Ensite 3000非接触式球囊标测系统指导右室流出道室性心动过速消融的分析

目的探讨非接触式心内膜标测系统指导右室流出道室性心动过速(RVOT-VT)消融的优势。方法对14例病人,经左股静脉将64极球囊电极及经右股静脉将大头导管置入右心室,En Site 3000系统构建右心室腔三维几何模型,诱发室速或室性早搏,利用虚拟心内膜电图及导航系统进行最早激动点的标测和指导消融。结果 14例病人均诱发及标测到起源于右室流出道的室速或室早,9例起源于右室流出道间隔侧;2例起源于游离壁;1例有3个不同的起源点;1例有一个起源点在中后间隔,另有两个突破口;1例起源下部后间隔与游离壁移行处,突破口在上中间隔。结论 Ensite3000非接触标测系统能缩短手术时间,减少X线对病人及手术医生的损伤。Ensite 3000系统对室速最早激动点的标测和消融更精确、直观和可靠。     

射频导管消融起源于主肺动脉干的室性早搏和/或室性心动过速

目的 探讨起源于主肺动脉干(MSPA)的室性早搏/室性心动过速(室早/室速)的电生理特征、标测方法和导管消融.方法 27例疑似右心室流出道室早/室速的患者中4例(15%)起源于MSPA,其中男性3例,平均年龄(25±10)岁.3例使用非接触式标测系统结合常规标测,1例采用常规标测.2例使用温控导管消融,2例采用冷盐水灌注导管消融.结果 1例(N4)超声心动图提示致心律失常性右心室心肌病,余3例未发现器质性心脏病.1例患者为室早/室速伴有晕厥,另3例仅有室早.室早/室速体表心电图表现为下壁导联R波振幅高、心电轴右偏和QaVL/QaVB比值较大.非接触式标测显示最早激动点位于球囊上方较远距离,激动面积大,最早激动点至爆发点距离远.成功靶点处激动较体表QRS波起始提前(28±6)ms,2例记录到等大的A波和V波,3例记录到融合的尖峰或碎裂电位,局部高能量可以获得较满意的起搏标测图形.4例患者均消融成功,随访(6.5±3.0)个月,1例复发后再次消融成功.结论 起源于MSPA的室早/室速并非少见,非接触式标测的特殊表现可快速揭示诊断,详细的激动标测和起搏标测指导的消融具有较好的临床效果.     

Ensite非接触标测系统在右室流出道室性早搏射频消融中的应用

目的探讨Ensite非接触标测系统指导右室流出道室性早搏(室早)消融的有效性和安全性。方法选取右室流出道室早患者33例,年龄(45±13)岁,其中男12例,女21例。非接触球囊导管经右股静脉至右心室流出道,三维重建心腔。室早时根据虚拟单极电位的等电位图,标测到起源点和突破口分别消融起源点和突破口。结果消融即时成功率为97.0%(32/33),1例失败。1例合并心包积液。快反应方式23例均一次消融成功,慢反应方式10例需2~3次标测消融,成功9例,失败1例。随访6个月,1例复发。结论Ensite心内非接触式标测系统用于右室流出道室早三维标测高效、安全。快反应方式室早起源点和突破口相对固定;慢反应方式室早消融后起源点和突破口常发生改变,需2~3次重新标测消融才成功。     

