非接触球囊标测系统指导下右室流出道室性期前收缩导管消融疗效及体表心电图应用价值

目的:探讨非接触球囊标测系统指导下右室流出道室性期前收缩（室早）导管消融疗效及体表心电图应用价值。方法:术前根据同步12导联体表心电图室早的形态特征初步判断室早起源部位,对58例药物治疗无效的顽固性室早患者进行导管射频消融治疗,其中26例采用传统标测法,32例采用非接触球囊标测法（Ensite三维标测法）。结果:①非接触球囊标测法与传统标测法相比较,成功率高（100% vs. 81%）、复发率低（3% vs. 19%）,X线曝光时间短［(3.6±1.4)min vs.(32±12)min］;②标测和消融结果显示30例患者室早起源于右室流出道间隔部,其中7例起源于前间隔,9例起源于中间隔,14例起源于后间隔。22例患者室早起源于右室流出道游离壁,其中7例起源于前游离壁,4例起源于中游离壁,11例起源于后游离壁。体表心电图特征对判断室早起源部位具有较高的灵敏度、特异度和准确度。结论:非接触球囊标测系统指导右室流出道室性心律失常射频消融安全有效,仔细分析心电图室早QRS波形态特征有助于判定室早起源部位,并缩短手术时间。     

右室流出道起源的特发性室性心律失常的心电图分析

右室流出道是特发性室性心律失常易起源位置,右室流出道起源的室性期前收缩占所有室性期前收缩的80%以上。起源于该处的特发性室性心律失常经射频导管消融治疗的成功率在75%~100%,而且并发症风险低。右室流出道解剖上毗邻左室流出道,尤其是主动脉窦,又是致心律失常性右室心肌病心脏发育不良三角的一部分,其自身又分为前间隔、后间隔和游离壁,术前对此区体表心电图的鉴别诊断尤为重要。     

体表心电图特征鉴别左右室流出道心律失常的临床分析

目的分析体表心电图特点对鉴别流出道室性心律失常(OTVA)起源部位的临床价值。方法对电生理检查及射频消融明确靶点的87例OTVA患者[(其中起源于右室流出道(RVOT)的64例;起源于左室流出道(LVOT)的23例]体表心电图进行分析,分别以R/S振幅指数、R波时限指数、胸导联移行区(TZ)指数、V2转换率及V2S/V3R指数来评估体表心电图特征,分析其对LVOT/RVOT室性心律失常的鉴别的准确性。结果以V1导联R/S波振幅指数≥30%判断OTVA起源于LVOT的灵敏度为60.87%,特异度92.19%,R波时限指数≥50%判断灵敏性为34.78%,特异度96.87%;TZ指数0判断灵敏度为69.57%,特异度87.5%;以V2转换率0.6的判断灵敏度为69.57%,特异度90.63%;V2S/V3R指数≤1.5的判断灵敏度为65.22%,特异度92.19%。结论V2S/V3R指数≤1.5是一种简便准确地鉴别OTVA起源于左右流出道靶点的体表心电图判断方法,具有很好的临床实用价值。     

右室流出道不同部位起搏体表心电图的形态特征研究

右室流出道 (RVOT)是一个相对较大的区域 ,事先定位这一区域内心律失常的起源部位有助于指导射频消融治疗。为评估根据体表 1 2导联心电图定位起源于RVOT不同部位的心律失常 ,选择 90例无器质性心脏病的室上性心动过速患者 (57例房室折返性心动过速、33例房室结折返性心动过速 )进行研究。将RVOT分为游离壁和间隔 ,按距肺动脉瓣的距离由近至远再分上、中、下三部 ,共 6个区。成功进行射频消融后 ,于RVOT不同部位进行起搏 ,并同时记录 1 2导联体表心电图。结果 :在间隔和游离壁起搏时 ,Ⅰ、aVL导联表现为特征性变化。间隔部起搏时Ⅰ导联QRS波形态多变 ,aVL导联QRS波主要呈QS型 ,QRSⅠ/QRSaVL<1 ;在游离壁起搏时 ,Ⅰ导联QRS波主要呈R型 ,aVL导联QRS波形态多变 ,QRSⅠ/QRSaVL>1。Ⅰ、aVL导联QRS波形态特征对判断游离壁和间隔具有较高的特异度和灵敏度。在RVOT上、中、下位起搏时 ,V3导联呈特征性变化 ,分别主要呈R、RS(R/S >1 )、rS(r/S <1 )型。V3导联QRS波形态特征对判断RVOT的上、中、下位具有较高的特异度和灵敏度。结论 :可根据体表心电图图形特征 ,定位RVOT起源的心律失常部位     

