CARTO标测指导射频消融治疗非峡部依赖性心房扑动的初步研究

初步探讨非峡部依赖性心房扑动 (简称房扑 )———非典型房扑CARTO标测的方法学和射频消融效果。 4例经电生理标测证实的非典型房扑患者 ,男、女各 2例 ,年龄 2 4～ 5 7岁。 1例为先天性心脏病 (简称先心病 )三房心外科术后 ,1例为慢 快综合征。房扑发作时在右房或左房CARTO标测 ,三维重建右房或左房 ,寻找房扑折返径路的关键峡部区域行线性消融。结果 :3例为右房非峡部依赖性房扑 ,1例消融径线为 2条 ,即三尖瓣环至下腔静脉(IVC)口和右房后外侧至IVC ,1例消融径线为右房前中外侧 ,1例为右房下外侧。 1例左房房扑 ,消融径线位于右上肺静脉口下方至卵园窝。 4例均即时消融成功。随访 8～ 2 4个月 ,有 1例先心病术后房扑复发 ,再次行CARTO标测发现房扑折返环位于左房 ,划线消融未成功。结论 :CARTO标测非峡部依赖性房扑有一定的优势 ,能显示房扑折返环和关键峡部 ,并能指导线性消融     

射频消融治疗房性心律失常

本文报道３ 例房性心律失常的电生理特性及射频导管消融治疗的结果。男２ 例,女１ 例;自律性房速１ 例,折返性房速１ 例,房扑１ 例为普通型。对房性心动过速于心动过速发作期采用双大头标测定位以寻找最早激动点;而对普通型房扑则在其折返环的狭部即缓慢传导区进射频电流发放。３ 例均获成功。房扑患者术后第４ 年复发。结果表明,成功消融房性心动过速的关键在于最早激动点的标测定位,采用双大头法标测可以缩短手术时间提高成功机会;消融狭区治疗房扑也是切实可行的,但存在房扑再复发的问题。     

存在自发疤痕心房扑动患者的电生理特征及消融预后

目的:探讨存在自发疤痕的心房扑动(房扑)患者的电生理特征及消融效果。方法:对我科2014-2016年行电生理检查及射频消融的房扑患者进行筛查,所有房扑消融患者消融前均行冠状动脉(冠脉)造影或冠脉CTA检查,进一步行心脏电生理检查,并在三维电解剖指导下行射频消融。消融前行电激动标测及电压标测。共12例房扑患者标测到自发疤痕,其中7例右房房扑于右房标测到自发疤痕,5例左房房扑于左房标测到自发疤痕。结果:右房房扑组疤痕占总心房比例显著高于左房房扑组[(11.1±11.7)%∶(7.8±2.8)%,P0.05]。右房房扑组消融急性成功率为85.7%,左房房扑组为100%,两组差异无统计学意义。随访中,3例右房房扑患者房扑复发,第2次电压标测提示疤痕较前增加;1例左房房扑患者复发,未见疤痕增加;3例右房房扑患者出现窦房结功能障碍,需行永久起搏器植入,左房房扑患者无起搏器植入者。结论:自发疤痕可能成为心房扑动的机制,但也可能为旁观者。与左房房扑比较,存在自发疤痕的右房房扑可能进展至窦房结导致病窦综合征,需安置起搏器。     

经导管射频消融心房扑动

经导管射频消融心房扑动2例,均使持续性心房扑动终止并不能再诱发.本文根据Ⅰ型房扑的右房折返环机制,免去术前心房内标测,直接在低位右房间隔区域放电消融,2例病人分别在第6次放电和第1次放电时房扑终止,并不能再诱发,射频消融术全过程分别为80和60分钟,随访5个月和1周均无任何心动过速复发.本研究表明经导管射频消融术可能为难治性心房扑动提供新的治疗选择.     

射频导管消融治疗Ⅰ型心房扑动

近来研究证实,Ⅰ型房扑的折返环路位于右房,其缓慢传导区位于右房房间隔下后方。在该区进行直流电消融治疗房扑的复发率较高。作者通过心内膜激动标测和拖带起搏标测确定临界区,以施行射频消融治疗房扑。方法与结果全组12例患者,男性7例、女性5例,年龄21～73岁。病史中证实为Ⅰ型房扑(心电图表现为P_(Ⅱ、Ⅲ)aVF倒置,Ⅰ,Ⅴ_(?)双相,Ⅴ_(?)直立),房扑周期为253±39msec。通过标准静脉导管技术进行右房心内膜激动标测及拖带起搏标测,     

