Evaluation of the recurrence of atrial fibrillation after pulmonary venous ablation

OBJECTIVES: The mechanism of the recurrence of atrial fibrillation after pulmonary vein ablation was evaluated. METHODS: Eighty patients with atrial fibrillation underwent pulmonary vein ablation. If extrasystoles or atrial fibrillation initiations were frequent, focal ablation was performed at the site of the earliest activation. If the patient had little or no ectopy, all pulmonary veins with distinct and late pulmonary vein potentials were targeted for pulmonary vein isolation, which was achieved by minimal segmental ablation limited to the ostial site with the earliest pulmonary vein potentials. RESULTS: Focal ablation or pulmonary vein isolation was performed in 42 and 38 patients, respectively. After focal ablation, atrial fibrillation recurred in 23 patients and re-ablation was performed in 10:7 at sites near the previous source, 2 at a different part of the same pulmonary vein, and 1 at a different pulmonary vein. After pulmonary vein isolation, atrial fibrillation recurred in 19 patients and re-ablation was performed in 14:8 due to recovery of atrio-pulmonary vein conduction, 3 at non-pulmonary vein foci, 2 at pulmonary vein ostia proximal to the previous pulmonary vein isolation, and 1 at a different pulmonary vein. CONCLUSIONS: After focal ablation, atrial fibrillation recurred from other foci in the same pulmonary vein or other pulmonary veins. Therefore, three or four pulmonary veins should be isolated. However, atrial fibrillation recurred after pulmonary vein isolation due to the recovery of atrio-pulmonary vein conduction or non-pulmonary vein foci. Further development of new mapping and ablation systems to detect the foci and create a complete lesion at the pulmonary vein ostium may be necessary.     

Effect of atrial overdrive pacing on pulmonary vein focal discharge in patients with atrial fibrillation.

AIMS: Recently, it has been shown that atrial fibrillation may be caused by spontaneously discharging foci located predominantly in the pulmonary veins. However, the effect of atrial overdrive pacing on these pulmonary vein foci has not been studied. METHODS AND RESULTS: In 58 patients with drug refractory paroxysmal or persistent atrial fibrillation we performed radiofrequency catheter ablation of arrhythmogenic triggers inside the pulmonary veins and/or an ostial pulmonary vein isolation with conventional mapping and ablation technology. Continuous bigeminal pattern of discharge from one or more arrhythmogenic pulmonary veins was recorded in 14 patients. Atrial overdrive pacing resulted in suppression of pulmonary vein 'focus' activity in all patients. The longest mean atrial pacing cycle length resulting in overdrive suppression was 587+/-114 ms. Independent of pacing rate and duration, bigeminal pulmonary vein focus activity reemerged 2.5+/-3.7s after cessation of pacing. Overdrive suppression of the pulmonary vein focus was incomplete in 9 pacing attempts, and resulted in induction of atrial fibrillation from the same vein in 3 of 31 pacing manoeuvres. At 2 years follow-up 79% of these patients were free of atrial fibrillation, 55% without antiarrhythmic drugs, 24% on previously ineffective antiarrhythmic drug therapy. CONCLUSION: Stable pulmonary vein 'focus' activity in patients with atrial fibrillation can be suppressed by atrial overdrive pacing. However, 'proarrhythmic' effects of atrial overdrive pacing, such as induction of atrial fibrillation, were also seen.     

Incidence of pulmonary vein stenosis 2 years after radiofrequency catheter ablation of refractory atrial fibrillation.

AIMS: Pulmonary vein ablation offers the potential to cure patients with atrial fibrillation. In this study, we investigated the incidence of pulmonary vein stenosis after radiofrequency catheter ablation of refractory atrial fibrillation by systematic long-term follow-up. METHODS AND RESULTS: Forty-seven patients with refractory and highly symptomatic atrial fibrillation underwent radiofrequency catheter ablation of arrhythmogenic triggers inside the pulmonary veins and/or ostial pulmonary vein isolation with conventional mapping and ablation technology. These patients had follow-up examinations at 2 years with transoesophageal doppler-echo and/or angio magnetic resonance imaging for the evaluation of the pulmonary veins. Seventy-seven percent of the patients were free from atrial fibrillation, 51% were without antiarrhythmic drugs, and 26% were on previously ineffective antiarrhythmic drug therapy. However, 13 of the 47 patients showed significant pulmonary vein stenosis or occlusion. Only three of these 13 patients complained of dyspnoea. Distal ablations inside the pulmonary vein were associated with a 5.6-fold higher risk of stenosis than ostial ablations. CONCLUSIONS: At 2-year follow-up, the risk of significant pulmonary vein stenosis/occlusion after radiofrequency catheter ablation of refractory atrial fibrillation with conventional mapping and ablation technology was 28%. Distal ablations inside smaller pulmonary veins should be avoided because of the higher risk of stenosis than ablation at the ostium.     