心肌梗死后室性心律失常电风暴射频导管消融治疗

目的 报道经射频导管消融治疗心肌梗死(MI)后血运重建和抗心律失常药物治疗无效的室性心律失常电风暴2例.方法 2例病人为男性,64岁和73岁.前壁MI后出现反复发作室性心动过速(室速)或心室颤动(室颤),经血运重建、抗心律失常药物等治疗室速、室颤仍反复发作.2例患者室速、室颤均由呈右束支阻滞(RBBB)图形室性早搏(室早)所诱发.标测和消融方法为在左心室内标测室早时最早激动部位后进行射频消融.结果 2例均可记录到频发呈RBBB图形室早,在2例患者中室早均可诱发室速,与临床诱发方式相同.左心室内激动标测显示2例呈RBBB伴心电轴左偏形态的室早的最早激动部位在中下间隔,室早时浦肯野纤维电位提前体表心电图QRS波均为50 ms,窦性心律时在同一部位也可记录到清晰的浦肯野电位,2例分别放电6次和8次,均成功消融室早.2例分别随访49个月和4个月,无室速和室颤复发.结论 MI后室性心律失常电风暴可能由起源于左心室浦肯野纤维网的室早所诱发,经射频导管消融MI后药物和血运重建等治疗无效的电风暴有较好的效果.     

特发性室性心律失常的射频消融

目的特发性室性心律失常（IVA）是指不伴有明显器质性心脏病的室性心动过速（室速）或室性早搏（室早）,约占所有室性心律失常的10％左右。本文系统分析925例IVA病例,探讨IVA的临床、电生理和射频消融的特点。方法本文回顾性分析了从1994年3月至2009年2月,925例IVA患者的临床特点,射频消融治疗的过程和结果。925例病人,男性500例,女性425例,平均年龄（36．65±14．81）岁。临床证实为IVA患者,并且排除了器质性心脏病。在停用抗心律失常药物5个半衰期后,进行电生理检查和射频消融治疗。结果特发性右心室室性心律失常（IRVA）516例,特发性左心室室性心律失常（ILVA）409例,IRVA多发生于女性,发病的平均年龄40岁,大多数表现为频发室早伴有反复单形室性心动过速,出现黑喙症状为14．3％;ILVA多发生于男性,发病的平均年龄33岁,多表现为持续性室速,出现黑矇症状为5．9％。IRVA有486例（94．2％）起源于右心室流出道,而在右心室流出道起源的室速／室早里,又以起源于间隔面的多见,占78％左右,起源于游离壁的占10％左右,其余的12％起源于二者之间的部位。射频消融多采用寻找心内膜最早激动点结合起搏标测来寻找合适的靶点。ILVA最多见的类型是左心室特发室速（ILVT）,有272例（66．5％）,ILVT主要起源于左后分支区域,也可以起源于左前分支区域和临近希氏束部位。主要用激动顺序标测结合浦肯野电位的方法确定消融靶点。IRVA的516例患者射频消融即刻成功率为89．3％。ILVA射频消融即刻成功率为93．7％。结论IVA患者虽然没有器质性心脏病,但是伴有多种临床症状,少部分病人甚至出现黑矇、晕厥,应积极行射频消融治疗,预防出现心室颤动危及生命。     

经导管射频消融室性早搏或室性心动过速治疗心肌梗死后室性心律失常电风暴

目的报道射频消融治疗心肌梗死(MI)后抗心律失常药物治疗无效的室性心律失常电风暴4例,探讨其标测方法和消融效果。方法 4例病人均为男性,64岁、75岁、73岁和60岁。分别于前壁心肌梗死后19天、45天、3天和10天出现反复发作室性心动过速(室速)或室性颤动(室颤),经血运重建、抗心律失常药物治疗室速、室颤仍反复发作。病例1、3、4的单形或多形室速、室颤均有频发室性早搏诱发,病例2植入ICD后服用胺碘酮和β-受体阻滞剂使反复发作的室速暂时得到了控制,但ICD植入一月后室速再次频繁发作。室速均呈右束支阻滞(RBBB)图形伴心电轴左偏。标测和消融方法为在左心室内标测到室早或持续室速时最早激动处后进行射频消融。结果病例1、3、4均可记录到呈右束支阻滞(RBBB)伴电轴左偏和/或右偏形态的室早,在这3例患者中室早均可诱发室速。在频发室早下行标测和消融,激动标测显示3例患者的室早最早激动处在左心室中下部位,室早时浦肯野纤维电位提前体表心电图QRS波40-50ms,且窦性心律时在同一部位可记录到清晰的提前QRS波群的浦肯野纤维电位。3例分别于最早激动处且标测到浦肯野纤维处放电6次、8次和16次,均成功消融室早。病例3因为出现了另一形态的室早,于左室前内侧反复消融5次,另一形态室早亦消融成功。病例2中没有记录到室早,心室程序刺激诱发2种形态室速,呈右束支阻滞(RBBB)图形伴有电轴左偏。在左心室内标测到浦肯野纤维提前室速起始最早60ms处进行消融,成功消融室速。4例分别随访7年、6年、4年和6个月,病例1和病例3无室速和室颤复发,病例2有1次ICD放电,病例4复发室早诱发短阵室速,但无持续性室速、室颤和晕厥发生。结论 MI后频繁快速室性心律失常可能由起源于左室浦肯野纤维网的室早或室速所诱发,经导管射频消融室早或室速对?     

