Catheter Ablation of the Atrial Origin of a Decrementally Conducting Atriofascicular Accessory Pathway by Radiofrequency Current

Radiofrequency Ablation of Pseudo-Mahaim Fibers. Introduction: A young woman with refractory recurrent supraventricular tachycardia was referred for catheter ablation. Methods and Results: Electrophysiologic studies revealed the mechanism of tachycardia to be atrioventricular (AV) reentry, utilizing a decrementally conducting atriofascicular accessory pathway as the anterograde limb of the circuit and the normal intraventricular conducting system as the retrograde limb. Pace mapping in the right atrium during sinus rhythm suggested an atrial origin of the accessory pathway several centimeters distant from the AV node. Multiple radiofrequency lesions at the distal insertion of the accessory pathway in or near the right bundle branch failed to abolish preexcitation. In contrast, radiofrequency current applied to the ventricular side of the anterolateral tricuspid ring, adjacent to the atrial origin of the accessory pathway, was successful in abolishing preexcitation and inducible supraventricular tachycardia without affecting AV nodal conduction. Conclusion: Radiofrequency ablation can provide curative therapy for intractable supraventricular tachycardia due to decrementally-conducting atriofascicular accessory pathways. The risk of AV block in such patients as a consequence of the procedure should be quite low.     

Demonstration of Retrograde Conduction over an Atriofascicular Accessory Pathway

Atriofascicular Pathway with Retrograde Conduction. Introduction : Absence of retrograde conduction over a right atriofascicular accessory pathway causing reciprocating tachycardia has been considered a hallmark of this clinical entity.
Methods and Results : This report describes successful catheter ablation in a patient presenting with the distinctive pattern of preexcited left bundle branch block tachycardia utilizing a right atriofascicular accessory pathway. This pathway, however, exhibited the unique capability of ventriculoatrial conduction. Both anterograde and retrograde conduction were characterized by "node-like" properties.
Conclusion : Demonstration of retrograde accessory pathway conduction in this particular setting does not exclude the diagnosis of a single, atriofascicular accessory pathway.     

Radiofrequency Catheter Ablation in Unusual Mechanisms of Atrial Fibrillation:

RF Catheter Ablation in AF. Introduction: The purpose of this study was to test the feasibility of radiofrequency (RF) catheter ablation of localized mechanisms of atrial fibrillation (AF).
Methods and Results: Three patients underwent RF catheter ablation for drug-resistant atrial arrhythmias. The first two patients had either incessant atrial tachycardia or AF. In the first patient, the KCG pattern of AF was mimicked by a very rapid atrial focus, whereas in the second patient, AF was due to true degeneration of the atrial activity triggered by atrial tachycardia. In both patients, the ablation of atrial focus led to the clinical disappearance of AF. The third patient had frequent episodes of AF, which lasted several days or weeks, and two documented episodes of atrial flutter. Mapping during AF showed an irregular atrial rhythm in the atrial septum, particularly in the region surrounding the coronary sinus, whereas the entire lateral right atrial free wall exhibited a constantly organized rhythm. RF energy was applied between the tricuspid ring and both the inferior vena cava and the coronary sinus, resulting in inability to reinduceatrial flutter or sustained AF. A 6-month follow-up in this patient showed the disappearance of prolonged episodes of AF.
Conclusion: The observations indicate that AF may be linked to "focal" mechanisms that can be treated by RF catheter ablation.     

房束旁道的电生理特点与Mahaim电位在射频导管消融中的意义

探讨房束旁道的电生理特点与Mahaim电位在射频导管消融 (RFCA)中的意义。 1997年 7月至 2 0 0 3年 1月对 3例拟诊为房束旁道引起的逆向型房室折返性心动过速的患者进行了电生理检查和RFCA。男 2例 ,女 1例 ,年龄分别为 18,2 3,2 5岁。心动过速发作史 7～ 16年 ,频率 180～ 2 30次 /分 ,发作时均有明显心悸 ,其中 1例伴头晕、胸闷。窦性心律时心电图 1例正常 ,另 2例示轻微预激。食管心房调搏与心房程序刺激均易诱发心动过速 ,心动过速时体表心电图呈宽QRS波形。 3例均在三尖瓣环右后侧壁标测到的Mahaim电位处 ,于窦性心律及心房起搏下放电消融。 2例彻底阻断旁道前向传导 ,另 1例反复放电未阻断旁道 ,但重复术前程序刺激心动过速不再诱发。分别随访 5年、2年、6个月心动过速均未复发。结论 :RFCA治疗房束旁道介导的心动过速安全有效 ,Mahaim电位在RFCA中具有重要指导价值。     