Catheter ablation of atrial fibrillation: Radiofrequency catheter ablation for redo procedures after cryoablation

AIM: To evaluate the effectiveness of two different strategies using radiofrequency catheter ablation for redo procedures after cryoablation of atrial fibrillation.METHODS: Thirty patients(paroxysmal atrial fibrillation: 22 patients,persistent atrial fibrillation: 8 patients) had to undergo a redo procedure after initially successful circumferential pulmonary vein(PV) isolation with the cryoballoon technique(Arctic Front Balloon,CryoCath Technologies/Medtronic).The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy(CARTO;Biosense Webster) depending on the intra-procedural findings.After discharge,patients were scheduled for repeated visits at the arrhythmia clinic.A 7-day Holter monitoring was performed at 3,12 and 24 mo after the ablation procedure.RESULTS: During the redo procedure,a mean number of 2.9 re-conducting pulmonary veins(SD ± 1.0 PVs) were detected(using a circular mapping catheter).In 20 patients,a segmental approach was sufficient to eliminate the residual pulmonary vein conduction because there were only a few recovered pulmonary vein fibres.In the remaining 10 patients,a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction.All recovered pulmonary veins could be isolated successfully again.At 2-year follow-up,73.3% of all patients were free from an arrhythmia recurrence(22/30).There were no major complications.CONCLUSION: In patients with an initial circumferential pulmonary vein isolation using the cryoballoon technique,a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation.     

环状标测电极指导下射频消融治疗阵发性房颤的临床分析

目的探讨环状标测电极指导下射频消融治疗阵发性心房颤动的疗效。方法对23例阵发性房颤患者在环状电极指示下行经验性肺静脉和（或）上腔静脉电隔离。结果23例阵发性房颤患者中共隔离肺加上腔静脉87条，左上肺静脉22条，左下肺静脉18条，右上肺静脉22条，右下肺静脉12条，上腔静脉13条，平均每例3．78条。平均操作时间和X线透视时间分别为（148±34）min和（52±9）min。1例发生术中心包填塞，2例行2次手术。平均随访（3．8±1．6）个月，20例无房颤复发，2例有房早发作，成功22例。结论阵发性心房颤动采用环状标测电极指导下射频消融电隔离术对绝大多数患者是有效的，并能改善患者的心功能情况。     

Identification of pulmonary vein foci by non-contact mapping in patients with paroxysmal atrial fibrillation.

AIMS: Ectopies from the pulmonary veins may cause paroxysmal atrial fibrillation and their discrete ablation may be curative. In the absence of focal activity during the procedure, identification of target sites with conventional techniques is difficult. We investigated the feasibility of non-contact mapping (EnSite) for identification and successful ablation of pulmonary vein foci in such cases. METHODS AND RESULTS: We studied 7 patients with idiopathic paroxysmal atrial fibrillation referred for percutaneous ablation and not presenting spontaneous or inducible atrial premature beats during the procedure. An EnSite balloon catheter and an ablation catheter (NaviStar) were placed inside the left atrium. The ablation catheter was also used for electroanatomic mapping (CARTO) of specific sites. Multiphasic pulmonary vein potentials were detected on virtual electrograms and tagged on the non-contact map and confirmed with conventional mapping. The procedural endpoint was elimination or dissociation of the multiphasic potential. Non-contact mapping identified 13 foci of multiphasic potentials in the seven patients (5 foci were initially identified by EnSite), and discrete ablation suppressed 9 of them (69%). Six months later, 4 of the 5 patients in whom all foci were suppressed remain asymptomatic, in sinus rhythm, under no medication. CONCLUSION: In patients with paroxysmal atrial fibrillation and no ectopic activity during electrophysiological study virtual electrograms may complement conventional techniques in detecting hidden pulmonary vein foci and may be used to evaluate ablation efficacy.     

