF)常见假性S波,而V_1导联常合并假性r波。(4)AVRT无文氏现象,但常出现束支传导阻滞改变且符合Coumel-Slama定律。认为以上特点对两者鉴别诊断有重要价值。     

体表心电图特征对典型的房室结折返性心动过速和房室折返性心动过速的鉴别作用

对150例射频消融明确诊断的窄QRS心动过速患者的窦性心律和发作室上性心动过速时的心电图进行分析,从而归纳出典型的房室结折返性心动过速(AVNRT)和房室折返性心动过速(AVRT)心电图特征的差异.结果 5项心电图指标对区分这两种心动过速类型有意义.认为对于AVNRT有预测作用的为伪r′波(V1导联)和伪S波(Ⅱ、Ⅲ、aVF导联).对于AVRT有预测作用的为逆传P波,RP′间期≥70 ms及ST段改变.     

aVL导联切迹对慢快型房室结折返性心动过速的诊断价值

目的探讨aVL导联切迹在慢快型房室结折返性心动过速(AVNRT)和顺传型房室折返性心动过速(AVRT)鉴别诊断中的作用。方法对138例经心内电生理检查及射频导管消融术治疗成功的阵发性窄QRS波心动过速患者12导联心电图进行分析,其中AVNRT 74例,AVRT 64例,比较传统指标与单独aVL导联切迹对AVNRT与AVRT鉴别价值。结果 aVL导联切迹在AVNRT出现29例(39.2%),在AVRT出现1例(P<0.01);下壁导联伪s波在AVNRT出现28例(37.8%),在AVRT出现1例(1.6%,P<0.01);V1导联伪r’波在AVNRT出现33例(44.6%),在AVRT出现3例(4.7%,P<0.01)。aVL导联切迹诊断AVNRT的敏感性为39.2%、特异性为98.4%;下壁导联伪s波诊断AVNRT的敏感性为37.8%、特异性为98.4%;V1导联伪r’波诊断AVNRT的敏感性为44.6%、特异性为95.3%,三种判断标准的敏感性、特异性差异无统计学意义(P>0.05)。结论以aVL导联切迹为判断标准,对慢快型AVNRT的诊断特异性强,敏感性较高,可作为房室结折返性心动过速的诊断指标之一。     

慢快型房室结折返性心动过速的诱发及终止方式

慢快型房室结折返性心动过速（AVNRT）是阵发性室上性心动过速的另一常见类型，有时在体表心电图不易与顺向性房室折返性心动过速（AVRT）鉴别。了解慢快型AVNRT的诱发和终止方式及其电生理特征，在与AVRT的诊断及鉴别诊断方面有着重要的临床意义。     

心电图aVL导联对阵发性室上性心动过速折返途径的鉴别作用

目的:研究体表心电图aVL导联对阵发性室上性心动过速的鉴别诊断作用。方法:选取2009-01至2009-11因症状性阵发性室上性心动过速在我院行心脏射频消融术(RFCA)治疗的连续病例112例,按心动过速类型分为房室结折返性心动过速(AVNRT,n=60)和房室折返性心动过速(AVRT,n=52),比较两者心电图特点。结果:AVNRT与AVRT患者在年龄上差异没有统计学意义(P0.05),但是AVNRT中女性患者的比例多于AVRT(55.6%和33.3%,P=0.04)。aVL切迹与V1导联伪R波及下壁导联伪S波(标准心电图算法)发生在AVNRT的比例均大于AVRT(P均0.001)。aVR导联ST段抬高发生在AVNRT的比例小于AVRT(P=0.0001),并且在AVRT患者中71.4%为左侧旁道。QRS电交替在AVRT和AVNRT间差异没有统计学意义(P0.05)。aVL切迹和V1导联伪R波及下壁导联伪S波诊断AVNRT的敏感性分别为53.3%、46.7%,42.2%,特异性分别是82.1%、84.6%、94.9%。aVL切迹诊断AVNRT的敏感性高于V1导联伪R波及下壁导联伪S波(标准心电图算法),但是三者之间差异没有统计学意义(P0.05)。结论:aVL切迹多发生于AVNRT并有助于AVNRT和AVRT的鉴别诊断。     