Mahaim纤维的电生理特征和导管射频消融

探讨Mahaim纤维的电生理特征和导管射频消融的可行性。 1996年 5月至 1999年 4月对 4例拟诊为Mahaim纤维引起的逆向型房室折返性心动过速的病人进行了电生理检查和射频导管消融。男 3例、女 1例 ,年龄 31± 19岁 ,心动过速发作史 15± 14年 ,频率 2 0 1± 17(180～ 2 2 0 )次 /分 ,发作时均有明显的心悸症状。 4例窦性心律时心电图除 1例轻微预激外均正常。心房程序电刺激可以诱发心动过速。心室起搏时从房室结逆传 ,静脉注射ATP 2 0mg室房分离。 4例Mahaim心动过速均只有前传并呈递减传导特性。 1例同时合并房室结折返性心动过速。 2例导管操作发生心房颤动并经过Mahaim纤维前传 ,1例持续发作、1例短暂发作。 4例分别在心房起搏、心动过速和心房颤动时三尖瓣心房侧标测和消融。心室预激较体表V1导联QRS波起始处提前 40± 6 (34～ 46 )ms处消融均获成功 ,1例靶点位于右前侧壁、3例位于右后侧壁。能量 35± 5W ,消融 5± 3次 ,X线透视时间 38± 2 1min。无手术相关的并发症。合并房室结折返性心动过速 1例同时作了慢径改良。分别随访 3个月～ 3年无 1例心动过速复发。临床研究证实 ,导管射频消融是治疗Mahaim介导的心动过速的有效、可行和安全的方法     

Radiofrequency Ablation of a Mahaim Fiber Following Localization of Mahaim Pathway Potentials

Mahaim Fiber Ablation. We report radiotfrequency ablation of a Mahaim fiber in a patient with wide complex supraventricular tachycardia. Pathway potentials from the lateral aspect of the right AV groove were recorded, which were distinct from the His potential. During atrial pacing, decremental properties of the fiber were demonstrated, which resulted in prolongation of the interval between the atrial electrogram and the Mahaim pathway potential. The pathway potentials, preexcitation, and tachycardia disappeared after a single application of radiofrequency energy, after which the patient has remained free of palpitations. Mapping of a Mahaim fiber by identifying pathway potentials thus allowed accurate localization and successful ablation with minimal energy. We therefore suggest that, where possible, recording of such Mahaim potentials may be the optimal technique for Mahaim liber localization.     

经导管射频消融治疗局灶性心房颤动

报道19例局灶性心房颤动（简称房颤）射频消融治疗的结果,其中药物治疗无效且发作频繁（＞1次／日）的阵发性房颤17例、慢性房颤2例。17例患者尚同时合并有频发房性早搏（简称房早）（动态心电图显示＞700个／日）。同步记录高位有房、冠状静脉窦及左、右上肺静脉电图。根据房早或房颤开始发作时的心房激动顺序确定异位兴奋灶部位,以局部双极电图较体表心电图P'波起点最提前处为消融靶点。成功标准为消融后6Omin内房早／房颤消失及随访期内可以无须药物而维持窦性心律。结果：92．6％（25／27）的异位兴奋灶位于肺静脉,其中尤以双上肺静脉居多（21／25）。随访2．4±3．7个月后有13例患者（68．4％）达上述成功标准,其房早数目由术前的3720±2741个／日降至216±139个／日,除1例发生心房穿孔外无其他严重并发症。结论：射频消融治疗局灶性房颤效果较好,可以作为药物治疗无效的阵发性房颤患者的治疗选择。     

Catheter Ablation with Radiofrequency Energy: Biophysical Aspects and Clinical Applications

Radiofrequency Catheter Ablation. Radiofrequency catheter ablation techniques are becoming increasingly accepted as the therapy of choice for selected patients with symptomatic arrhythmias. The ability to titrate the power output using radiofrequency current has allowed these ablative techniques to be applied safely in a variety of arrhythmias. In many institutions, radiofrequency catheter ablation has now become standard therapy for controlling medically refractory atrial arrhythmias using atrioventricular (AV) junction ablation and for curing AV nodal reentrant tachycardia and supra ventricular tachycardia due to accessory AV connections. This technology is also being used to treat some forms of ventricular tachycardia such as bundle branch reentry ventricular tachycardia, ventricular tachycardia in structurally normal hearts, and with limited success in patients with ventricular tachycardia and coronary artery disease. Advancements in catheter design and energy delivery systems may further expand the use of this form of therapy. (J Cardiovasc Electrophysiol, Vol. 3, pp. 173–186, April 1992)     