Contemporary approach to ablation of paroxysmal atrial fibrillation

Pulmonary veins have been shown to play an important role in the initiation and maintenance of paroxysmal atrial fibrillation. Seg-mental ostial isolation of the pulmonary veins results in cure in about 2/3 of the patients. This approach does not address non-pulmonary venous triggers of atrial fibrillation or the importance of the left atrium itself. Left atrial circumferential ablation has also been shown to be efficacious in patients with paroxysmal atrial fibrillation. This approach seems to address not only the various triggers of atrial fibrillation but also the left atrial substrate. Recently, a randomized study compared the 2 strategies and showed that left atrial ablation is superior to segmental ostial isolation. This review will highlight the anatomy and electrophysiology of the pulmonary veins, and the possible mechanisms by which they initiate and maintain paroxysms of atrial fibrillation. Segmental ostial isolation of the pulmonary veins and left atrial ablation will be compared as well.     

Curative catheter ablation for atrial fibrillation

Optional statement With the recent advances in the understanding of the mechanisms of atrial fibrillation, radiofrequency catheter ablation has emerged as an effective therapeutic modality for patients with atrial fibrillation. Techniques for catheter ablation evolved from elimination of triggers that often originate within the pulmonary veins and initiate atrial fibrillation, to additional left atrial ablation using a variety of approaches to also eliminate the mechanisms that play a role in perpetuation of atrial fibrillation. With the current ablation strategies, atrial fibrillation can be eliminated in approximately 85% of patients with paroxysmal, and in approximately 70% of patients with chronic, atrial fibrillation with a low incidence of significant complications. In symptomatic patients with paroxysmal or chronic atrial fibrillation who have failed antiarrhythmic drug therapy, catheter ablation is an effective treatment strategy for maintenance of sinus rhythm.     

Radiofrequency ablation of atrial fibrillation

The possibility of curing patients suffering from paroxysmal atrial fibrillation using a radiofrequency ablation treatment is a major change in the management of this arrhythmia. Pulmonary vein disconnection is efficient and safe after a learning curve of the operator. This pulmonary vein isolation is the first and mandatory step allowing disappearance of atrial fibrillation in 70% of the patients. Modification in fibrillatory substrate using linear lesions increases the rate success to 75% in chronic atrial fibrillation and to 82% in paroxysmal atrial fibrillation. The radiofrequency ablation of atrial fibrillation should be considered as a surgical treatment without an open heart, isolating structures and cutting tissues are technical improvements (new radiofrequency catheters) will probably facilitate in the future. Some comparative studies with medical treatment are currently evaluating their efficacy, safety and respective cost and they may lead to a considerable increase in the number of patients who could benefit from these curative treatments.     

Atypical left atrial flutter after intraoperative radiofrequency ablation of chronic atrial fibrillation: successful ablation using three-dimensional electroanatomic mapping

Curative treatment of chronic atrial fibrillation (AF) remains a challenging task for electrophysiologists. Eliminating the initiating triggers by focal radiofrequency ablation in a subset of patients with paroxysmal AF and modifying the maintaining substrate by performing linear lesions within the left atrium in patients with prolonged episodes of AF are among the alternative approaches for management of these patients. Recently, a new intraoperative treatment procedure aimed at eliminating left atrial anatomic "anchor" reentrant circuits by induction of contiguous lesions using radiofrequency energy under direct vision was introduced. However, atypical left atrial flutter may occur during follow-up after intraoperative ablation of AF. These arrhythmias most likely are due to discontinuities in linear lesions; therefore, they can be successfully mapped and ablated in a subsequent percutaneous catheter ablation procedure. We report and discuss the case of a patient who underwent successful intraoperative ablation of chronic AF, but who developed atypical left atrial flutter postoperatively. Three-dimensional nonfluoroscopic electroanatomic mapping revealed a gap in the linear lesion line connecting the left upper and right upper pulmonary vein orifices. Ablation at the exit site of the breakthrough was successful.     