射频消融心房扑动拖带刺激的电生理特征

探讨射频消融心房扑动 (简称房扑 )拖带刺激的电生理特征 ,更好的理解房扑机制 ,以期提高消融成功率、减少复发率。 5例阵发性典型房扑患者 ,诱发房扑后 ,在高位、低位右房 ,冠状窦口 (CSO)及右房下部的峡部分别进行拖带刺激 ,分析心房激动顺序 ,然后进行三尖瓣环至下腔静脉之间的线性消融。 5例房扑折返环均为逆钟向旋转 ,峡部 ,高位、低位右房及CSO呈现隐匿拖带 ,左房和卵圆窝呈现显性拖带 ,平均放电 9± 6次 ,均达到右房峡部双向阻滞。CSO起搏时体表心电图Ⅱ、Ⅲ、aVF导联P波形态发生改变。结论 :隐匿、显性拖带对判断峡部依赖性逆钟向房扑有较高价值 ,CSO起搏时心内电图激动顺序和体表心电图P波改变可做为判断峡部消融达到双向阻滞的标志     

导管射频消融治疗先天性心脏病外科术后房性心动过速分析

目的总结先天性心脏病(简称先心病)患者外科术后房性心动过速(简称房速)的电生理机制、导管射频消融方法及结果。方法入选先心病外科术后房速患者,首先行电生理检查明确房速起源心腔。之后在三维标测系统(CARTO或EnSite-NavX)指导下行靶心腔的电解剖标测,明确房速机制后对大折返关键峡部或局灶房速的最早激动点进行消融。结果共入选26例,诱发出30种心动过速,其中单纯为三尖瓣峡部依赖性心房扑动(简称房扑)13例;单纯右房疤痕折返房速4例;右房疤痕房速合并房扑6例,其中3例为两者同时存在形成"8"字折返,3例为两者先后出现;单纯局灶性房速2例;合并有疤痕折返及局灶两种机制的1例。首次消融手术成功率96.2%(25/26),随访(38±23)个月,有6例患者复发。共经三次消融后,总体手术成功率88.4%(23/26)。结论先心病外科术后的房速以三尖瓣环大折返房扑最为常见,其次为游离壁大折返;总体而言,射频消融成功率较高。     

应用CARTO系统射频消融儿童快速右房房性心律失常的初步体会

目的　初步总结应用CARTO系统指导射频消融儿童快速右房房性心律失常的经验。方法　右房房速（AT）3例,典型房扑（AF）l例,心动周期(277±31)ms,在心动过速时应用CARTO系统标测右房,重建三维电解剖图并指导射频消融靶点;房扑消融后分别在低位右房和冠状窦以500ms起搏作电解剖图,判断完全双向传导阻滞。结果　2例为局灶性房速,起源点分别在希氏束旁（Koch三角）和高位右旁;1例为右房壁疤痕介导的折返性房性心动过速(IART)。4例成功消融,放电次数(10.6±5.5)次,透视时间(18±9)min,术程(110±38)min。结论　(1)CARTO系统容易寻找最佳靶点;(2)房扑消融后在低位右房和冠状窦起搏作电解剖图,判断完全双向传导阻滞,大幅度减小X线透视时间,提高成功率,降低复发率。     

心房扑动的心电生理特点及射频消融治疗

目的探讨心房扑动（房扑）病例电生理特点及采用射频消融治疗房扑的效果。方法对２６例房扑患者标测心房激动顺序，用隐匿拖带方法确定折返环部位。用长导引鞘作支撑，在心房内行线性消融方法治疗房扑。结果２６例房扑中２３例折返环位于三尖瓣环部位，１例位于右心房游离壁部位，１例位于左心房，另１例在三尖瓣环及右心房游离壁部位各有一折返环。对２０例临床上有房扑病史者行射频消融治疗，１７例成功。典型房扑１５例（包括１例有２个折返环的房扑），１４例消融成功；不典型房扑６例，４例消融成功。结论房扑的大折返环可采用心房激动顺序及隐匿拖带的方法确定其部位。用长导引鞘作支撑行线性消融是治疗房扑的安全有效的方法。     