快慢型房室结折返性心动过速的电生理特点

目的观察快慢型房室结折返性心动过速的体表心电图和心内电生理特点.方法分析29例快慢型房室结折返性心动过速(FS,简称FS组)的体表心电图和心内电生理参数,并与61例慢快型房室结折返性心动过速(SF,简称SF组)的心内电生理进行比较.结果FS组心电图RP＞PR,PR间期平均为122±37 ms,其中5例PR≤100 ms,P波在QRS波群之前,类似交界区心动过速,P波在Ⅱ、Ⅲ、aVF导联为完全负向,V1导联为负正双向.FS组无AH间期跳跃现象较SF组更常见(69.0%vs.19.7%,有显著性差异P＜0.05);FS组心房和心室刺激更易诱发心动过速(79.3%vs.6.6%,有显著性差异P＜0.05).结论FS具有独特的体表心电图和心内电生理特点,这些特点有助于其诊断和射频导管消融治疗.     

窄QRS波群心动过速时ST-T改变的价值探讨

目的探讨窄QRS波群心动过速（NQRST）时ST-T改变对鉴别房室结折返性心动过速（AVNRT）与房室折返性心动过速（AVRT）的价值以及旁道位置的定位。方法观察100例NQRST者心电图ST段压低的部位、程度以及T波倒置等情况。结果AVRT的ST段压低〉2mm且持续≥100ms,ST段压低幅度均显著大于AVNRT,左侧游离壁旁道ST段压低的导联多见于V1～6导联。结论ST-T改变有助于AVNRT和AVRT的鉴别和旁道位置的初步定位。     

顺向型房室折返性心动过速与慢快型房室结折返性心动过速的分析与鉴别（1）

阵发性室上性心动过速以顺向型房室折返性心动过速（AVRT）和慢快型房室结折返性心动过速（AVNRT）最常见,通常阵发性室上性心动过速即指这两种类型的心动过速。由于两者在QRS形态和频率方面相似,R—P-间期均〈P-R间期,有时鉴别较为困难。但详细分析各自的电生理特征和心电图改变仍可明确诊断,通过对顺向型AVRT的P波形态分析,甚至可对房室旁道作出初步定位诊断。     

常规心电图对典型的房室结折返性心动过速和顺传型房室折返性心动过速的鉴别作用

目的探讨12导联心电图对阵发性窄QRS心动过速中最常见两种类型--典型的房室结折返性心动过速（AVNRT）和顺传型房室折返性心动过速（AVRT）的鉴别作用.方法对206例阵发性窄QRS心动过速（QRS〈0.11 s,心室率〉120次/min）患者的心电图进行了分析.第一部分分析139例患者的心电图,从中归纳出1个12导联心电图算法（algorithm）.第二部分前瞻性分析了67例患者的心电图,以检测这一算法的准确性.心动过速的机制和旁路位置均由成功的射频导管消融术确定.结果 5项心电图指标对区分这两种心动过速类型有意义.对于AVNRT有预测作用的为伪r′波（V1导联,敏感性53%、特异性96%）,伪S波（Ⅱ、Ⅲ、aVF导联,敏感性21%、特异性100%）.对于AVRT有预测作用的为逆传P波（敏感性89%、特异性68%）,RP间期〉70 ms（敏感性90%、特异性91%）,及ST段改变.ST段改变归纳出3个联合指标,分别为：V4、V5导联ST段同时下降≥2 mm（敏感性24%、特异性94%）;V5、V6导联ST段同时下降≥1 mm（敏感性41%、特异性81%）;V6导联ST段同时下降≥1 mm和aVR导联ST段抬高≥1 mm同时出现（敏感性30%、特异性85%）.V1导联逆传P波极性对于旁路的初步定位有帮助,左侧旁路大多为直立、双向或平坦的逆传P波,右侧旁路大多为倒置的逆传P波.12导联心电图算法对心动过速机制的正确诊断率分别为85%和82%.对于AVRT旁路位置的正确判断率为75%～86%.在3个联合指标中,V5、V6导联ST段同时下降≥1 mm的鉴别作用最佳.结论心电图算法有助于更加准确地鉴别阵发性窄QRS心动过速的机制,并且可以对旁路初步定位.     