持续性心房颤动经导管射频消融治疗的方法探讨(附三例报告)

探讨经导管射频消融治疗持续性心房颤动 (简称房颤 )的可行性。 3例房颤患者房颤持续时间 2个月至 1年4个月。术前口服胺碘酮 ,1例转为窦性心律伴频发房性早搏 (简称房早 ) ,1例转为房早与短阵房颤和阵发心房扑动 (简称房扑 ) ,1例转为房早与阵发房性心动过速 (简称房速 )。经导管作点状消融或点状消融加房扑线性消融 ,2例术中房早消失 ,1例房早显著减少 ,经快速心房刺激或静脉点滴异丙肾上腺素均不能诱发房颤。 1例术后有短阵房颤发作 ,服用莫雷西嗪 ,房颤未再发作。结论 :某些持续性房颤用药物后可转复成窦性心律伴频发房早、房扑或房速 ,局部单点消融或单点消融加线性消融可以达到治疗目的。     

经导管心房除颤在射频消融术中的应用

报道 9例心房颤动 (简称房颤 )患者在射频消融术中用经导管心房同步电除颤的结果。其中有房颤发作史者 5例 ,余 4例为心内电生理检查时诱发。房颤发作时采用普通电生理导管及消融导管在冠状窦与右心耳间放电。9例成功转复为窦性心律 ,平均放电 2 .2次 ,复律成功所需功率为 8.5 6± 4.95J。除 1例需 2 0J转复为窦性心律患者感轻度胸痛外 ,其余仅有心脏轻度震动感。所有患者均未用镇静剂 ,无并发症发生。     

房室折返性心动过速合并阵发性心房颤动的射频导管消融策略

目的探讨房室折返性心动过速（AVRT）合并阵发性心房颤动的射频导管消融（下称消融）策略。方法对经电生理检查证实的AVRT患者15例行旁道消融术,其中男性9例,女性6例,并对术后心房颤动的转归进行12～36个月的随访,观察心房颤动发生、持续时间、有无心律失常等情况。结果13例未再发生心房颤动,2例有严重器质性心脏病的患者仍有阵发性心房颤动复发,但发作次数明显减少,口服胺碘酮可控制症状。1例动态心电图示频发房性期前收缩。结论AVRT与阵发性心房颤动发生率增高密切相关,AVRT是心房颤动的触发因素。旁道消融后,阵发性心房颤动可明显改善,未改善者与心房扩大等心房基质未改善有关。     

Case Report: Spontaneous Atriofascicular Pathway Automaticity Simulating Ventricular Tachycardia

Atriofascicular pathways most commonly present electrocardiographically as an antidromic reciprocating AV reentrant tachycardia. We report the case of a child who presented in infancy with a wide QRS complex tachycardia thought to be supraventricular tachycardia with aberrant conduction, associated with tachycardia-induced cardiomyopathy. Later in life the same patient represented with episodes of palpitations secondary to a wide QRS complex tachycardia, thought to be ventricular tachycardia. Electrophysiologic mapping demonstrated the origin of the wide QRS complex tachycardia was from automatic activity originating from a right anterolateral atriofascicular pathway, which also participated in a reentrant antidromic AV reciprocating tachycardia. Radiofrequency ablation of the atriofascicular pathway successfully eliminated both arrhythmias. The mechanism of the wide QRS complex tachycardia appeared to result from spontaneous automaticity of the atriofascicular pathway.     