Catheter ablation of paroxysmal atrial fibrillation

Catheter ablation techniques for atrial fibrillation have undergone an extensive evolution, starting with linear lesions in the right, then the left atria before being superseded by ablation of triggers, mainly from the pulmonary veins. We investigate the feasibility and results of combined pulmonary vein and linear ablation utilizing a specific linear lesion connecting the lateral mitral annulus to the left inferior pulmonary vein (left isthmus). METHODS: 115 patients (101 M: 54 +/- 9 years) with paroxysmal atrial fibrillation (7 +/- 5 years) resistant to 4 +/- 1.6 anti-arrhythmic drugs were studied. After electrophysiologically guided disconnection of all four pulmonary veins, the left isthmus line was performed with an irrigated tip catheter. Complete linear block was demonstrated during coronary sinus pacing by local mapping looking for widely separated double potentials and confirmed by differential pacing. Mapping and ablation from within the coronary sinus was performed if an epicardial gap was detected after unsuccessful endocardial radiofrequency delivery. RESULTS: 100% of pulmonary veins were successfully disconnected and the left isthmus line was complete with bi-directional block in 88% after a mean of 22 +/- 12 min of endocardial radiofrequency delivery in 44 patients. In 58 patients, additional radiofrequency delivery was required from within the coronary sinus for 5 +/- 5 min. After a follow-up of 6.5 +/- 2.6 months and a mean of 1.4 +/- 0.6 procedures/patient, 79% were in stable sinus rhythm without antiarrhythmic drugs. CONCLUSION: the left isthmus line is feasible and safe and when performed in addition to pulmonary veins isolation can contribute to an increased success rate.     

药物治疗肺静脉和腔静脉电隔离术后阵发性心房颤动

目的 探讨阵发性心房颤动肺静脉和腔静脉电隔离术后早期复发患者药物治疗方法。方法 阵发性心房颤动患者32例，行肺静脉和腔静脉电隔离术后，均给予美托洛尔治疗，早期复发患者加用普罗帕酮，若仍不能控制心房颤动发作，则给予索他洛尔替代上述两药。结果 美托洛尔加普罗帕酮控制阵发性心房颤动的有效率54％。索他洛尔的有效率达83％。控制心房颤动总有效率92％，未发现严重不良反应。所用剂量小于常规剂量。结论 美托洛尔加小剂量的普罗帕酮，或单用小剂量索他洛尔可有效地控制阵发性心房颤动肺静脉和腔静脉电隔离术后早期复发患者的发作。     

Pulmonary vein dimensions and variation of branching pattern in patients with paroxysmal atrial fibrillation using magnetic resonance angiography

Pulmonary veins are the most frequent origin of focal and paroxysmal atrial fibrillation. Although radiofrequency ablation has been attempted for the treatment of focal and paroxysmal atrial fibrillation, the anatomy of the pulmonary vein is still not fully understood. To investigate the dimensions and anatomical variation of the pulmonary vein in patients with paroxysmal atrial fibrillation, we performed breath-hold gadolinium enhanced magnetic resonance (MR) angiography using a 1.5 T cardiac MR imager (GE CV/i) in 32 patients with paroxysmal atrial fibrillation (61 +/- 8 years old), 11 patients with chronic atrial fibrillation (64 +/- 9 years old), and 26 patients with normal sinus rhythm (55 +/- 15 years old). Three dimensional images of the pulmonary veins were thus obtained, and the diameters of the most proximal portion of the left or right superior pulmonary vein and left or right inferior pulmonary vein were measured. Pulmonary vein branching variations were determined by a visual qualitative analysis by two separate readers' agreements, who were blinded to any clinical information. We focused on the existence of a complex-branching pattern draining into the orifice of four pulmonary veins. Patients with either paroxysmal atrial fibrillation or chronic atrial fibrillation showed larger superior pulmonary veins than those with normal sinus rhythm (mean +/- SD; in the left superior pulmonary vein, 20 +/- 3 mm, 23 +/- 3 mm vs 16 +/- 3 mm, P < 0.05; in right superior pulmonary vein, 19 +/- 4 mm, 19 +/- 2 mm vs 16 +/- 2 mm, P < 0.05). Complex-branching pattern was frequently observed in inferior pulmonary veins in patients with either paroxysmal atrial fibrillation or chronic atrial fibrillation; 25/32 patients with paroxysmal atrial fibrillation, 11/11 patients with chronic atrial fibrillation, compared to 7/26 patients with normal sinus rhythm. Complex-branching patterns were not observed in superior pulmonary veins in any patients in this cohort. CONCLUSION: In patients with paroxysmal atrial fibrillation or chronic atrial fibrillation, significant pulmonary vein dilation occurred mainly in the superior pulmonary veins, while a complex-branching pattern was frequently observed in the inferior pulmonary veins. These MR angiographic findings might be useful when performing radiofrequency ablation procedures and catheter manipulation for the treatment of paroxysmal atrial fibrillation.     