体表心电图对AVRT及AVNRT的诊断价值和方法

通过对６６例房室折返性心动过速及房室结折返性心动过速及体表心电图与心内电生理检查结果对比分析,总心动过速时体表心电图逆传Ｐ波使波形改变的规律,从而利于用体表心电图对ＡＶＮＲＴ及ＡＶＲＴ鉴别诊断。     

食管心房调搏指标诊断室上性心动过速价值的评定

以射频消融结果为依据，评定Ｓ＿２Ｒ跃增值和ＲＰ＿Ｅ时距对４８例慢－快型房室结折返性心动过速（Ｓ－Ｆ型ＡＶＮＲＴ）和１４１例顺向型房室折返性心动过速（Ｏ－ＡＶＲＴ）患者的诊断及鉴别诊断价值，并讨论两类心动过速食管调搏的定量判别标准。结果表明：（１）Ｓ＿２Ｒ跃增以≥６０ｍｓ诊断ＡＶＮＲＴ为宜，但有一定局限性，其敏感性、特异性、诊断价值分别为９１．６％、８５．８％、７２．８％。（２）ＲＰ＿Ｅ时距≤７０ｍｓ和＞７０ｍｓ分别对Ｓ－Ｆ型ＡＶＮＲＴ、Ｏ－ＡＶＲＴ的诊断及鉴别诊断价值较高。敏感性、特异性、诊断价值分别为９３．８％、１００％、１００％与１００％、９３．８％、９７．９％．（３）少数（１７％）右侧壁旁道逆传性心动过速ＲＰ＿Ｅ／Ｐ＿ＥＲ可＞１．０。（４）Ｓ－Ｆ型ＡＶＮＲＴ与Ｏ－ＡＶＲＴ的定量判别Ｓ＿２Ｒ跃增、ＲＰ＿Ｅ标准宜分别取≥６０ｍｓ、≤７０ｍｓ与＜６０ｍｓ、＞７０ｍｓ。     

心房不同部位拖带法鉴别不典型房室结折返性心动过速和房性心动过速

目的报道一种鉴别不典型房室结折返性心动过速(AVNRT)和起源点邻近Kock三角的房性心动过速(AT)的新方法。方法 22例室上性心动过速患者,在心房不同部位(右房心耳部、冠状静脉窦近端、远端)起搏拖带心动过速,测定起搏后VA间期(最后一个起搏脉冲前传夺获的心室电图到起搏终止后第一心搏的最早心房电图的距离)。计算各部位起搏后VA间期的差别并取差别绝对数的最大值定义为ΔVA间期。结果 13例AVNRT起搏后ΔVA间期5.8±3.6(0～14)ms,9例AT起搏后ΔVA间期62.8±24.2(21～98)ms。ΔVA间期在所有AVNRT均<15 ms,在所有AT均>15 ms,因此起搏后ΔVA间期>15 ms用于诊断AT的灵敏度和特异度均为100%。结论心房不同部位起搏拖带法可用于准确鉴别不典型AVNRT和起源点邻近Kock三角的AT。     

心室融合波伴心房激动提前对间隔旁路逆传的房室折返性心动过速的诊断作用

目的 观察心室融合波伴心房激动提前对间隔旁路逆传的顺向型房室折返性心动过速(OAVRT)的诊断作用。方法 按心内电生理检查标准和射频消融结果，将47例符合人选条件的患者分为两组：房室结折返性心动过速(AVNRT)组和间隔旁路逆传的0AVRT组，分别为24例和23例。心动过速时行心室期前程序刺激(RS2刺激)和心室快速刺激，测量体表心电图上心室融合波之后的心房激动时间是否提前。结果 RS2刺激和心室快速刺激均能形成多个心室融合波。AVNRT组无l例伴有心房激动提前(特异性100％)，而OAVRT组在心室刺激成分明显的心室融合波时，心房激动均被提前(敏感性100％)。两组间的差异十分显著(P＜0．001)。结论 心室融合波伴心房激动时间提前是诊断间隔旁路逆传OAVRT的可靠指标，具有敏感性和特异性高的特点，而且也可用于未能记录到希氏束电图的患者。     

食管心房调搏诊断室上性心动过速的临床研究

为探讨食管心房调搏揭示室上性心动过速发生机制的价值和局限性,回顾性分析成功射频导管消融的１３８例隐匿性单房室旁道参与的顺向型房室折返性心动过速和１００例单一类型房室结折返性心动过速的食管心房调搏结果。结果显示：前１３８例中,３例前间隔旁道引起者食管心房调搏均诊断为房室结折返性心动过速余为左右侧其它部位的旁道,诊断正确。后１００例中,５例为慢－慢型,２例为快－慢型,食管心房调搏均诊断为房室折返性心动     