三维标测指导致心律失常性右心室心肌病室性心动过速的射频消融

目的介绍致心律失常性右心室心肌病（ARVC）室性心动过速（室速）的三维标测方法及其消融策略。方法21例ARVC室速患者,因1—4种抗心律失常药物治疗无效,临床上呈反复发作、无休止发作或植入型心律转复除颤器（ICD）植入后频繁放电治疗,接受导管消融治疗。其中,男性19例,女性2例,平均年龄（32±12）岁。9例患者接受电解剖（Carto）标测,12例患者接受非接触标测（EnSite—Array）。在首先明确病变基质的基础上,通过激动标测、拖带标测及起搏标测,分析心动过速的起源、可能的传导径路及其出口以及它们与病变基质的关系。通常于心动过速的出口处及其周边行局灶消融,术中病变基质周边的延迟激动电位应一并消融。结果21例患者,2例呈无休止发作,1例患者表现为频繁室性早搏及加速性室性自主心律,余18例患者消融中共诱发出34种心动过速。所有心动过速均呈左束支阻滞形,平均心动过速周长为（289±68）ms。16例患者（28种室速）消融治疗即刻成功,3例患者（7种室速）部分成功,2例患者（2种室速）消融失败,即刻消融成功率76．2％。所有患者消融术后继续服用抗心律失常药物。平均随访6～30（1d±7）个月,成功患者中2例复发,其中1例再次消融成功;未达即刻成功的5例患者,经抗心律失常药物治疗后,均无室性心律失常事件发生,其中包括1例消融后植入ICD者。结论三维标测系统可首先明确ARVC患者的病变基质,在此基础上结合激动标测和心内各种电刺激技术,可直观显示心动过速的起源、缓慢传导区出口及折返环路,以此制定消融策略可成功治疗ARVC室速。心动过速起源于心肌深部或ARVC病变进展,是消融失败和复发的常见原因。     

EnSiteNavX三维标测系统指导主动脉窦起源的室性心律失常的消融

目的对主动脉窦起源的室性心律失常进行标测和消融需要准确和安全。本研究尝试采用EnSiteNavX标测技术对起源于主动脉窦的室性心动过速（室速）和／或室性早搏（室早）进行消融。方法运用NavX标测系统构建主动脉窦、升主动脉及冠状动脉开口的三维电解剖及激动顺序图,同时进行冠状动脉造影,以确认NavX导航的准确性。结合传统的电生理标测,射频消融治疗24例主动脉窦起源的室早和／或室速。结果24例均射频消融成功,其中,左冠窦内起源16例,右冠窦内起源4例,左、右冠窦问起源4例,术中和术后无并发症。消融时间及x线曝光时间（包括冠状动脉造影时间）分别为（56．1±18．3）min、（11．2±6．8）min。1例患者消融前发现合并左旋支中段狭窄,消融术后成功行支架术。平均随访（16_＋12）个月,1例室速患者有室早复发,再次消融成功。结论NavX标测技术可以代替冠状动脉造影,指导主动脉窦起源的室早和／或室速的标测和消融。     