Minimally invasive off-pump pulmonary vein isolation to treat paroxysmal atrial fibrillation

BACKGROUND: Minimally invasive off-pump pulmonary vein isolation to cure paroxysmal atrial fibrillation (PAF) may be an alternative to percutaneous catheter-based procedures. METHODS: Three patients with highly symptomatic lone PAF refractory to medical treatment and having undergone unsuccessful catheter-based ablation underwent pulmonary vein isolation using the Cardioblate BP device with a minimally invasive approach. RESULTS: There were no complications and all patients were discharged in sinus rhythm. Mean ablation time per lesion was 15.2 sec and mean operation time was 118 min. CONCLUSIONS: Irrigated bipolar radiofrequency ablation of the pulmonary veins is safe and can be performed off-pump in a minimally invasive manner.     

Left atrial ablation for atrial fibrillation: creating the "box lesion" with a bipolar radiofrequency device

The maze procedure is the gold standard for the ablation of atrial fibrillation, and the "box lesion" around the pulmonary veins is the most important part of this procedure. We have created this lesion with a bipolar radiofrequency ablator, abandoning the usual use of this device (to achieve bilateral epicardial isolation of the pulmonary veins).From March 2004 through the end of May 2010, we performed surgical ablation of atrial fibrillation in 240 patients. Of this number, 205 underwent operation by a hybrid maze technique and the remaining 35 (our study cohort) underwent the creation of a box lesion around the pulmonary veins by means of a bipolar radiofrequency device. Ablation lines were created by connecting the left atriotomy to the amputated left atrial appendage, with 2 ablation lines made with a bipolar radiofrequency device above and below the pulmonary veins. Lesions were made along the transverse and oblique sinuses by epicardial and endocardial application of a bipolar device. The left atrial isthmus was ablated by bipolar radiofrequency and cryoprobe. No complications were associated with the box lesion: 90% and 89% of patients were in sinus rhythm at 3 and 6 months of follow-up, respectively.By creating a box lesion around the pulmonary veins, we expect to improve transmurality by means of epicardial and endocardial ablation of 1 rather than 2 layers of atrial wall, as in epicardial pulmonary vein isolation. Isolation of the entire posterior wall of the left atrium is better electrophysiologically and renders dissection around the pulmonary veins unnecessary.     

Inducibility of atrial arrhythmias after adenosine and isoproterenol infusion in patients referred for atrial fibrillation ablation

INTRODUCTION AND OBJECTIVES: The identification and ablation of atrial ectopic foci could complement the conventional empirical pulmonary vein approach and may increase the success rate of atrial fibrillation ablation. Although both adenosine and isoproterenol infusion have been reported to induce ectopics, no clear findings on their use during ablation have been published. Our aim was to investigate the utility of these two pharmacologic maneuvers in patients referred for atrial fibrillation ablation. METHODS: The effects of adenosine infusion, isoproterenol infusion, or both were evaluated in 53 patients with refractory atrial fibrillation referred for ablation. Patients were in sinus rhythm during evaluation. RESULTS: Administration of adenosine or isoproterenol induced atrial arrhythmias in 46 patients (87%). Arrhythmia inducibility was similar in those with paroxysmal and those with persistent atrial fibrillation (87% and 86%, respectively). Atrial ectopics alone were induced in 31 patients (65%), atrial tachycardia in four (8%), and atrial fibrillation in 13 (27%). In 10 patients (19%), ectopic foci were located outside the pulmonary veins and subsequently underwent ablation. In 32 of the 46 patients with inducible arrhythmias, only the induced ectopic foci were ablated (mean 1.4 [0.6] targets per patient). The long-term success rate of first procedures was 66%. CONCLUSION: Adenosine and isoproterenol infusion induced atrial ectopics in most patients with drug-refractory atrial fibrillation while they were in sinus rhythm. In almost 20%, the ectopic foci were located outside the pulmonary veins. The effectiveness of induced ectopic-guided ablation observed in our patient series supports the clinical utility of this approach.     