隐匿性拖带时起搏后间期与慢径消融成功靶点的关系

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 )在成功靶点与不成功靶点区别。结果 :HRA超速起搏发生隐匿性拖带时 ,His束记录部位A波均为逆向夺获。而CSO超速起搏拖带时 ,32例His束记录部位A波为顺向夺获 ,另 2例为逆向夺获。在这 32例中共记录 5 4个靶点 ,成功靶点的PPI-TCL值明显小于不成功靶点 (12 .4± 5 .8msvs 32 .1± 18.6ms,P <0 .0 1)。PPI-TCL值≤ 2 0ms对靶点成功消融的敏感性和特异性分别为 84%、81%。结论 :本研究提示常规慢径消融成功部位作为房室结外的后部延伸组织参与组成AVNRT折返环或距其非常近。在可持续发作和诱发的AVNRT患者中 ,CSO部位起搏拖带顺向心房夺获时 ,靶点部位测出的PPI-TCL值≤ 2 0ms,可作为一种新的慢径路电生理定位消融方法     

The VA relationship after differential atrial overdrive pacing: a novel tool for the diagnosis of atrial tachycardia in the electrophysiologic laboratory

Introduction: Despite recent advances in clinical electrophysiology, diagnosis of atrial tachycardia (AT) originating near Koch's triangle remains challenging. We sought a novel technique for rapid and accurate diagnosis of AT in the electrophysiologic laboratory.
Methods: Sixty-two supraventricular tachycardias including 18 ATs (10 ATs arising from near Koch's triangle), 32 atrioventricular nodal reentrant tachycardias (AVNRTs), and 12 orthodromic reciprocating tachycardias (ORTs) were studied. Overdrive pacing during the tachycardia from different atrial sites was performed, and the maximal difference in the postpacing VA intervals (last captured ventricular electrogram to the earliest atrial electrogram of the initial beat after pacing) among the different pacing sites was calculated (delta-VA interval).
Results: The delta-VA intervals were >14 ms in all AT patients and <14 ms in all AVNRT/ORT patients, and thus, the delta-VA interval was diagnostic for AT with the sensitivity, specificity, and positive and negative predictive values all being 100%. When the diagnostic value of the delta-VA interval and conventional maneuvers were compared for differentiating AT from atypical AVNRT, both a delta-VA interval >14 ms and "atrial-atrial-ventricular" response after overdrive ventricular pacing during the tachycardia were diagnostic. However, the "atrial-atrial-ventricular" response criterion was available in only 52% of the patients because of poor ventriculoatrial conduction.
Conclusions: The delta-VA interval was useful for diagnosing AT irrespective of patient conditions such as ventriculoatrial conduction.     

心室起搏拖带对房室结折返性和间隔旁路参与的房室折返性心动过速的鉴别作用

目的　研究心动过速时心室起搏拖带对房室结折返性心动过速 (AVNRT )和间隔旁路参与的顺向型房室折返性心动过速 (间隔旁路ORT)的鉴别意义。方法　 30例AVNRT和 2 5例间隔旁路ORT病人在心动过速发生后 ,采用较心动过速的周长 (TCL)短 10～ 4 0ms的周长行右心室起搏拖带心动过速。测量右心室起搏之前的心室 心房 (VA)间期和TCL。停止起搏后 ,测量最后一次刺激信号至最后起搏拖带的心房激动 (SA)间期 ,以及起搏后间期 (PPI)。结果　所有 30例AVNRT病人的SA -VA间期 >85ms、PPI-TCL >115ms,而 2 5例ORT病人的SA -VA间期 <85ms、PPI-TCL <115ms。结论　PPI TCL和SA VA间期是鉴别AVNRT和间隔旁路ORT的非常可靠的指标 ,具有较高的特异性。     

Differentiating atrioventricular nodal reentrant tachycardia from junctional tachycardia: novel application of the delta H-A interval