流出道室性早搏的体表心电图定位

<正>室性早搏(室早)是临床上最常见的心律失常,可以起源于心室的任何部位,以心室流出道好发,此处的室早导管消融术成功率可达90%~95%。流出道起源的室早体表心电图具有特征性,下壁导联(Ⅱ、Ⅲ、aVF导联)QRS波呈高大直立的R形。根据起源点不同又可以细分为右室流出道起源(前间隔、后间隔和游离壁)及其延伸部位(肺动脉瓣上)、左室     

射频导管消融治疗的特发性室性心律失常心电图特征分析

目的：探讨不同起源的特发性室性期前收缩（PVCs）和（或）室性心动过速（VT）的心电图特征,提出鉴别流程。方法根据射频导管消融PVCs/VT有效靶点或心室最早激动点的X线胸片进行定位,分析不同起源PVCs/VT的12导联心电图QRS波群。结果828例接受导管消融,580例起源于右心室,248例起源于左心室,左、右心室起源者胸导联移行指数＜0的分别占97.58%及7.24%;左和右心室流出道起源者下壁导联多数呈R型,V1上,多数右心室流出道起源者呈rS型,右室间隔起源呈QS型,主动脉瓣上起源者常呈rS或RS型;下壁导联上,左前分支起源者常呈qR型,左后分支起源者常呈rS型。结论结合体表心电图胸导联移行指数、下壁导联和V1上的QRS波群特征可初步判断特发性PVCs/VT的起源部位。     

特发性室性心动过速激动起源部位分区的临床研究

应用体表心电图对特发性节性心动过速（IVT）激动起源点进行分区、定位研究。将心室分为4个区11个部位。Ⅰ区即左室间隔,高、小、低3个那位;Ⅱ区即右主流出道,上、中、下和前后6个部位;Ⅲ区即注定游离壁;Ⅳ区即右室游离壁。20例（除外器质性心脏病）室上性心动过速射频消融成功后,大头导管在分区内起搏并记录12导联起搏心电图,据其特点总结出IVT起源的诊断标准。再根据诊断标准对39例消融成功的IVT病例进行IVT起源判断。结果：右室流出道IVT根据Ⅰ导联QRS波群形态特点分前后,胸前导联R波移行部位分上下。右室游离壁IVT表现为完全性左来支阻滞图形、电轴左偏。左定IVT根据电轴左偏的程度判定IVT起源部位。体表心电图诊断标准除对起源于左室中位间隔IVT诊断的灵敏度（50％）较低外,其余部位诊断的灵敏度、特异度和符合率均较高（75％～100％）。提示体表心电图对IVT起源点的定位有较高的预测价值。     