Phased-array intracardiac echocardiography during pulmonary vein isolation and linear ablation for atrial fibrillation

INTRODUCTION: Fluoroscopic imaging provides limited anatomic guidance for left atrial structures. The aim of this study was to determine the utility of real-time, phased-array intracardiac echocardiography during radiofrequency ablation for atrial fibrillation. METHODS AND RESULTS: In 29 patients undergoing pulmonary vein isolation (n = 16) or linear (n = 13) left atrial radiofrequency ablation for atrial fibrillation, intracardiac phased-array echocardiography was used to visualize left atrial anatomy and the pulmonary veins, as well as ablation and mapping catheters during ablation procedures. In the 16 pulmonary vein isolation patients, the mean pulmonary vein ostial diameters measured by venography and intracardiac echocardiography were similar for all veins positions, except that left common pulmonary vein diameters were larger as measured by echocardiography (2.50 +/- 0.29 cm) than by venography (1.79 +/- 0.50 cm, P = 0.001). The ostial diameters measured by echocardiography and venography were not correlated, however (r = 0.23, P = 0.19). As directed by echocardiography, only 1 of 25 circular mapping catheters (4%) used in 16 patients was replaced due to inappropriate sizing of the pulmonary veins. Mean pulmonary vein Doppler flow velocities increased after ablation for left-sided veins but ostial diameters were unchanged. In the linear ablation patients, the entire extent of the linear electrode array could be visualized in only 3 of 52 of catheter positions (6%) in the 13 patients. A portion of the catheter could be seen in only 50% of all target catheter positions. CONCLUSION: Phased-array intracardiac echocardiography (1) allows sizing and positioning of pulmonary vein mapping catheters, (2) provides measures of pulmonary vein ostial diameters, (3) continuously monitors pulmonary vein Doppler flow velocities, and (4) has limited use in positioning linear ablation catheters in the left atrium.     

老年心房颤动不同方式的经导管射频消融治疗

目的研究不同方式经导管射频消融治疗对老年房颤的治疗效果。方法53例房颤患者，男性38例，女性15例，年龄60-83岁。按接受不同的经导管消融方法将上述患者分为3组：消融隔离肺静脉治疗阵发性房颤组20例、消融典型房扑治疗房颤合并房扑组26例、消融房室传导加植入永久性起搏器治疗持续性房颤伴药物难以控制的快速心室率和（或）心力衰竭组7例。结果消融隔离肺静脉组中15例采用环状标测电极导管引导电隔离3～4根肺静脉成功，术后无房颤发作8例（53％），房颤发作明显减少4例（27％）；采用电解剖系统引导下环双侧肺静脉线性消融隔离肺静脉5例，无房颤发作4例（80％）。消融房扑组26例典型房扑均消融成功，随访中15例（58％）无房颤发作，8例（31％）房颤发作较前减少。经导管消融房室传导组7例全部成功，4例行右心室、3例行双心室VVI模式起搏，随访中生活质量和（或）心力衰竭症状明显改善。结论针对不同类型的老年房颤患者采用不同的经导管消融方法可以取得较好的临床效果。     

非接触式球囊标测系统指导阵发性心房颤动个体化消融

目的探讨应用非接触式球囊三维标测系统(EnSite Array)指导下心房颤动(简称房颤)个体化射频消融的临床效果。方法18例阵发性房颤患者,应用EnSite Array三维标测房颤优势电传导部位指导个体化消融,并结合大头电极心房内描记到或虚拟电位显示为碎裂电位区进行消融,消融终点为房颤终止转窦性心律或消融线形成双向阻滞。重复术前电刺激或用异丙上腺素静脉滴注后不能诱发或诱发<30s的房颤。结果首次消融的即时成功率为94.4%(17/18),消融中1例出现心包压塞。15例行左右上肺静脉之间靠顶部心房电学改良消融,11例加左上肺静脉与左心耳之间等部位消融,6例加消融左或/和右房峡部或冠状窦口等部位消融。随访15.3±11.3个月,14例术后不服用抗心律失常药物均无房颤发生,3例房颤复发,1例出现心房扑动发作,中期成功率77.8%(14/18)。结论EnSite Array指导下实时根据房颤优势传导区个体化射频消融,消融靶点灵活、针对性强,消融创伤小,中期效果良好。     

The superior vena cava as a site of ectopic foci in atrial fibrillation

Radiofrequency catheter ablation of ectopic foci that trigger atrial fibrillation has been established as a curative method for patients with symptomatic paroxysmal atrial fibrillation. Although the majority of these foci are located in and around the pulmonary veins, other less common locations have been identified. Recognition that foci can lie outside the pulmonary veins is important for ensuring therapeutic success. The most frequently reported foci of ectopic activity outside the pulmonary veins are in the superior vena cava and the posterior wall of the left atrium. Here we report our experience with the ablation of ectopic foci located in the superior vena cava in patients with symptomatic paroxysmal atrial fibrillation.