Introduction: Junctional tachycardia (JT) and atrioventricular nodal reentrant tachycardia (AVNRT) can be difficult to differentiate. Yet, the two arrhythmias require distinct diagnostic and therapeutic approaches. We explored the utility of the delta H-A interval as a novel technique to differentiate these two tachycardias.
Methods: We included 35 patients undergoing electrophysiology study who had typical AVNRT, 31 of whom also had JT during slow pathway ablation, and four of whom had spontaneous JT during isoproterenol administration. We measured the H-A interval during tachycardia (H-A_T) and during ventricular pacing (H-A_P) from the basal right ventricle. Interobserver and intraobserver reliability of measurements was assessed. Ventricular pacing was performed at approximately the same rate as tachycardia. The delta H-A interval was calculated as the H-A_P minus the H-A_T.
Results: There was excellent interobserver and intraobserver agreement for measurement of the H-A interval. The average delta H-A interval was −10 ms during AVNRT and 9 ms during JT (P < 0.00001). For the diagnosis of JT, a delta H-A interval ≥ 0 ms had the sensitivity of 89%, specificity of 83%, positive predictive value of 84%, and negative predictive value of 88%. The delta H-A interval was longer in men than in women with JT, but no gender-based differences were seen with AVNRT. There was no difference in the H-A interval based on age ≤ 60 years.
Conclusion: The delta H-A interval is a novel and reproducibly measurable interval that aids the differentiation of JT and AVNRT during electrophysiology studies.     

Risk of development of delayed atrioventricular block after slow pathway modification in patients with atrioventricular nodal reentrant tachycardia and a pre-existing prolonged PR interval.

AIMS: The objective of this prospective study was to assess risk factors for the development of atrioventricular block following slow pathway modification in patients with atrioventricular nodal reentrant tachycardia and a pre-existing prolonged PR interval. METHODS AND RESULTS: Of 346 consecutive patients with atrioventricular nodal reentrant tachycardia undergoing slow pathway modification, 18 patients (62 +/- 7 years; five females) were found to have a prolonged PR interval prior to ablation. Total elimination of the functional slow pathway was assumed if the antegrade effective refractory period following slow pathway modification was longer than the cycle length of atrioventricular nodal reentrant tachycardia. To detect atrioventricular node conduction disturbances, 24-h Holter recordings were performed 1 day prior to slow pathway modification, and 1 day, 1 week, 1, 3 and 6 months after the procedure. Six patients developed late atrioventricular block. The incidence of delayed atrioventricular block following successful slow pathway modification was higher in patients with, compared to patients without, prolonged PR interval at baseline (6/18 vs 0/328, P < .001). In the former group, the antegrade effective refractory period was longer in patients with, compared to those without, a delayed atrioventricular block (492 +/- 150 ms vs 332 +/- 101 ms, P < 0.05). The incidence of delayed atrioventricular block was higher in patients with total elimination of the slow pathway compared to patients without (5/7 vs 1/11, P < 0.01). CONCLUSIONS: Slow pathway modification in patients with atrioventricular nodal reentrant tachycardia and a prolonged PR interval is highly effective. However, there is a significant risk of development of delayed atrioventricular block, particularly when the procedure results in total elimination of the slow pathway.     

Fast pathway ablation in patients with common atrioventricular nodal reentrant tachycardia and prolonged PR interval during sinus rhythm

Aims This study aimed to clarify the safety and efficacy of selectivefast pathway ablation in patients with atrio-ventricular nodalreentrant tachycardia and a prolonged PR interval during sinusrhythm. Such patients have been reported to have an increasedincidence of complete atrioventricular block. Methods and Results In this study, the earliest retrograde atrial activation duringatrioventricular nodal reentrant tachycardia and right ventricularstimulation was localized. Fast pathway ablation was then performedin five patients with the common form of atrioventricular nodalreentrant tachycardia and a prolonged PR interval. Three ofthe five patients had almost incessant atrioventricular nodalre-entrant tachycardia. Radiofrequency catheter ablation induceda complete ventriculo-atrial block during right ventricularstimulation in four patients and a marked prolongation of ventriculo-atrialconduction during right ventricular stimulation in one. Non-inducibilityof common atrioventricular nodal reentrant tachycardia withand without isoproterenol was achieved in all five patients.The PR interval increased from 254±53ms to 276±48msand the atrio-His interval from 172±46ms to 192±45ms.Second- or third-degree atrioventricular block did not occurduring the ablation procedure. During the follow-up of 19±20months none of the patients developed symptoms suggestive ofatrioventricular nodal reentrant tachycardia or evidence ofsecond- or third-degree atrioventricular block. Conclusion These data suggest that atrioventricular node (retrograde) fastpathway ablation can apparently be safely performed in patientswith common atrioventricular nodal reentrant tachycardia anda prolonged PR interval during sinus rhythm.