右心室间隔部希氏束附近室性期前收缩心电图与射频消融

目的 报道右心室流入道间隔部希氏束附近起源室性期前收缩体表心电图特征及射频消融效果。方法 无器质性心脏病频发性室性期前收缩5例,分析其12导联体表心电图室性期前收缩特点;病人接受心内电生理检查,于右心室流入道行激动与起搏标测,以心室激动较体表QRS波提早、消融导管远端起搏图形与体表心电图室性期前收缩相似部位为消融靶点。结果 室性期前收缩QRS波形态：5例病人Ⅰ导联和Ⅱ导联QRS波均呈R型,Ⅲ导联、aVF导联以低振幅波为主,V1导联均呈QS型,胸导联较早转变成qR或R型（发生于V2或V3）,V5、V6均呈高R型;室性期前收缩QRS波时限为110～120ms。5例病人分别于前间隔（2例）、中间隔（1例）、后间隔（2例）标测到消融靶点,放电后前间隔部、后间隔部病人室性期前收缩均消失,中间隔病人消融失败。无房室传导阻滞并发症。随访8～30个月,成功病例未应用抗心律失常药物,无室性期前收缩发作。结论 右心室流入道间隔部希氏束附近起源室性期前收缩体表心电图具有明显的特征,认识这些特征有助于导管标测与射频消融,消融此部位室性期前收缩安全、有效。     

右室流出道不同部位起搏患者体表心电图的特点

目的探讨体表心电图特点与右室流出道不同区域起搏的关系。方法入选186例行右室流出道起搏的患者,根据不同起搏位置,将患者分成间隔上部组(45例)、间隔下部组(24例)、前壁组(101例)及游离壁组(16例)。比较分析4组患者在右心室起搏状态下的体表心电图特点差异。结果 4组患者的临床一般资料比较,差异无统计学意义(P0.05)。4组患者中,游离壁组QRS波时限为(173±14)ms,长于其他3组(P=0.014);QRS波群额面电轴间隔上部组为(61±47)°,而间隔下部组为(-18±52)°(P=0.01);间隔上部组胸前导联移行区指数(transitional zone Index,TZI)最小,而游离壁组最大(P=0.01);在4组患者肢体导联QRS主波方向比较中,间隔上部组下壁(Ⅱ,Ⅲ,a VF)导联QRS主波向上的比例最大。结论体表心电图特点有助于右室流出道起搏电极在不同区域的定位,但受样本量等的影响,仍需大样本的研究加以验证。     

右室流出道室性期前收缩的心电图特征及射频消融治疗

目的:探讨右室流出道室性期前收缩(室性早搏,室早)的心电图特征和评价单导管法消融单形性右室流出道室性早搏的有效性、安全性和实用性。方法:对52例心脏结构正常的右室流出道单形性室早的心电图特征进行分析并行单导管射频消融。采用起搏标测法,以起搏时与自发室性早搏形态波形态完全相同点为消融靶点。结果:右室流出道的室性早搏体表12导联心电图特征,呈完全性左束支阻滞形态,Ⅰ导联呈rs、m、QS及R型,aVR、aVL均呈QS型,Ⅱ、Ⅲ、aVF、V5~6导联均呈单向R波型,胸前导联R波移行区常在V3、V4导联之后。成功消融结果显示26例室早起源右室流出道间隔部:其中前间隔7例、中间隔5例、后间隔14例,游离壁21例:其中前游离壁6例、后游离壁15例,希氏束附近1例,肺动脉瓣下1例。消融即刻成功率94%(49/52),未成功的3例。手术操作时间30~150 min,X线曝光时间5~29 min。术后随访2~48个月无复发。结论:起源于右室流出道的室性早搏有其独特的心电图表现,单导管射频消融可有效、安全地消融心脏结构正常的右室流出道单形性室性早搏。     

体表心电图特征对特发性右心室流出道室性心动过速和室性早搏起源点的定位价值

目的 起源于右心室流出道(RVOT)不同位点的室性心动过速(VT)具有相应的心电图表现,本研究旨在摸索一种相对简单的根据体表心电图进行定位的方法 .方法 将RVOT分为游离壁和间隔而两大区,其中间隔面又分为9个区域.共320例RVOT-VT患者中,对213例既往消融成功患者的靶点与体表12导联心电图中QRS波形态之间的关系进行分析,并在消融前前瞻性地对另外107例患者的消融靶点进行预测,以检验其定位价值.结果 I导联对RVOT起源的VT有特殊的定位价值.在间隔面前部起源时,I导联以负向波为主,多为QS、Qr及rS型,随着起源点从前向后、从上向下,R波逐渐升高,其中起源于间隔侧中带(2、5、8区)时,以"M"型居多,在后壁时则表现为R波且有切迹.游离壁起源者的QRS时限明显延长,I和aVL导联的R波较间隔起源者高,而下壁导联的R波均较间隔的低(P<0.05).在前瞻性分析中,这些参数的敏感度、特异度、阳性和阴性预测值均较高.结论 RV-OT不同部位起源的VT有相应的心电图特征,其中I导联形态尤其具有定位价值,为RVOT心律失常起源提供了简便的定位标准.     