无三维空间定位系统监测下线性射频消融治疗MRAT 11例疗效观察

目的观察无三维空间定位系统监测下经瘢痕区至上、下腔静脉线性消融治疗大折返性房速（MRAT）的临床效果。方法对11例右心房内大折返性房速患者采用隐匿拖带方法确定折返环所在区域,并在其相邻瘢痕区附近多点行拖带标测确定激动沿该瘢痕区折返,从瘢痕区至上腔或下腔静脉行线性射频消融。结果 11例存在14个折返环,位于游离壁11例、房间隔3例;其中8例线性消融后转为窦性心律,1例消融中房速转为房扑,消融房扑后心房静止,植入永久起搏器,2例失败;平均随访2.3 a,无相关并发症发生,1例复发、经再次线性消融后房速终止。结论对多数MRAT患者采用隐匿拖带及瘢痕区标测的非三维空间定位方法确定房速折返环部位,进行从瘢痕区至上、下腔静脉的线性消融治疗效果较好。     

Radio-frequency ablation of arrhythmias following congenital heart surgery

BACKGROUND: Cardiac arrhythmias as a late complication following congenital heart surgery are encountered more and more frequently in clinical practice. The use of new electrophysiological methods of visualisation and mapping improves the efficacy of radio-frequency (RF) ablation of these arrhythmias. AIM: To assess patterns of atrial arrhythmias following congenital heart surgery and to examine the efficacy of RF ablation using the electro-anatomical CARTO system. METHODS: Electrophysiological diagnostic study and RF ablation were performed in 24 consecutive patients (mean age 36+/-18 years) who had atrial arrhythmias following congenital heart surgery. The mechanism of arrhythmia (ectopic or reentrant) and strategy of RF ablation procedure were based on the results of the right atrial map performed during index arrhythmia. RESULTS: The patients were divided into five groups according to the type of congenital heart surgery. The ASD group consisted of 17 patients who had undergone in the past surgery due to atrial septal defect, four patients had a history of surgery due to ventricular septal defect (VSD group), and one patient each had undergone surgery due to corrected transposition of the great arteries (ccTGA), tetralogy of Fallot (TF) or dual-outflow right ventricle (DORV). During diagnostic electrophysiological study typical atrial flutter (AFL) was diagnosed in nine patients from the ASD group, atypical AFL in three ASD patients, and ectopic atrial tachycardia (EAT) in six ASD patients. In one patient EAT was induced after ablation of typical AFL. Of the VSD patients, three had atypical AFL, and one had typical AFL. The patient following surgery for ccTGA had atypical AFL and EAT, whereas in the two remaining patients (DORV and TF) atypical AFL was demonstrated. The efficacy of the first session of RF ablation was 83% and no complications were observed. The efficacy of RF ablation of typical AFL was 90%, atypical AFL 78%, and EAT 86% (NS). During the long-term follow-up (24+/-17 months) arrhythmia recurrences were noted in 2 (10%) out of 20 patients who were effectively treated during the first RF ablation session. CONCLUSIONS: Reentry is the most common electrophysiological mechanism of incisional tachycardias, followed by ectopic atrial tachycardia. RF ablation using the electro-anatomical CARTO system is effective and safe in this group of patients.     

导管射频消融Ⅰ型心房扑动的方法学评价

比较在心房扑动 (AFL)时、冠状静脉窦口 (CSO)或低外侧右房 (LRA)起搏下和窦性心律 (简称窦律 )下消融Ⅰ型AFL的优缺点。 48例阵发性AFL随机分为AFL消融组、起搏消融组和窦律消融组 ,对下腔静脉口和三尖瓣环之间的后峡部作线性消融 ,终点为后峡部双向传导阻滞。比较三组患者的电生理参数、急性成功率和远期效果。结果 :三组均达到后峡部双向阻滞 ,随访 2 1.8± 5 .6个月无AFL复发。AFL消融组在AFL终止后均不能达到后峡部双向阻滞 ,需继续在起搏下消融。起搏消融组的操作和曝光时间、放电能量和次数小于其他两组 (P <0 .0 5 )。三组在后峡部双向阻滞后记录局部心房双电位的阳性率为 37.5 %。结论 :①对Ⅰ型AFL采用窦律消融法、起搏消融法和AFL消融法都能取得满意的近远期疗效。②后峡部双向传导阻滞是保证近远期疗效的重要消融终点。③在消融部位标测到双电位可作为消融有效的指标 ,但不能代替后峡部双向阻滞作为消融终点。④起搏消融法的操作和曝光时间、放电能量和次数明显少于在AFL和窦律下消融 ,可作为常规方法使用     

Reentry mechanisms and ablation of ECG-typical atrial flutters involving the cavo-tricuspid isthmus and the proximal coronary sinus

Aim

Reentry circuits of a rare typical atrial flutter (AFL) involving the cavo-tricuspid isthmus (CTI) and proximal coronary sinus (CS) are described based on electrophysiological data and effects of radiofrequency (RF).

