Epicardial mapping and radiofrequency catheter ablation of ischemic ventricular tachycardia using a three-dimensional nonfluoroscopic mapping system

Endocardial radiofrequency catheter ablation of ischemic left ventricular tachycardia has been of variable success due to multiple factors. Two such factors include the location of the reentrant circuit in the deep myocardium or on the epicardial surface and the inherent limitations of fluoroscopy as a guide for target localization. We report a patient in whom successful epicardial mapping and radiofrequency catheter ablation of an ischemic left ventricular tachycardia was performed using pericardial access and the CARTO electroanatomic mapping system.     

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.     

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.     

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。     

Non-contact mapping to guide catheter ablation of untolerated ventricular tachycardia.

AIMS: The role of a novel non-contact mapping system (ESI 3000, Endocardial Solutions) to guide radiofrequency catheter ablation of untolerated ventricular tachycardia was investigated in 17 patients; 11 with prior myocardial infarction, three with arrhythmogenic right ventricular dysplasia, and three with idiopathic dilated cardiomyopathy. METHODS: Twenty-seven monomorphic ventricular tachycardias were induced (mean cycle 320+/-60 ms, range 230-450 ms), mapped for 15-20 s, and terminated by overdrive pacing or DC shock. Off-line analysis of isopotential activation mapping was performed to identify the diastolic pathway and/or the exit point of the ventricular tachycardia reentry circuit. Radiofrequency current was applied to create a line of block across the diastolic pathway or around the exit point. RESULTS: All 27 ventricular tachycardias were mapped with the non-contact system. The endocardial exit point (-7+/-15 ms before QRS onset) was defined in 21/21 postinfarction ventricular tachycardias, in 3/3 arrhythmogenic right ventricular dysplasia and in 1/3 idiopathic dilated cardiomyopathy ventricular tachycardias, respectively. The diastolic pathway (earliest endocardial diastolic activity: -65+/-49 ms before QRS onset) was identified in 17/21 postinfarction ventricular tachycardias, in 1/3 arrhythmogenic right ventricular dysplasia and in 1/3 idiopathic dilated cardiomyopathy ventricular tachycardias, respectively. Catheter ablation was performed in 25/27 ventricular tachycardias (93%) in 15/17 patients (88%): 16/25 ventricular tachycardias (64%) were successfully ablated in 10/17 patients (59%). Catheter ablation was not performed in two patients or proved unsuccessful in five patients. At a follow-up of 15+/-5 months, there was no recurrence of documented ventricular tachycardia in all 10 patients with successful catheter ablation; in two of them a previously non-documented ventricular tachycardia occurred. A high recurrence of ventricular tachycardia was observed in patients with a failed procedure (5/7: 71%). No major complication or death occurred. CONCLUSIONS: Non-contact mapping can be effectively used to map and guide radiofrequency catheter ablation of untolerated ventricular tachycardias. Given the favourable acute and clinical long-term results, this approach proves to be more effective in patients with postinfarction ventricular tachycardias, in comparison to patients with arrhythmogenic right ventricular dysplasia and idiopathic dilated cardiomyopathy.     

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。     

Radiofrequency catheter ablation in recurrent ventricular tachycardia

Catheter ablation by radiofrequency energy was carried out in10 patients with one type of recurrent monomorphic sustainedventricular tachycardia resistant to medical antiarrhythrnicmanagement. Electrophysiological studies before ablation includedactivation and pace-mapping. In all patients, the origin ofthe tachycardia was localized in the left ventricle; in theseptum in six, at the posterolateral wall in three and anterobasalin one. The earliest onset of endocardial activation precedingthe QRS complex during ventricular tachycardia ranged between-45 and -90 ms. Transcatheter ablation was performed with abipolar or quadripolar catheter using a radiofrequency generator(HAT 100, Osypka). No complications occurred during the ablationprocedure. Thereafter, in all patients, the clinical tachycardiawas no longer inducible by programmed stimulation. During afollow-up period of 22 to 32 months including eight patients,the tachycardia recurred in two; one of these patients subsequentlydied suddenly. A third patient had one episode of a new typeof sustained ventricular tachycardia some hours after catheterablation. In the remaining patients, there was no recurrenceof symptctnatic tachycardia under maintainance of the antiarrhythmicmanagement which, prior to ablation had been ineffective. Thus, our preliminary results suggest that radiofrequency catheterablation might be beneficial for these high risk patients.     