The crochetage pattern in electrocardiograms of pediatric atrial septal defect patients

OBJECTIVES: To test the sensitivity and specificity of the crochetage pattern (a notch near the apex of the R wave in electrocardiographic inferior limb leads) in the pediatric electrocardiogram for detecting patients with a secundum atrial septal defect. PATIENTS AND METHODS: Electrocardiograms from 82 consecutive preoperative pediatric patients with a secundum atrial septal defect confirmed by two-dimensional echocardiography were reviewed for evidence of right ventricular hypertrophy and the crochetage pattern. These electrocardiograms were compared with 244 consecutive preoperative controls consisting of patients with echocardiographically proven patent foramen ovale, ventricular septal defect, pulmonary stenosis, tetralogy of Fallot and patients with normal echocardiogram studies. RESULTS: The electrocardiographic crochetage pattern was observed in 31.7% of preoperative patients with a secundum atrial septal defect in at least one inferior limb lead. The specificity of the crochetage pattern for the detection of a secundum atrial septal defect was high when present in all three inferior limb leads (greater than 92%). The crochetage pattern in at least one lead in secundum atrial septal defects shows no association with incomplete right bundle branch block (c2(1)=0.80, not significant), and thus these two findings together do not improve the detection of an atrial septal defect. CONCLUSIONS: The sensitivity and specificity of the electrocardiographic crochetage patterns in at least one inferior limb lead in echocardiographically proven secundum atrial septal defects are 31.7% and 86.1%, respectively. The electrocardiographic crochetage or notching pattern in inferior limb leads has a high specificity for atrial septal defects in the pediatric population.     

特发性左室流出道室性心律失常的心电图特点

探讨特发性左室流出道室性心律失常患者的心电图特点。对 7例特发性左室流出道室性早搏 (简称室早 )、室性心动过速 (简称室速 )患者进行心电图分析 ,并行心内电生理检查及射频消融治疗 ,同时对 10例预激综合征患者成功消融房室旁道后行主动脉瓣上及瓣下起搏 ,记录同步 12导联起搏心电图。对比分析两组病例体表心电图QRS波图形特点。结果 :7例左室流出道室早、室速患者经心内电生理检查证实 6例起源于冠状动脉窦内 ,1例起源于左室流出道主动脉瓣右瓣下方 ,所有患者经射频消融成功治疗室性心律失常。对照组 10例在主动脉瓣下起搏(其中 6例同时在主动脉瓣上起搏 )获得同步 12导联起搏心电图。两组病例体表心电图共同特点为 :QRS波额面电轴向下 ,Ⅱ、Ⅲ、aVF导联主波向上 ,QRS波在V2 或V3 前移行为Rs或R型。结论 :左室流出道为特发性室早、室速发生部位之一 ,体表心电图有其独特性 ,导管射频消融治疗安全有效。     

Repetitive monomorphic ventricular tachycardia originating from the aortic sinus cusp: electrocardiographic characterization for guiding catheter ablation

