环状电极标测指导射频消融治疗肺静脉起源的阵发性房颤

背景　常规方法标测射频消融治疗局灶性房颤常导致较长的手术时间及较低的成功率。环状电极标测指导射频消融能够克服这些缺点。目的　评价在 10极环状电极标测指导下射频消融电隔离肺静脉治疗阵发性房颤的可行性和有效性。方法　本组研究包括 16例抗心律失常药物治疗无效的阵发性房颤患者 [男性 11例 ,女性 5例 ,平均年龄 (5 1± 14 5 )岁 ]。 10极的环状标测电极在窦性心律或者冠状窦远端 (CSd)起搏的情况下标测肺静脉 ,确定房性早搏发生的起源 ;一旦确定靶肺静脉 ,肺静脉电位的分布及其激动顺序进行评价 ,射频消融在肺静脉口最早激动处进行。消融终点设定为 :①肺静脉电位消失 ;②肺静脉电位与心房电位无关 ;③房早消失。结果　本组研究总共消融了 36条肺静脉 ,包括 16条左上肺静脉 ,12条右上肺静脉 ,7条左下肺静脉 ,1条右下肺静脉。有 2例消融了 1条肺静脉 ;8例消融了 2条肺静脉 ;5例消融了 3条肺静脉 ;消融 4条肺静脉者 1例。手术时间以及X线曝光时间分别为 (186 7± 6 3 8)min及 (5 1 5± 15 0 )min。在随访的 1～ 12月 ,11例 (6 8 7% )在未服抗心律失常药没有房颤发作 ,其中 2例为再次手术 ,有效者 3例 (18 7% ) ,2例未成功 (12 6 % )。初次术后有 2例发作房早 ,其中 1例服用胺碘酮 ,另外 1     

右侧神经丛消融对阵发心房颤动伴窦性心动过缓心率的影响

目的:探讨环肺静脉消融的基础上,进一步进行右侧神经丛消融以观察消融对心率的影响。方法:12例心动过缓伴心房颤动的患者,其中男性9例,女性3例,平均年龄(60.58±9.25)岁,在完成环肺静脉隔离的基础上,进行解剖指导下右侧神经丛的消融。结果:12例均完成四个肺静脉隔离及上腔静脉去神经消融,消融上腔静脉过程中,心率由(72.92±5.30)次/min增加到(84.58±5.63)次/min,术后平均随访(18±8)个月,心房颤动成功率50%。心率由术前(56.67±4.87)次/min,增加到术后1w(68.92±6.20)次/min,术后6个月(65.75±4.09)次/min。心率变异性(SDNN)由术前(132.83±16.7)ms减少为术后1w(87.67±19.21)ms,术后6个月(109.75±18.65)ms。结论:在环肺静脉消融的基础上,进行解剖指导下的上腔静脉消融可以进一步提高心率,达到去迷走神经支配的目的。     

Predictors of success after selective pulmonary vein isolation of arrhythmogenic pulmonary veins for treatment of atrial fibrillation

BACKGROUND: Atrial fibrillation (AF) ablation procedures typically involve isolation of all pulmonary veins (PVs) in addition to adjunctive linear lesions, yet the need for such an extensive ablation strategy in all patients is unclear. OBJECTIVES: The purpose of this study was to identify a subgroup of patients undergoing AF ablation with good clinical success after limited PV isolation. METHODS: Patients (N = 450) underwent trigger-guided segmental isolation of only arrhythmogenic PVs. We compared clinical characteristics of patients who required isolation of only one or two PVs to those in whom AF ablation required isolating > or = 3 PVs. RESULTS: For the group of patients undergoing isolation of < or = 2 PVs, AF freedom without antiarrhythmic drug use was achieved in 56 (58%) of 97 patients, and AF control was achieved in 66 (68%) of 97 patients after a single procedure. After additional procedures, 77 (79%) of 97 patients achieved complete AF freedom without antiarrhythmic drugs, and 82 (85%) of 97 patients achieved AF control. Younger age (odds ratio [OR] 1.05; confidence interval [CI] 1.01,1.09) and lack of persistent AF (OR 3.27; CI 1.0, 10.7) were each independent predictors of freedom from AF. In patients younger than 50 years with paroxysmal AF undergoing isolation of < or = 2 PVs (n = 44), AF freedom without antiarrhythmic drugs was achieved in 32 (73%) of 44 after a single ablation procedure. CONCLUSION: Targeted PV isolation has a good long-term (18-month) success rate in patients younger than 50 years with paroxysmal AF and < or = 2 PVs triggering AF.     