Radiofrequency catheter ablation in recurrent ventricular tachycardia

Catheter ablation by radiofrequency energy was carried out in10 patients with one type of recurrent monomorphic sustainedventricular tachycardia resistant to medical antiarrhythrnicmanagement. Electrophysiological studies before ablation includedactivation and pace-mapping. In all patients, the origin ofthe tachycardia was localized in the left ventricle; in theseptum in six, at the posterolateral wall in three and anterobasalin one. The earliest onset of endocardial activation precedingthe QRS complex during ventricular tachycardia ranged between-45 and -90 ms. Transcatheter ablation was performed with abipolar or quadripolar catheter using a radiofrequency generator(HAT 100, Osypka). No complications occurred during the ablationprocedure. Thereafter, in all patients, the clinical tachycardiawas no longer inducible by programmed stimulation. During afollow-up period of 22 to 32 months including eight patients,the tachycardia recurred in two; one of these patients subsequentlydied suddenly. A third patient had one episode of a new typeof sustained ventricular tachycardia some hours after catheterablation. In the remaining patients, there was no recurrenceof symptctnatic tachycardia under maintainance of the antiarrhythmicmanagement which, prior to ablation had been ineffective. Thus, our preliminary results suggest that radiofrequency catheterablation might be beneficial for these high risk patients.     

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。     

特发性室性心动过速射频消融治疗的临床研究

目的 总结17例特发性室性心动过速射频消融方法和结果。方法 左室特发性室速(Idiopathic Left Ventricular Tachycardia,ILVT)16例,右室特发性室速(IdiopathicRight Ventricular Tachycardia,IRVT)1例,15例ILVT采用标测V波前最早浦肯野纤维电位(P电位)方法,1例因室速不能诱发的ILVT和1例IRVT采用起搏标测。射频消融按常规方法进行。结果 射频消融治疗ILVT成功率为87.5％,IL-VT均起源于左室间隔面,有效消融靶点处P电位较体表心电图QRS波起始点提前(29.6±11.2)ms(20～55ms)。IRVT1例射频消融成功,有效消融靶点处起搏时与心动过速时的12导联心电图QRS波形完全相同。无1例出现并发症。结论 射频消融术是治疗特发性室性心动过速的安全有效方法。     

Radiofrequency catheter ablation in recurrent ventricular tachycardia.

Catheter ablation by radiofrequency energy was carried out in 10 patients with one type of recurrent monomorphic sustained ventricular tachycardia resistant to medical antiarrhythmic management. Electrophysiological studies before ablation included activation and pace-mapping. In all patients, the origin of the tachycardia was localized in the left ventricle: in the septum in six, at the posterolateral wall in three and anterobasal in one. The earliest onset of endocardial activation preceding the QRS complex during ventricular tachycardia ranged between -45 and -90 ms. Transcatheter ablation was performed with a bipolar or quadripolar catheter using a radiofrequency generator (HAT 100, Osypka). No complications occurred during the ablation procedure. Thereafter, in all patients, the clinical tachycardia was no longer inducible by programmed stimulation. During a follow-up period of 22 to 32 months including eight patients, the tachycardia recurred in two; one of these patients subsequently died suddenly. A third patient had one episode of a new type of sustained ventricular tachycardia some hours after catheter ablation. In the remaining patients, there was no recurrence of symptomatic tachycardia under maintenance of the antiarrhythmic management which, prior to ablation had been ineffective. Thus, our preliminary results suggest that radiofrequency catheter ablation might be beneficial for these high risk patients.     

反复单形室性心动过速的导管射频消融治疗

目的对18例反复单形室性心动过速的消融情况进行分析,并对消融同形室性早搏根治反复单形室性心动过速的可行性、安全性及有效性进行分析.方法18例患者,男性4例,女性14例,年龄19～45岁.心电图及动态心电图均有频发室性早搏和非持续性室性心动过速.征得患者的知情同意书后,电生理检查和消融一次进行,标测和消融同形的室性早搏,采用起搏标测和激动标测相结合的方法,确定室性心动过速的起源处(消融靶点).靶点定位后进行射频消融,温度50～60度,能量30～40W.即刻成功标准为放电后10 s内同形室性早搏和非持续性室性心动过速消失,且静脉滴注异丙肾上腺素不能诱发,观察30 min窦性心律稳定.随访成功标准为术后动态心电图24h室性早搏少于100个,无室性心动过速发作.结果18例患者起源于右心室流出道17例,其中1例存在2种形态的室性心动过速,分别于肺动脉瓣上及瓣下消融成功.起源于左心室流出道1例,于主动脉瓣上左Valsalva窦内消融成功.即刻成功17例.随访平均(23±14)个月,无心动过速复发16例,复发2例,1例于术后3个月复发,再次消融成功,另1例于术后6个月复发,未接受第2次消融.1例术后出现少量心包积液,经放置引流管后好转,无其他并发症.结论消融同形室性早搏是根治反复单形室性心动过速安全和有效的方法.     

