Mapping for ventricular tachycardia

Mapping strategies for ventricular tachycardia (VT) have evolved significantly in the past 2 decades. This review discusses mapping techniques that can help in successful VT ablation. The electrocardiogram (ECG) remains a vital component of VT mapping and can help to identify the chamber of origin of VT. The ECG morphology of VT, however, is influenced by orientation of heart and location of the scar. Activation mapping during VT is an important technique that can help in further localization. Care has to be exercised to ensure that small signals are not ignored and far-field signals are recognized. Pace-mapping to mimic the VT is another way to map exit site for scar based reentrant VT or the site of origin of triggered and automatic VT in the absence of structural heart disease. For the latter group, this technique is widely used in determining the site of ablation. It is important to ensure a complete ECG match (12 out of 12 leads) of the pace-map to the clinical arrhythmia in these patients. In patients with structural heart disease, entrainment mapping remains the gold standard for defining the protected isthmus and other components of the VT circuit. Using this technique, successful ablation of reentrant VT can be achieved in 60–90% of patients. In order to perform entrainment mapping, the VT has to be hemodynamically tolerated; this is not the case in 25% of pts with scar based reentrant VT. The development of 3-dimensional mapping systems allows for more anatomically based linear ablation in patients with poorly tolerated uniform VT. Despite these advances, there are still about 10–20% VTs that cannot be ablated successfully with the above described techniques, especially in patients with structural heart disease. Other recent advances such as percutaneous closed chest epicardial mapping technique and cooled tip ablation catheter technology have the potential to enhance mapping and successful ablation of VT.     

射频消融治疗特发性心室颤动的研究

目的:探讨射频消融治疗由室性期前收缩(PVB)触发的特发性心室颤动(VF)的效果。方法:常规心电图和动态心电图记录1例特发性VF患者的平常PVB。心内电生理检查诱导VF后,对触发VF的PVB和平常的PVB进行比较。运用起搏标测法寻找PVB的心室位点并行放电消融。术后每个月随访1次,并行动态心电图检查。结果:心内电生理检查可重复诱导出VF,VF均由触发PVB所诱导,触发PVB由2种形态构成,与平常的PVB不完全相同。起搏标测法确定PVB的位点后,放电消融成功。术后随访至今,患者无VF和晕厥发作。结论:特发性VF患者经射频消融治疗触发PVB可以有效地预防VF发作。     

射频消融治疗室性早搏触发特发性室性心动过速／心室颤动的病例分析

目的探讨射频消融治疗在室性早搏（室早）触发特发性室性心动过速／心室颤动（室速／室颤）中的作用。方法总结3例由室早触发室速／室颤的治疗经验,1例对室早进行射频消融（RF—CA）并植入心律转复除颤器（ICD）,另1例经射频消融未完全消除室早而选择植入ICD,第3例经射频消融成功消除室早,未再发室颤。结果随访2年,3例患者均存活,ICD未再记录到室速／室颤。结论在室早触发室速／室颤病例中,应分析室早与室速／室颤的相关性,给予个体化治疗,射频消融室早可以消除／减少晕厥和室颤的发作。     

导管射频消融治疗特发性室性心动过速的临床应用

目的评价射频消融治疗特发性室速的有效性和安全性.方法收集2002年1月至2005年1月期间在我院进行射频消融的特发性室性心动过速(IVT)患者34例,右室流出道特发性室速(IRVT)采用起搏标测确定消融耙点,左室特发性室速(ILVT)采用激动顺序标测和起搏标测相结合确定消融靶点.结果其中20例起源于左室间隔部和流出道,14例起源于右室流出道;31例即刻成功,3例失败,成功率91.2%.结论射频消融治疗特发性室性心动过速是安全和有效的.     

Catheter ablation for ventricular tachycardia

Sudden cardiac death due to ventricular arrhythmias remains the most common cause of death in developed nations. Implantable cardioverter defibrillators have been shown to improve mortality in high‐risk groups for ventricular tachyarrhythmias, but they are not curative, with the risk of arrhythmia recurrence remaining unaltered. It is also important to remember that ventricular tachycardia (VT) in the setting of a structurally normal heart is often not associated with an increased risk of sudden death and catheter ablation is a potentially curative procedure in this cohort. Recent advances in catheter ablation for VT have increased the efficacy in creating adequate lesions, accurate three‐dimensional maps and mapping haemodynamically unstable VT, all of which have increased the utility of this modality in the treatment of ventricular arrhythmias. In this article, we review the recent advances that have fuelled renewed interest in catheter ablation of VT, its clinical utility and who should be referred.     