OBJECTIVES: We sought to investigate the electrocardiographic (ECG) characteristics for guiding catheter ablation in patients with repetitive monomorphic ventricular tachycardia (RMVT) originating from the aortic sinus cusp (ASC). BACKGROUND: Repetitive monomorphic ventricular tachycardia can originate from the right ventricular outflow tract (RVOT) and ASC in patients with a left bundle branch block (LBBB) morphology and an inferior axis. METHODS: Activation mapping and ECG analysis was performed in 15 patients with RMVT or ventricular premature contractions. The left main coronary artery (LMCA) was cannulated as a marker and for protection during radiofrequency delivery if RMVT originated from the left coronary ASC. RESULTS: During arrhythmia, the earliest ventricular activation was recorded from the superior septal RVOT in eight patients (group 1) and from the ASC in the remaining seven patients (group 2). The indexes of R-wave duration and R/S-wave amplitude were significantly lower in group 1 than in group 2 (31.8+/-13.5% vs. 58.3+/-12.1% and 14.9+/-9.9% vs. 56.7+/-29.5%, respectively; p < 0.01), despite similar QRS morphology. In five patients from group 2, RMVT originated from the left ASC, with a mean distance of 12.2+/-3.2 mm (range 7.3 to 16.1) below the ostium of the LMCA. In the remaining two patients, the RMVT origin was in the right ASC. All arrhythmias were successfully abolished. None of the patients had recurrence or complications during 9+/-3 months of follow-up. CONCLUSIONS: On the surface ECG, RMVT from the ASC has a QRS morphology similar to that of RVOT arrhythmias. The indexes of R-wave duration and R/S-wave amplitude can be used to differentiate between the two origins. Radiofrequency ablation can be safely performed within the left ASC with a catheter cannulating the LMCA.     

Electrocardiographic patterns of superior right ventricular outflow tract tachycardias: distinguishing septal and free-wall sites of origin

INTRODUCTION: The superior right ventricular outflow tract (RVOT) septum and free wall are common locations of origin for outflow tract ventricular tachycardias (VT). We hypothesized that (1) unique ECG morphologies of pace maps from septal and free-wall sites in the superior RVOT could be identified using magnetic electroanatomic mapping for accurate anatomical localization; and (2) this ECG information could help facilitate pace mapping and accurate VT localization. METHODS AND RESULTS: In 14 patients with structurally normal hearts who were undergoing ablation for outflow tract VT, a detailed magnetic electroanatomic map of RVOT was constructed in sinus rhythm, then pace mapping was performed from anterior, mid, and posterior sites along the septum and free wall of the superior RVOT. Pace maps were analyzed for ECG morphologies in limb leads and transition patterns in precordial leads. Monophasic R waves in inferior leads for septal sites were taller (1.7 +/- 0.4 mV vs 1.1 +/- 0.3 mV; P < 0.01) and narrower (158 +/- 21 msec vs 168 +/- 15 msec; P < 0.01) compared with free-wall sites; lacked "notching" (28.6% vs 95.2%; P < 0.05); and showed early precordial transition (by lead V4; 78.6% vs 4.8%; P < 0.05). A positive R wave in lead I also distinguished posterior from anterior septal and free-wall sites. Based on QRS morphology in limb leads and precordial transition pattern (early vs late), in a retrospective analysis, a blinded reviewer was able to accurately localize the site of origin of clinical arrhythmia (the successful ablation site on the magnetic electroanatomic map) in 25 of 28 patients (90%) with superior RVOT VT. CONCLUSION: Pace maps in the superior RVOT region manifest site-dependent ECG morphologies that can help in differentiating free-wall from septal locations and posterior from anterior locations. Despite overlap in QRS amplitude and duration, in the majority of patients a combination of ECG features can serve as a useful template in predicting accurately the site of origin of clinical arrhythmias arising from this region.     

Dynamic Changes of QRS Morphology of Premature Ventricular Contractions During Ablation in the Right Ventricular Outflow Tract: A Case Report