特发性室性心动过速导管消融治疗的长期疗效观察

目的探讨经导管射频消融治疗无器质性心脏病特发性室性心动过速的近、远期疗效。方法回顾性分析我科2001年6月至2010年10月的13例特发性室性心动过速患者的临床资料,其中男性8例,女性5例,平均年龄40.6±15.6岁。采用激动标测和起搏标测相结合的方法确定室速起源点进行消融,特发性左室性心动过速发作时标测到最早浦肯野电位或舒张晚期电位的部位进行消融。结果心内电生理检查证实:13例室速中右室流出道8例(其中间隔部7例,游离壁1例),左室室速5例(其中4例起源于左后分支,1例起源于左前分支)。12例(92.3%)消融成功,手术操作时间40～166 min,X线曝光时间12～56 min。术后随访2～36个月,有1例(7.7%)左室室速复发。本组病人未出现严重并发症。结论采用导管消融方法治疗特发性室性心动过速安全有效,并发症发生率低,是临床治疗的首选方法。对于定位困难的室速患者,有文献报道非接触式球囊标测系统(Ensite 3000)或Carto三维标测系统指导可以明显提高手术成功率。     

特发性室性心动过速射频导管消融标测方法探讨

目的探讨特发性室性心动过速（IVT）的标测方法.方法对52例行射频消融的IVT患者进行标测.39例源于右心室的IVT采用消融导管右心室起搏标测法,以起搏时与室性心动过速（室速）发作时的12导联心电图QRS波形态与振幅完全相同的起搏部位为消融靶点.12例起源于左心室的IVT以发作时消融电极导管在左心室内标测到较体表心电图QRS波提前≥20 ms的最早高频低振幅电位为消融靶点（激动顺序标测法）,1例左心室室速采用起搏标测法.结果左心室IVT消融成功率100%（13/13）,右心室IVT消融成功率94.87%（37/39）.结论起源于左心室的IVT宜采用激动顺序标测法,起源于右心室的IVT宜采用起搏标测法.     

特发性左室室性心动过速非接触球囊导管系统的标测与消融

介绍非接触球囊导管标测系统 (EnSite 30 0 0系统 )指导难治性特发性左室室性心动过速的标测与射频消融的初步经验。 5例男性病人 ,年龄 33± 17(17～ 6 2 )岁 ,常规方法标测和导管消融失败 2 .4± 1.1(1～ 4)次。常规放置高位右房和右室电生理导管 ,运用置入左室的 6 4极球囊导管和大头电极 ,系统重建三维心内膜几何模型和等电势 ,经右室导管诱发VT ,心动过速周期为 32 3.8± 48.1ms。EnSite 30 0 0系统标测到VT的最早激动点分别位于左后间隔中下部、左侧间隔后下部左束支下方、后下间隔近心尖部、左室后壁近基底部和左后间隔中部。在最早激动点和关键峡部分别行点状、环状和线性消融。 2例患者在心动过速时放电、3例患者在窦性心律时消融 ,均获成功。成功消融靶点处的单极电图均为QS型。X线曝光时间为 2 5± 12min。随访 7.8± 4.6 (1～ 11)个月所有患者均未发作心动过速。结果表明 ,与常规方法比较 ,EnSite 30 0 0系统所建立的心腔三维模拟等电势图可直观地显示心动过速的起源点、传导途径和关键峡部 ,系统模拟的单极腔内电图的形态也有助于判断病灶起源部位及提高消融成功率 ,尤其适用于常规方法消融失败的室性心律失常的标测 ,其独特的导航系统可引导消融导管到达靶点部位指导射频消融 ,并可减少X?     