心房神经节消融后心房结构重构与心房颤动诱发的关系

目的研究心房心外膜神经节丛（GP）消融后心房基质的变化,探讨其与心房颤动（房颤）诱发的关系。方法10只犬随机分为假手术组和GP消融组。所有犬均行超声心动图后无菌下右侧开胸,观察右心房短阵快速电刺激诱发房颤情况。之后GP消融组分别消融心房右前和右下GP,消融后即刻观察右心房短阵快速电刺激诱发房颤情况。所有犬喂养8周后,同样方法再观察房颤诱发情况。取出心脏分离左、右心房肌组织,采用放射免疫法检测脑钠肽（BNP）水平及免疫组化法检测神经密度;同样方法检测犬开胸前和开胸后8周血浆BNP水平和超声心动图。结果假手术组和GP消融后即刻右心房刺激未能诱发出房颤,但房颤在GP消融后8周易诱发;血浆和右心房组织BNP水平在GP消融后8周明显升高[（119．5±22．6）pg／mlV8（167．7±26．4）pg／ml,（213．2±34．9）pg／gVS（287．6±36．4）pg／g,P〈0．05],但左心房BNP水平无明显变化;两组犬术前和术后左右心房大小均无明显变化;GP消融8周后右心房GAP43、TH和ChAT阳性纤维的密度低于假手术组,差异有统计学意义[（791±714）permm2vs（2540±863）permm2,（448±582）permm。VS（1855±623）permm2,（580±726）permm2vs（2833±851）permm2,P〈0．05],但左心房无明显变化。结论心房心外膜GP消融后,心房基质发生重构,可能是GP消融后房颤易诱发的原因。     

非肺静脉起源阵发性心房颤动导管消融效果的中长期随访

目的 肺静脉隔离足治疗阵发性心房颤动(房颤)的主要策略.但是部分阵发性房颤患者的房颤为非肺静脉起源.本文对非肺静脉起源阵发性房颤消融效果进行中长期随访研究.方法 入选256例阵发性房颤患者,其中女性62例,平均年龄(53±2)岁,行电生理检查,共发现27例(占10.5%)为非肺静脉起源(非肺静脉起源组),包括起源于上腔静脉(16例,占59.3%),左心房后壁(4例,占14.8%),界嵴(2例,占7.4%),冠状静脉窦(2例,占7.4%),卵圆窝(1例,占3.7%),左心耳(1例,占3.7%),左心房游离壁(1例,占3.7%).其余患者为肺静脉起源组.非肺静脉起源组中,所有病例的触发灶均在初次消融术中成功消融.4例(14.8%)需行2次消融术,其中3例为上腔静脉起源,1例为左心房后壁起源.肺静脉起源组52例(22.7%)需行2次消融术,6例需3次消融术.结果 非肺静脉起源组随访(40±12)个月,有25例(92.6%)无房颤复发,肺静脉起源组随访(44±12)个月,185例(80.8%)无房颤复发.结论 在房颤某些亚群的治疗中,标测并消融非肺静脉起源的触发灶非常重要.而且对于该类病人,中长期的随访证实中长期成功率较高,提示导管消融治疗房颤有较好的中长期治疗效果.     

心内神经丛对快速刺激致犬心房颤动易感性的影响

目的研究心内神经丛对犬心房颤动(房颤)易感性的影响。方法健康成年杂种犬13只,开胸测定心房不同部位不应期(AERP)后,将起搏电极缝于左上肺静脉与左房交界处。其中7只切除右上肺静脉与左房交界处的脂肪垫(去神经组),另外6只不切除脂肪垫(对照组)。以AOO模式600次/min起搏。记录二组犬形成持续性房颤所需要的时间及阵发性和持续性房颤维持的时间。测定二组犬心房有效不应期和不应期离散度。结果二组形成房颤所需时间和房颤持续时间均有显著差别。去神经组形成持续性房颤所需时间长于对照组(120±67h比80±52h,P<0.01)。而且,对照组阵发性和持续性房颤维持的时间均长于去神经组(持续性房颤维持时间为57±39min比42±13min,P<0.01)。房颤后,所有犬各部位AERP均较术前缩短,不应期离散度(dAERP)增大。与对照组相比,去神经组AERP缩短和dAERP的增大更为明显。结论犬心外膜脂肪垫内的心内神经丛对心脏的电生理特征有重要的调节作用,去除这些心内神经丛能延长心房有效不应期,缩小不应期离散度,从而抑制房颤的发生和维持。     