New Electrophysiologic Features and Catheter Ablation of Atrioventricular and Atriofascicular Accessory Pathways:

Catheter Ablation for Mahaim Pathways. Introduction : Several modalities of catheter ablation have been proposed to eliminate Mahaim pathway conduction. However, limited research has been reported on the electrophysiologic nature of this pathway in its entity.
Methods and Results : In seven patients, electrophysiologic study was performed, and radiofrequency energy was applied to investigate the electrophysiologic clues for successful ablation. In all seven patients, the Mahaim pathway was diagnosed as a right-sided atriofascicular or atrioventricular pathway with decremental properties. In two patients, two different kinds of electrograms were recorded through the ablation catheter positioned at the Mahaim pathway location: one was suggestive of conduction over the decremental portion, demonstrating a dulled potential; and the other of nondecremental conduction, demonstrating a spiked potential. All but one of the Mahaim pathways were eliminated successfully at the atrial origin where the spiked Mahaim potential was recorded. Radiofrequency energy application was performed at the slow potential site resulting in failure to eliminate the conduction over the Mahaim pathway. Conduction block at the site between the slow and fast potential recording sites was provoked by intravenous administration of adenosine, concomitant with a decrease in the amplitude of the Mahaim potential. In one patient, the clinical arrhythmia was a sustained monomorphic ventricular tachycardia originating from the ventricular end of the Mahaim fiber.
Conclusion : The identification of Mahaim spiked potentials may be the optimal method to permit their successful ablation. Detailed electrophysiologic assessment is indispensable for successful ablation of tachycardias associated with Mahaim fibers because tachycardias unassociated with Mahaim fibers can occur despite complete elimination of the Mahaim fiber.     

利用单极标测在心房颤动时消融显性房室旁道

对12例预激综合征患者在心房颤动时以单极标测指导消融房室旁道，其中左侧显性旁道9例、右侧显性旁道3例。在消融成功的靶点图上，单极标测的心室激动较体表心电图QRS波群显示预激成分最明显的Delta波平均提前46±7ms。全部病例消融成功。平均随访7．9±5．1个月，除1例右侧旁道4个月后恢复旁道前向传导需再次消融外，其余11例常规和动态心电图既未见Delta波，也无房室折返性心动过速和心房颤动发生。结果提示对于心房颤动合并显性房室旁道的患者，采用单极标测，其图形易于迅速辨认、测量方法亦简单，用以指导消融成功率高。     

射频导管消融术治疗房性心动过速23例分析

目的：分析房性心动过速（房速）的电生理特点,探讨射频导管消融术在房速治疗中的价值。 方法：对２３例房速患者进行心电生理检查和射频导管消融治疗。 结果：２３例患者中,２０例为折返性房速,３例为自律性增高性房速。２３例患者,２１例消融成功,其中１９例成功靶点位于右心房,２例位于左心房。成功靶点 ＰＡ为－６０～－２５ ｍｓ,平均－３６ ｍｓ。 结论：射频导管消融术是治疗房速的安全有效的方法。     

Catheter Ablation of Arrhythmia During Pregnancy

Cardiac arrhythmia as a complication of pregnancy can be problematic to maternal health and fetal life and development. Catheter ablation of tachyarrhythmias during pregnancy has been successfully performed in selected patients with limited experience. Techniques to limit maternal and fetal radiation exposure, including intracardiac echo and electroanatomic mapping systems, are particularly important in this setting. Specific accommodations are necessary in the care of the gravid patient during catheter ablation.     

影像学检查在心房颤动射频导管消融术的应用进展

射频导管消融术已成为临床心房颤动的一线治疗方案,充分的术前和术后评估对提高手术的成功率及减少并发症有重要价值.近年来,随着各类新的影像学方法的出现及原有影像学技术的不断发展,心房颤动消融的围手术期评估体系呈现多元化态势.熟悉及准确地运用影像学检查,在指导患者选择、术前准备及预后判断中起着不可替代的作用.     

Radiofrequency Ablation of Ventricular Fibrillation and Multiple Right and Left Atrial Tachycardia in a Patient with Brugada Syndrome

Brugada syndrome is a well-known form of idiopathic ventricular fibrillation (VF). Few data suggest that this arrhythmia may be triggered by ventricular premature beats (VPBs), and an association with other arrhythmia such as monomorphic ventricular tachycardia (VT) or supraventricular tachycardia (SVT) has been reported. In a highly symptomatic 18-year-old-male patient with this syndrome, frequent episodes of VF, fast polymorphic VT, and fast monomorphic sustained regular tachycardia were observed. The tachycardia episodes were classified as VT or VF and as a consequence received appropriate therapies with the implanted cardioverter defibrillator (ICD). Precipitating VPBs that were stored in the ICD memory and on the electrocardiogram (ECG) exhibited the same morphology as frequent isolated VPBs. During the electrophysiological study, right and left atrial tachycardia (AT) with one-to-one atrioventricular conduction were also induced and successfully ablated. VF was ablated using the same noncontact mapping (NCM) system triggering VPBs from right ventricular outflow tract (RVOT).