Radiofrequency catheter ablation guided by noncontact mapping of ventricular tachycardia originating from an idiopathic left ventricular aneurysm

Idiopathic left ventricular aneurysm and diverticulum is known to be an arrhythmogenic substrate associated to ventricular tachyarrhythmias, generally based on a reentry mechanism. A case of a young woman affected by a monomorphic ventricular tachycardia, refractory to medical treatment, originating from an aneurysm of the membranous interventricular septum is reported. The left ventricular aneurysm was well characterized by multislice computed tomography and left ventricular angiography. Because of the nonsustained and poorly tolerated nature of the target arrhythmia, a noncontact mapping system was used to guide radiofrequency catheter ablation, allowing the elaboration of a three-dimensional activation map of the left ventricle on the basis of a ventricular tachycardia single beat. The procedure was acutely successful, and the patient remained free of ventricular tachycardia recurrences without antiarrhythmic drugs during a subsequent 6-month follow-up period. This is the first report of a successful radiofrequency catheter ablation guided by noncontact mapping system of a ventricular tachycardia originating from an idiopathic left ventricular aneurysm. This nonfluoroscopic mapping method allows a reliable reconstruction of the spatial relationships between the left ventricular main cavity and the aneurysm and can be safely and effectively used to map the ventricular tachycardia and guide the ablation procedure, particularly when conventional mapping is not indicated or not effective because of nonsustained or not-tolerated characters of ventricular tachycardia.     

Radiofrequency catheter ablation of various kinds of arrhythmias guided by virtual electrograms using a noncontact, computerized mapping system.

Three-dimensional visualization of cardiac activation has become important for providing further insights into the pathophysiological mechanisms of arrhythmias and to increase the efficacy of catheter ablation. The noncontact mapping system enables a single-beat analysis of the reconstructed geometry of the cardiac chamber. In 8 patients with various kinds of arrhythmias (3 with atrial flutter, 2 with right ventricular outflow tract ventricular tachycardia, 1 with idiopathic left ventricular tachycardia, 1 with atrioventricular nodal reentrant tachycardia and 1 with concealed Wolff-Perkinson-White syndrome), non-contact mapping using an EnSite 3000 system was performed for the guidance of catheter ablation. The optimal sites for successful ablation were detected and all of these arrhythmias were successfully eliminated with the radiofrequency energy applications without any adverse effects. The computerized EnSite 3000 mapping system described here computes accurate isopotential maps that are a useful guide for catheter ablation.     

心腔内超声心动图指导下经导管射频消融治疗左心室后乳头肌室性早搏

目的左心室后乳头肌起源的室性早搏（室早）因其体表心电图与左后分支参与的特发性室性心动过速（室速）一样,都表现为心电轴左偏,伴右束支阻滞合并左前分支阻滞,因此有相当一部分被误认为分支室早。为了明确二者起源点的异同,我们采用术中心腔内超声心动图（ICE）来实时监测消融靶点的确切解剖位置。方法选择3例频发室早患者（男2例,女1例）,平均24h室早30000多次,超声心动图均未见心脏结构异常。在三维电解剖系统（CartoXP）指导下,跨主动脉瓣逆行送入3．5mm冷盐水磁定位标测电极导管于左心室,以激动标测构建左心室内膜图。以室早时提前最多;起搏时能得到12／12导联一致的QRS波以及放电20S内室早逐渐减少和消失作为理想靶点标准。在理想靶点确认后,经ICE确认消融导管在左心室内的确切位置,并记录和分析其局部双极电位图。以既往消融成功的经典左后分支室速作为对照,比较两者之间心电图的异同,为以后的标测和消融提供真实可靠的参照。结果ICE证实该3例室早靶点均位于左心室后乳头肌根部或中段,其解剖位置与左心室特发性室速靶点明显不在同一位置,其消融位点较特发性室速更靠心尖部;其局部双极电位在窦性心律时偶尔也可记录到浦肯野电位,但在早搏时都不能记录到浦肯野电位,说明其为肌源性起源,而特发性室速靶点无论窦性心律下还是室速时均可记录到清晰的浦肯野电位;体表心电图尽管可鉴别的特征不多,但后乳头肌起源的室早较特发性室速胸前导联（V：～V。导联）QRS时限明显增宽（前者平均124ms,后者仅86ms）,R／S≤1移行也早于特发性室速（后乳头肌室早在V,导联移行为R／S≤1,特发性室速在V,导联才移行为R／S≤1）。消融10余小时后,室早复发。1个月时复查动态心电图,24h平均室早10000余次,二尖瓣功能未受到任何影响。结论通过实时ICE证实,后乳头肌室早无论起源位置、体表心电图形态还是局部靶点电图均与特发性室速有区别,这类室早消融效果较差,易复发。如何在增强消融强度、扩大消融范围和避免乳头肌损伤之间找到平衡点是该类室早消融的重点和难点。     