稳心颗粒对心房神经节消融后心房颤动的影响机制

目的 探讨口服稳心颗粒对犬心房神经节（GP）消融后心房颤动（房颤）诱发的影响.方法 19只犬随机分为假手术组、GP消融组和稳心颗粒组.所有犬左侧第4肋间开胸,右心房短阵快速起搏观察房颤诱发情况.假手术组电生理监测后关胸,GP消融组和稳心颗粒组开胸后消融心房左、右GP,所有犬喂养8周,其中稳心颗粒组给予稳心颗粒0.25g·kg-1 ·d-1.8周后再次观察房颤诱发和心房基质变化.结果 与假手术组和稳心颗粒组相比,GP消融组8周后房颤诱发率明显升高.GP消融组犬血浆脑钠钛（BNP）明显增高[（142.2±21.4）pg/ml对（259.3±34.5）pg/ml,P＜0.01],而稳心颗粒组的BNP水平在消融8周后降低,但差异无统计学意义;3组犬在开胸前和喂养8周后血肿瘤坏死因子（TNF-α）和白细胞介素6（IL-6）无明显变化;与假手术组相比,GP消融组8周后左右心房肌组织中的BNP,TNF-α和IL-6水平明显增加,左心房组织的BNP,TNF-α和IL-6水平分别为[（117.1±15.2） pg/mg对（121.3±14.9）pg/mg,P＞0.05; （91.3±35） pg/mg对（180.3±72） pg/mg,P=0.02; （125.3±42） pg/mg对（273.3±83）pg/mg,P＜0.01];右心房组织的BNP,TNF-α和IL-6水平分别为[（143.6±33.7） pg/mg对（206.2±41.4） pg/mg,P=0.02;（75.3 12.1）pg/mg对（141.3±64） pg/mg,P=0.03;（175.1±42.5）pg/mg对（351.7±101）pg/mg,P＜0.01].假手术组和稳心颗粒组心房肌组织中的BNP,TNF-α和IL-6水平差异无统计学意义.结论 长期口服稳心颗粒可抑制心房GP消融后基质重构和房颤的诱发.     

Gradients of atrial refractoriness and inducibility of atrial fibrillation due to stimulation of ganglionated plexi

Introduction . The mechanism(s) whereby atrial ectopy induces atrial fibrillation (AF) is still poorly understood.
Methods and Results . In 12 dogs, we determined the refractory period (RP) along the right atrium (RA) and right superior pulmonary vein (RSPV), and AF inducibility with and without concurrent stimulation of the anterior right ganglionated plexi (ARGP) at the base of the RSPV. Multielectrode catheters were attached to the RSPV and RA with the distal electrodes close to ARGP. The RP and window of vulnerability (WOV), i.e., the longest S₁–S₂ minus the shortest S₁–S₂ at which AF was induced, were measured before and during incremental levels of ARGP stimulation. Mapping of the onset of AF was performed using the EnSite® mapping system (St. Jude Medical, St. Paul, MN, USA) positioned in the RA.
A single premature depolarization (PD) from the RSPV that did not induce AF without ARGP stimulation could do so with ARGP stimulation. The onset of AF consistently arose at the myocardium subtending the ARGP. With GP stimulation, the average WOV at the RSPV-atrial junction was significantly wider than at the RA appendage (65 ± 27 vs. 8 ± 17 msec, P < 0.05) or further along the RSPV sleeve (48 ± 39 vs. 10 ± 20 msec, P < 0.05). Even without GP stimulation, high intensity (10–20 mA) premature stimuli delivered at the RA appendage induced AF, originating from atrial tissue subtending the ARGP, presumably due to axonal conduction that activated the ARGP.
Conclusion . GP stimulation, subthreshold for atrial excitation, converts isolated PDs into AF-inducing PDs, suggesting that autonomic tone may play a critical role in the initiation of paroxysmal AF.     

Morphology and pathophysiology of target anatomical sites for ablation procedures in patients with atrial fibrillation: Part II: Pulmonary veins,caval veins,ganglionated plexi,and ligament of Marshall

The inadequate long-term efficacy of anti-arrhythmic therapy has been one of the main reasons for the development of non-pharmacological interventions for patients with atrial fibrillation such as catheter and surgical ablation. This has greatly increased interest in the functional morphology and electrophysiological properties of the atria and related anatomical structures. This article is the second of a two-part review that aims to provide anatomical and functional details concerning some of the principal anatomical sites commonly targeted by ablative procedures for treating atrial fibrillation, and covers pulmonary veins, ganglionated plexi, caval veins, and the ligament of Marshall. It also provides some general information about site-specific ablation procedures.     

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.     

Prevalence of pulmonary vein disconnection after anatomical ablation for atrial fibrillation: consequences of wide atrial encircling of the pulmonary veins.