Methods and results

Twelve patients with ECG-typical AFL in whom entrainment demonstrated that CTI and proximal CS were both part of the circuit were included. Initial RF target was CTI in 8 patients and proximal CS in 4. Success was defined as AFL termination/noninducibility. After CTI ablation, AFL cycle length (CL) increased in all: AFL persisted in 3, while in the other 5 AFL was interrupted but subsequently induced with the same morphology; before induction CTI bi-directional block was validated; success was obtained at the CS, targeting fragmented atrial potentials (APs). In those with first ablation at CS, AFL was interrupted in 3 with no AFL inducibility; in 1 AFL persisted with CL prolongation and was terminated at CTI. Two reentry patterns were identified: in 5 patients the inter-atrial septum as well as the mid-distal CS were outside of the circuit, while the CTI, proximal CS and Bachmann's bundle zone were inside, suggesting a left atrial component; in 1 patient electrophysiological mapping suggested an intra-CS circuit component. RF was successful in all without recurrence.

Conclusion

Electrophysiological mapping and RF effects suggest a continuum between the CTI and proximal CS in rare cases with ECG-typical AFL. RF inside the proximal CS, targeting fragmented APs, should be considered in any patient in whom CTI ablation failed to interrupt a typical AFL.     

Successful radiofrequency catheter ablation of common atrial flutter at the bottom of a coronary sinus diverticulum

We describe a patient who underwent radiofrequency (RF) catheter ablation of cavo-tricuspid isthmus-dependent atrial flutter (AFL). Extensive ablation at the isthmus failed to terminate the AFL. A coronary sinus (CS) diverticulum arising from the proximal portion of the middle cardiac vein was found near the isthmus. An RF energy application at the bottom of the CS diverticulum resulted in completion of a bidirectional block line at the isthmus, as well as AFL termination.     

Successful Radiofrequency Ablation of Atrial Flutter Causing Hemodynamic Instability in a Patient with Recent Myocardial Infarction

Atrial flutter (AFL) is a common arrhythmia which may decrease cardiac output and may cause embolic events. Direct current (DC) cardioversion, medical cardioversion and radiofrequency (RF) ablation are therapeutic options, but over all RF ablation therapy has the longest event free period. Although development of AFL after myocardial infarction is quite common it may spontaneously recover or results in atrial fibrillation. Herein we report a patient with medical and electrical cardioversion resistant AFL which developed in the early post-myocardial infarction period causing hemodynamic instability, who was successfully treated with RF catheter ablation.     

Randomized comparison of the continuous vs point-by-point radiofrequency ablation of the cavotricuspid isthmus for atrial flutter.

BACKGROUND: Achievement of complete conduction block in the cavotricuspid isthmus (CTI) is a curative ablation technique in patients with common atrial flutter (AFL). The present study was a prospective comparison of the efficacy of 2 ablation strategies in patients with common AFL: the continuous and point-by-point radiofrequency (RF) delivery techniques. METHODS AND RESULTS: Forty patients with common AFL were randomly assigned to either a group treated with a continuous RF delivery or to a group undergoing point-by-point RF ablation. In the first group, the RF energy was continuously delivered during a slow drag of the catheter tip from the tricuspid annulus to the inferior vena cava without stopping the application. In the second group, the RF ablation was performed using a point-by-point approach for 60 s at each point. All patients underwent ablation with an 8-mm-tip ablation catheter with a power limit of 50 W and a target temperature of 55 degrees C. Complete CTI conduction block was achieved in all patients. The patient characteristics, including the anatomy of the CTI estimated by 3-dimensional computed tomography, were no different between the 2 groups. The procedure time (time from the start of RF delivery to the completion of CTI block), fluoroscopic time and total RF energy required to create the CTI block between the continuous and point-by-point groups were 7.3+/-5.6 vs 21.2+/-22.2 min (p<0.01), 7.2+/-4.4 vs 16.2+/-14.1 min (p<0.05), and 15,631+/-6,001 vs 24,072+/-16,140 joules (p<0.05), respectively. There were no complications or recurrences of AFL during the follow-up period in any of the patients. CONCLUSION: In the curative treatment of common AFL, the continuous RF delivery approach could shorten the procedure and fluoroscopic time and reduce the total RF energy compared with the point-by-point RF ablation approach.     