应用非接触球囊导管标测系统指导心动过速的心内膜标测与消融

目的观察非接触球囊导管标测系统指导难治性室性心动过速的标测与射频消融的有效性和优越性。方法5例患者均为男性，平均年龄33.2岁。经股静脉或股动脉置入64极球囊电极和射频消融导管至同一心室，计算机标测系统首先构建心腔的几何构型，然后建立心动过速的腔内等电势图，分析心动过速的最早起源点及折返激动的关键峡部，最终利用计算机导航系统指导消融导管至拟定靶点处进行环状或线形消融。结果5例患者共诱发出6种心动过速，心动过速平均周期为（336.6±42.7）ms。2例特发性左室室性心动过速及1例隐匿性束室纤维患者均消融成功。1例扩张型心肌病患者共有两种心动过速，一种起源于右室流出道，另一种起源于左室间隔部，前者消融成功，后者因导管操作致心动过速持续发作伴血流动力学不稳定而终止手术。1例致心律失常性右室心肌病患者于最早激动点处做环状消融，未获成功。5例患者术中和术后均无并发症发生。随访4个月，所有消融成功患者均未再有心动过速发作。结论非接触性球囊导管标测系统指导心律失常的心内膜标测与消融是安全、有效的，与常规的标测和消融方法比较，该系统有一定的优越性，尤其适用于复杂病例、血流动力学不稳定和非持续性室性心律失常的标测及指导射频消融。     

Mapping and ablation of ventricular tachycardia guided by virtual electrograms using a noncontact, computerized mapping system

OBJECTIVES: The purpose of this study was to describe a computerized mapping system that utilizes a noncontact, 64 electrode balloon catheter to compute virtual electrograms simultaneously at 3,360 left ventricular (LV) sites and to assess the clinical utility of this system for mapping and ablating ventricular tachycardia (VT). BACKGROUND: Mapping VT in the electrophysiology laboratory conventionally is achieved by sequentially positioning an electrode catheter at multiple endocardial sites. METHODS: Fifteen patients with VT underwent 18 electrophysiology procedures using the noncontact, computerized mapping system. A 9F 64 electrode balloon catheter and a conventional 7F electrode catheter for mapping and ablation were positioned in the LV using a retrograde aortic approach. Using a boundary element inverse solution, 3,360 virtual endocardial electrograms were computed and used to derive isopotential maps. An incorporated locator system was used in conjunction with or instead of fluoroscopy to position the conventional electrode catheter. RESULTS: A total of 21 VTs, 12 of which were hemodynamically-tolerated and 9 of which were not, were mapped. Isolated diastolic potentials, presystolic areas, zones of slow conduction and exit sites during VT were identified using virtual electrograms and isopotential maps. Among 19 targeted VTs, radiofrequency ablation guided by the computerized mapping system and the locator signal was successful in 15. CONCLUSIONS: The computerized mapping system described in this study computes accurate isopotential maps that are a useful guide for ablation of hemodynamically stable or unstable VT.     