Long-term efficacy of single procedure remote magnetic catheter navigation for ablation of ischemic ventricular tachycardia: a retrospective study

Long‐Term Efficacy of Single Procedure Remote Magnetic Catheter Navigation .
Background: Remote magnetic navigation (RMN) aims to reduce some inherent limitations of manual radiofrequency (RF) ablation. However, data comparing the effectiveness of both methods are scarce. This study evaluated the acute and long‐term success of RMN guided versus manual RF ablation in patients with ischemic sustained ventricular tachycardia (sVT). Methods: One hundred two consecutive patients (age 68 ± 10 years, LVEF 32 ± 12%, 88 men) with ischemic sVT were ablated with RMN (Stereotaxis; 49%) or manually (51%) using substrate and/or activation mapping (Carto) and open‐irrigated‐tip catheters. All received implantable defibrillators or loop recorders. Acute success was defined as noninducibility of any sVT at the end of the ablation procedure and long‐term success as freedom from VT upon follow‐up. Results: There was no difference in the baseline characteristics between the groups. Three patients died in hospital. Acute success rate was similar for RMN and manual ablation (82% vs 71%, P = 0.246). RMN was associated with significantly shorter fluoroscopy time (13 ± 12 minutes vs 32 ± 17 minutes, P = 0.0001) and RF time (2337.59 ± 1248.22 seconds vs 1589.95 ± 1047.42 seconds, P = 0.049), although total procedure time was similar (157 ± 40 minutes vs 148 ± 50 minutes, P = 0.42). There was a nonsignificant trend toward better long‐term success in RMN group: after a median of 13 (range 1–34) months, 63% in the RMN and 53% in the manual ablation group were free from VT recurrence (P = 0.206). Conclusion: RMN guided RF ablation of ischemic sustained VT is equally efficient compared with manual ablation in terms of acute and long‐term success rate. These results are achieved with a significantly reduced fluoroscopy time and shorter RF time. (J Cardiovasc Electrophysiol Vol. 23, pp. 499‐505, May 2012)     

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。     

Successful catheter ablation in a patient with polymorphic ventricular tachycardia

We describe a patient with polymorphic ventricular tachycardia (PVT)/ventricular fibrillation (VF) without organic heart disease who was cured by radiofrequency catheter ablation. The patient was a 65-year-old woman with a 10-year history of recurrent syncope. There was no evidence of organic heart disease, and the QT interval during sinus rhythm was borderline normal (corrected QT interval = 0.45 sec1/2). ECG recording during syncope showed PVT. On one occasion, PVT degenerated into VF. This PVT was always induced by a premature ventricular complex (PVC) originating from the right ventricular (RV) outflow tract. Rapid pacing (220 beats/min) at the site of PVC origin reproduced polymorphic change of the QRS wave on surface ECG that was similar to PVT. This suggests that the PVT originated from a single focus in the RV outflow tract. Catheter ablation was performed at the site of PVC origin. During 18-month follow-up, PVT/VF was not documented.     

Radiofrequency catheter ablation of ventricular tachycardia guided by intracardiac echocardiography.

AIMS: Ventricular tachycardia (VT) frequently has an anatomical substrate. Identification of areas prone to arrhythmogenicity facilitates radiofrequency catheter ablation (RFCA). Furthermore, direct monitoring of complications potentially increases safety of RFCA. The aim of this study was to evaluate the feasibility of guiding RFCA of VT with intracardiac echocardiography (ICE), in order to improve outcome and procedural safety. METHODS AND RESULTS: Eleven patients (age 59 +/- 15 years) with drug-refractory VT of various etiologies were studied. VT mapping and ablation were performed using standard techniques. ICE was performed with a multifrequency (5-10 MHz) phased-array transducer positioned in the right ventricle. Twenty different VTs were treated (CL 352 +/- 120 ms, 2.0 +/- 0.9 VT per patient). LV a- or dyskinesia was identified in all post-infarct patients. In patients with arrhythmogenic right ventricular dysplasia, right ventricular aneurysms and dyskinesia could be identified. In all patients catheter position and tip-tissue contact could easily be monitored with ICE. Procedural success (non-inducibility of hemodynamically stable VT) was achieved in all patients. Complications did not occur. CONCLUSION: ICE is feasible in guiding RFCA of VT of different etiologies. The use of ICE in adjunction with fluoroscopy and mapping procedures will facilitate treatment of VT and may contribute to the safety of the procedure.     

特发性室性心动过速及室性期前收缩的射频消融治疗

目的探讨射频导管消融(radiofrequency catheter ablation,RFCA)治疗特发性室性心动过速(idiopathic ventricular tachycardia,IVT)和室性期前收缩(premature ventricualr contraction,PVC)可行性、必要性和疗效。方法回顾性分析16例IVT、PVC患者采用激动顺序标测和起搏标测法确定室性心动过速(ventricular tachycardia,VT)、PVC的起源部位并行RFCA治疗的资料。结果 3例IVT中2例起源于左室间隔部左后分支的蒲肯野系统,1例起源于右心室流出道(right ventricular outflow tract,RVOT)游离壁,同时合并另一种游离壁起源的PVC,3例消融均成功,1例复发。13例PVC中7例起源RVOT间隔部,3例起源于RVOT游离壁,1例同时存在两种形态PVC(分别起源于ROVT间隔部和游离壁),2例起源于左心室流出道,13例消融成功,1例复发。结论 RFCA治疗IVT及特定部位的PVC是安全、有效且成功率高的一种方法。