导管射频消融治疗室性期前收缩的随访

目的:研究射频消融治疗室性期前收缩的效果。方法:对60例频发、症状明显、药物治疗无效的室性期前收缩患者,根据体表心电图特点初步判断室性期前收缩来源,将大头消融电极置入左心室或右心室,用激动顺序标测及起搏标测法确定消融靶点,以12～40W,3～7min消融。以室性期前收缩在放电后10s内消失,维持稳定窦性心律30min为即刻成功标准。结果:消融即刻成功率95%(57/60)。术后随访(21±15)个月,无消融相关并发症发生。结论:经导管射频消融治疗室性期前收缩安全、有效,可作为症状严重,药物治疗无效或不能耐受患者的治疗选择。     

Catheter ablation for hemodynamically unstable monomorphic ventricular tachycardia

INTRODUCTION: Hemodynamic collapse precludes extensive catheter mapping to identify focal target regions in many patients with ventricular tachycardia (VT) associated with heart disease. This study tested the feasibility of catheter ablation of poorly tolerated VTs by targeting a region identified during sinus rhythm. METHODS AND RESULTS: Ablation was attempted in five patients, ages 44 to 59 years, with left ventricular ejection fractions of 0.15 to 0.20 and poorly tolerated VT causing multiple implantable defibrillator therapies (6 to 30 episodes/month). VT was due to prior infarction in three patients and nonischemic cardiomyopathy in two. Target regions were sought that met the following criteria: (1) evidence of slow conduction from fractionated sinus rhythm electrograms and stimulus-QRS delays during pace mapping, and (2) evidence that the region contains the reentrant circuit exit from pace mapping. In 4 of 5 patients, a target region was identified and radiofrequency lesions applied. Ablation abolished all recurrences of VT in 3 of 4 patients during follow-up of 14 to 22 months. There were no complications. CONCLUSION: Ablation of poorly tolerated VT is feasible in some patients by mapping during sinus rhythm and performing ablation over a region of identifiable scar that contains abnormal conduction and a presumptive VT exit.     

射频导管消融治疗特发性室性心动过速(附20例报告)

目的 特发性室性心动过速(IVT)的射频消融(RFCA)研究。方法共收集20例临床诊断IVT患者,男性14例。女性6例,年龄40.5±12.5(21～66)岁,病史7.8±8.8(1～22)年,心动过速时R—R间期为:309±69(240～430)ms。心动过速时心电图呈右束支传导阻滞(RBBB)型8例。左束支传导阻滞(LBBB)型,且Ⅱ、Ⅲ、avF主波向上12例。对20例患者进行心电生理检查及射频消融治疗。结果 20例均获成功,术后1例起源左心室后间隔,1例起源于右心室流出道之室性心动过速分别于术后第3、7天复发,余无室性心动过速复发,亦无并发症。结论RF—CA治疗IVT成功率高,RFCA关键在于靶点标测和标测方法的选择。     

射频消融治疗起源于左室流出道的非持续性室性心动过速和频发性室性早搏

目的观察左室流出道非持续性室性心动过速（室速）和频发性室性早搏患者的射频消融治疗结果,探讨此类患者的射频消融指证。方法５例患者因非持续性室速和频发性室性早搏而引起明显临床症状,药物治疗无效。采用起搏标测法确定室速和室性早搏的起源部位,并射频消融治疗。结果在升主动脉瓣左窦下方的左室流出道记录到提前（３１±４）ｍｓ的心室激动,起搏心电图１２导联ＱＲＳ波形与室速和室性早搏形态完全相同者４例,１１导联相同者１例,该部位消融后５例患者的室速和室性早搏不被诱发。随访１３±６个月,除１例患者复发,另４例的临床症状明显改善。结论射频消融治疗左室流出道非持续性室速和室性早搏安全有效,但应严格掌握适应证。     

经导管射频消融治疗室性心动过速的疗效观察

室性心动过速是临床上较常见的心律失常,可发生于健康人群和各种心脏病患者。由于其可造成严重的症状甚至危及生命,因而需要积极处理,目前导管射频消融已逐渐成为首选治疗。我院近2年经导管射频消融治疗室性心律失常患者11例,现报道如下,以评价其临床疗效及安全性。     

射频导管消融治疗室性早搏的临床评价

目的探讨射频导管消融治疗室性早搏（室早）的适应证及临床效果.方法对47例右心室流出道（RVOT）室早,5例左心室流出道（LVOT）室早,2例左心室流人道室早,分别采用起搏标测或起搏与激动标测结合的方法进行标测消融.结果消融术成功的有47例,好转的有5例,失败2例.术后随访6个月至5年,仅1例患者在术中诱发心室颤动,经电复律成功.结论射频导管消融治疗室早是一种安全、有效的方法,其适应证可适当放宽.     

射频消融治疗顽固性右心室流出道室性期前收缩

目的 :观察射频消融治疗右心室流出道室性期前收缩 (VPB)的疗效。方法 :12例频发右心室流出道VPB患者 ,动态心电图示VPB数 (2 4 786± 72 2 7)个 /2 4h ,VPB相关的临床症状重 ,服用多种抗心律失常药物无效或不能耐受。采用起搏标测法确定VPB的起源部位 ,行射频消融治疗。结果 :10例起搏标测记录到与自发VPBQRS形态 12导联一致的波形 ,消融成功 ,成功部位在右室流出道间隔部 7例、游离壁 3例。另 2例只记录到 11导联一致的波形 ,消融失败。成功率为 83.3%。成功病例术后 1周复查动态心电图示VPB(2± 3)个 /2 4h ;随访 5～ 15个月 ,复查动态心电图示VPB(4± 11)个 /2 4h ,无复发病例 ,无并发症发生。结论 :导管射频消融治疗右心室流出道VPB疗效好、安全性高 ,可供临床症状重、药物治疗效果不好患者选择