Electrocardiographic characteristics can be useful in differentiating between right ventricular outflow tract (RVOT) and aortic sinus cusp (ASC) ventricular arrhythmias. Ventricular arrhythmias originating from ASC, however, show preferential conduction to RVOT that may render the algorithms of electrocardiographic characteristics less reliable. Even though there are few reports describing ventricular arrhythmias with ASC origins and endocardial breakout sites of RVOT, progressive dynamic changes in QRS morphology of the ventricular arrhythmias during ablation obtained were rare.This case report describes a patient with symptomatic premature ventricular contractions of left ASC origin presenting an electrocardiogram (ECG) characteristic of right ventricular outflow tract before ablation. Pacing at right ventricular outflow tract reproduced an excellent pace map. When radiofrequency catheter ablation was applied to the right ventricular outflow tract, the QRS morphology of premature ventricular contractions progressively changed from ECG characteristics of right ventricular outflow tract origin to ECG characteristics of left ASC origin.Successful radiofrequency catheter ablation was achieved at the site of the earliest ventricular activation in the left ASC. The distance between the successful ablation site of the left ASC and the site with an excellent pace map of the RVOT was 20 mm.The findings could be strong evidence for a preferential conduction via the myocardial fibers from the ASC origin to the breakout site in the right ventricular outflow tract. This case demonstrates that ventricular arrhythmias with a single origin and exit shift may exhibit QRS morphology changes.     

Electrocardiographic predictors of long-term outcomes after radiofrequency ablation in patients with right-ventricular outflow tract tachycardia.

AIMS: The objectives of this study were to identify electrocardiographic (ECG) predictors of long-term outcomes after radiofrequency (RF) ablation in patients with right-ventricular outflow tract (RVOT) tachycardia. METHODS AND RESULTS: We correlated ECG characteristics with RF ablation outcomes in 144 patients with RVOT tachycardia who underwent RF ablation for >1 year. Unfavourable RF ablation outcomes were predefined as unsuccessful RF ablation or recurrence of tachycardia requiring repeated ablation. RF ablation was not successful in 11 (7.6%) patients and 16 (12%) patients had arrhythmia recurrence requiring repeated ablation. Average follow-up time was 72.2+/-28.4 months. Selected parameters from univariate analysis included number of RF applications, pacemapping, application of bonus burn, procedure time, monophasic R-wave in lead I, QS pattern in leads I and aVL, QRS duration in leads II and V(2), and right axis deviation, in ventricular tachycardia. From logistic regression analysis, only monophasic R-wave in lead I remained in the final equation (P=0.004, odds ratio 12.9). CONCLUSION: Monophasic R-wave in lead I during RVOT tachycardia is associated with unfavourable outcomes after RF ablation. This finding may help clinicians in the selection of patients for RF ablation and for the prediction of RF ablation outcome.     

Electrocardiographic characteristics of the variants of idiopathic left ventricular outflow tract ventricular tachyarrhythmias

Background: Despite similar QRS morphology, idiopathic repetitive monomorphic ventricular tachyarrhythmias (VTs) of left ventricular outflow tract (LVOT) are known to have the variants of different adjacent origins, including the aorto-mitral continuity (AMC), anterior site around the mitral annulus (MA), aortic sinus cusps (ASC), and epicardium. However, the electrocardiographic characteristics of those variants previously have not been evaluated fully.
Methods and Results: Based on the mapping site and successful ablation in 45 consecutive patients with LVOT-VTs, we classified them into VTs of AMC (n = 3), MA (n = 8), ASC (n = 32), and epicardial (n = 2) origins. In all patients, we performed activation mapping and an electrocardiographic analysis. All AMC-VTs patients had monophasic R waves in almost all the precordial leads, while those with anterior MA-VTs had an Rs pattern in some precordial leads except for lead V6, and those with ASC-VTs had a variable transitional zone in leads V1–4. There was no S wave in lead V6 in any group except for one patient with anterior MA-VTs. The intrinsicoid deflection time in the AMC-VTs patients and anterior MA-VTs patients was significantly greater than in those with ASC-VTs (P < 0.05). There was no significant difference in the R-wave amplitude in the inferior leads among the groups. Successful radiofrequency catheter ablation (RFCA) was achieved in all patients except for in those with epicardial origin VT.
Conclusions: Despite many morphological similarities, the LVOT-VTs originating from the AMC, anterior MA and ASC could be identified by our proposed electrocardiographic characteristics in order to safely perform RFCA.