特发性室性心动过速的射频消融

目的对经射频消融术证实的特发性室性心动过速的病例进行总结分析,探讨室性心动过速的发病状况、心电图特点、消融靶点的确定及消融结果。方法对32例特发性室性心动过速的起源部位和体表心电图进行分析,所有患者在诱发出室性心动过速后进行射频消融治疗,观察特发性室性心动过速的射频消融成功率和复发率,以及它们和消融靶点的关系。结果右室特发性室性心动过速心电图表现为左束支传导阻滞,左室特发性室性心动过速心电图则多表现为右束支传导阻滞。消融靶点的确定右室特发性室性心动过速主要采用起搏标测法,左室特发性室性心动过速主要采用激动顺序标测法。右室流出道室速组在起搏标测起搏ECG和VT时ECG的12导联QRS波完全相同处消融成功率较高。结论室性心动过速发作时的体表心电图可初步估计特发性室性心动过速的起源部位,射频消融术治疗特发性室性心动过速成功率高、并发症少。     

Noncontact mapping to guide ablation of right ventricular outflow tract tachycardia

OBJEWCTIVES: The aim of this study was to determine whether noncontact mapping is feasible in the right ventricle and assess its utility in guiding ablation of difficult-to-treat right ventricular outflow tract (RVOT) ventricular tachycardia (VT). BACKGROUND: In patients without inducible arrhythmia, RVOT VT may be difficult to ablate. Noncontact mapping permits ablation guided by a single tachycardia complex, which may facilitate ablation of difficult cases. However, the mapping system may be geometry-dependent, and it has not been validated in the unique geometry of the RVOT. METHODS: Ten patients with left bundle inferior axis VT, no history of myocardial infarction and normal left ventricular function underwent noncontact guided ablation; seven had failed previous ablation and three had received a defibrillator. All noncontact maps were analyzed by a blinded reviewer to determine whether the arrhythmia focus was epicardial and to predict on the basis of the map whether arrhythmia would recur. RESULTS: The procedure was acutely successful in 9 of 10 patients. During a mean follow-up of 11 months, 7 of 9 patients remained arrhythmia-free. Both patients in whom the blinded reviewer predicted failure had arrhythmia recurrence: one due to epicardial origin with multiple endocardial exit sites and one due to discordance between site of lesion placement and earliest activation on noncontact map. CONCLUSIONS: Mechanisms of ablation failure in RVOT VT include absence of sustained arrhythmia, difficulty with substrate localization and epicardial origin of arrhythmia. In this study, noncontact mapping was safely and effectively used to guide ablation of patients with difficult-to-treat RVOT VT.     

Catheter ablation of ventricular arrhythmias originating in the vicinity of the His bundle: significance of mapping the aortic sinus cusp.

BACKGROUND: There is a close anatomical relationship between the right coronary cusp (RCC) and noncoronary aortic cusp (NCC) and sites recording His bundle (HB) activation in the right ventricle (RV). OBJECTIVE: The purpose of this study was to examine the electrocardiographic and electrophysiological characteristics of ventricular arrhythmias (VAs) that originate near the HB and their potential as predictors of successful catheter ablation sites. METHODS: We studied 147 consecutive patients undergoing successful catheter ablation of idiopathic VAs originating from the ventricular outflow tract of either ventricle or the HB region. RESULTS: In 13 (9%) patients with an origin in the RCC (n = 5), NCC (n = 1), or RV HB region (n = 7), the local RV activation in the HB region preceded the QRS onset. In two VAs originating from the RCC or NCC, failed radiofrequency applications near the HB region in the RV delayed the near-field ventricular electrogram and separated the far-field electrograms before the QRS onset in the HB region. The QRS transition in the precordial leads did not discriminate between an RV origin near the HB and an NCC or RCC origin. A QS pattern in lead aVL might be helpful for predicting an RCC origin. CONCLUSIONS: VAs originating near the HB have similar electrocardiographic and electrophysiological characteristics, regardless of whether the ablation site is in the RV or aortic sinuses because of the close anatomical relationship of these structures and rapid transseptal conduction. When RV mapping reveals an earliest ventricular activation in the HB region during VAs, mapping in the RCC and NCC should be added to accurately identify the site of origin.     

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。