Effect of right atrial isthmus ablation on the occurrence of atrial fibrillation: observations in four patient groups having type I atrial flutter with or without associated atrial fibrillation

BACKGROUND: The goal of this study was to test the hypothesis that the occurrence of atrial fibrillation (AF), in at least some patients with coexisting type I atrial flutter (AFL), is based on macro-reentry around the tricuspid valve orifice, including the right atrial (RA) isthmus, by evaluation of AF recurrences after successful ablation of AFL. METHODS AND RESULTS: Eighty-two consecutive patients with type I AFL, with or without concomitant AF, underwent radiofrequency ablation (RFA) of the RA isthmus by an anatomical approach. The results were analyzed in 4 groups of patients: group 1 (only AFL; 29 patients), group 2 (AFL >AF; 22 patients), group 3 (AF >AFL; 15 patients), and group 4 (developing AFL while receiving class IC antiarrhythmic drug therapy for AF, the "class IC atrial flutter"; 16 patients). In all groups, RFA of type I AFL was performed with a high (>/=93%) procedural success rate. In group 1, only 2 patients (8%) had AF after (18+/-14 months) AFL ablation. These figures were 38% (20+/-14 months) and 86% (13+/-8 months) in groups 2 and 3, respectively. Group 4 patients (4+/-2 months) had a 73% freedom of AF recurrences with continuation of the class IC agent. CONCLUSIONS: The low incidence of new AF during long-term follow-up after RFA of type I AFL makes it unlikely that radiofrequency lesions promote the development of AF. The impact of isthmus ablation on AF recurrences differs according to the clinically predominant atrial arrhythmia and suggests a possible role of the RA isthmus in the occurrence of AF in some patients. Ablation of class IC atrial flutter in patients with therapy-resistant AF is a novel approach to management of this patient subset. Careful classification of AF patients plays a role in the selection of the site of ablation therapy.     

Effect of radiofrequency ablation of atrial flutter on the natural history of subsequent atrial arrhythmias

Introduction: Patients with atrial flutter (AFL) treated medically are at high risk for subsequent development of atrial fibrillation (AF). Whether curative radiofrequency ablation of AFL can modify the natural history of arrhythmia progression is not clear. We aimed to determine whether ablation of AFL decreases the subsequent development of AF in patients without previous AF. Methods and Results: Patients with AFL as the sole atrial arrhythmia were selected from patients who underwent successful AFL ablation at Mayo Clinic between 1997 and 2003 (N = 137). The cohort was divided by presence (n = 50) or absence (n = 87) of structural heart disease. A control group comprised 59 patients with AFL and no history of paroxysmal AF, who received only medical therapy. Occurrence of AF after AFL ablation was compared among study groups and controls. Symptomatic AF occurred in 49 patients during 5 years of follow‐up after AFL ablation, with similar frequency in both study groups. The cumulative probability of paroxysmal and chronic AF was similar in controls and each study group. By multivariate analysis, the AFL ablation procedure carries significant risk of AF occurrence during follow‐up. Fifty patients discontinued antiarrhythmic drugs after AFL ablation, and the rate of cardioversions decreased. Conclusion: Successful ablation of AFL does not improve the natural history of atrial arrhythmia progression; postablation AF is frequent. This suggests that AFL may be initiated by bursts of AF and that in the absence of AFL substrate the AF continues to progress.     

Clinical study of the efficacy of a cooled-tip catheter ablation system for common atrial flutter.

BACKGROUND: Radiofrequency catheter ablation (RF-CA) of common atrial flutter (AFL) requires the creation of a transmural incision to create a bidirectional conduction block in the cavotricuspid isthmus (ITH). METHODS AND RESULTS: RF-CA of the ITH using a cooled-tip system was carried out in 40 patients. In the 'conventional' mode (CONV) of the system, RF energy was applied for 2 min with the temperature set at 60 degrees C and power of up to 50 W, and in the failed cases the 'cooled-tip' mode (COOL) was utilized at 45 degrees C with up to 30 W (with a 15 ml/min saline flow rate). Of the 40 patients, 29 crossed over from the CONV to the COOL after a failed ablation of the AFL. As a result, in all 40 patients a complete linear incision could be created with either the COOL or the CONV, resulting in the successful abolition of the AFL. Complete bi-directional block was successfully created in all patients. No significant side effects occurred. CONCLUSIONS: The COOL was found to be more effective and just as safe as the CONV for AFL ablation, thus facilitating the rapid and complete elimination of the AFL.