AIMS: Anatomical and wide atrial encircling of the pulmonary veins (PVs) has been proposed as a cure of atrial fibrillation (AF). We evaluated the acute achievement of electrical PV isolation using this approach. In addition, the consequences of wide encircling of the PVs with isolation were assessed. METHODS AND RESULTS: Twenty patients with paroxysmal AF were studied. Anatomically guided ablation was performed utilizing the CARTO system to deliver coalescent lesions circumferentially around each PV to produce a voltage reduction to <0.1 mV, with the operator blinded to recordings of circumferential PV mapping. After achieving the anatomical endpoint, the incidence of residual conduction and the amplitude and conduction delay of residual PV potentials were determined. Electrical isolation of the PV was then performed and the residual far-field potentials evaluated. Individual PV ablation was performed in all PVs. Anatomically guided PV ablation was performed for 47.3+/-11 min, after which 44 (55%) PVs were electrically isolated. In the remaining 45%, despite abolition of the local potential at the ablation site, PV potentials [amplitude 0.2 mV (range 0.09-0.75) and delay of 50.3+/-12.6 ms] were identified by circumferential mapping. After electrical isolation (12.2+/-11.7 min ablation), 55 (69%) PVs demonstrated far-field potentials; with a greater incidence (P=0.015) and amplitude (P=0.021) on the left compared with the right PVs. At 13.2+/-8.3 months follow-up, 13 patients (65%) remained arrhythmia-free without anti-arrhythmics. In four patients (20%), spontaneous sustained left atrial macrore-entry required re-mapping and ablation. Macrore-entry was observed to utilize regions around or bordering the previous ablation as its substrate. CONCLUSION: Anatomically guided circumferential PV ablation results in apparently coalescent but electrically incomplete lesions with residual conduction in 45% of PVs. Wide encircling of the PVs was associated with left atrial macrore-entry in 20% of patients.     

起源于肺静脉的阵发性心房颤动导管射频消融治疗

目的　探讨环状电极 (Lasso电极 )标测指导起源于肺静脉的阵发性心房颤动 (房颤 )导管射频消融治疗的安全性和有效性。方法与结果　 2 0 0 1年 5～ 12月 ,12例药物治疗无效的阵发性房颤患者 ,男 8例 ,女 4例 ,平均年龄 (47 8± 14 9)岁 ,行心内电生理检查和射频消融术。在Lasso电极指导下标测肺静脉 ,以确定诱发房颤的房性早搏起源处。确定房性早搏的消融靶点后 ,在有房性早搏或冠状窦远端起搏或右心耳起搏下寻找优势肺静脉电位 (PVP)放电消融 ,或肺静脉口环状消融。消融终点设定为 :①肺静脉电位振幅明显减低或消失 ;②肺静脉自律性电位与心房电活动无关 ;③诱发房颤的房早消失。结果成功隔离 2 6条肺静脉 ;其中左上肺静脉 12条 ,右上肺静脉 8条 ,左下肺静脉 5条 ,右下肺静脉1条。有 2例仅消融 1条肺静脉 ,均为左上肺静脉 ;8例消融2条肺静脉 ,消融 3条与 4条肺静脉者各 1例。术程 (196 4±6 5 8)min ,X线曝光时间 (5 2 0± 14 4 )min。术后随访 2～ 8个月 ,有 1例频发房早发生 ,经口服胺碘酮后房早消失 ;4例有房颤短阵发作 ,其中 3例接受口服药物 (2例服用胺碘酮 ,1例服用索他洛尔 ) ,1例植入有抗房颤程序的DDDR起搏器 ,能够有效抑制房颤发作。术中选择性肺静脉造影发现 6例有轻度肺静脉狭窄 ,其     

环肺静脉消融治疗迷走型和交感型心房颤动的临床疗效观察

目的 分析迷走型和交感型心房颤动(房颤)的临床特点并采用环肺静脉消融进行治疗,对其方法学及疗效进行评价.方法 接受环肺静脉消融的连续192例阵发性房颤患者,根据房颤发作特点分为迷走型房颤组(n=25)和交感型房颤组(n=18),其余病例归为对照组(n=139),对3组病例的临床特点进行分析,采用环肺静脉消融进行治疗达到电隔离,对其疗效进行比较.结果 迷走型房颤多在夜间、休息时或进食后发生,交感型房颤多在白天、运动和情绪激动后发生.前者平均年龄相对年轻[(52±6)岁对(67±4)岁,P＜0.05],环肺静脉消融后随访(21.2±11.4)个月,迷走型房颤组、交感型房颤组和对照组成功率分别为88.0％、83.3％和84.6％,3组成功率差异无统计学意义.结论 迷走型和交感型房颤作为房颤的特殊类型表明自主神经系统参与房颤的发生,采用环肺静脉消融能取得满意的治疗效果.     

三维标测系统和单环状标测导管指示下环肺静脉线性消融电学隔离肺静脉方法学评价

目的探讨三维标测系统和单环状标测导管指示下环肺静脉线性消融电学隔离肺静脉的可行性和有效性。方法2004年5月至2004年11月间我院对68例症状明显、发作频繁、抗心律失常药物治疗无效的心房颤动(房颤)患者进行了在Carto(n=56)或EnSite/NavX(n=12)和单环状标测导管指示下的环肺静脉线性消融肺静脉电隔离术。收集操作过程中的相关数据,计算初始肺静脉电学隔离率、最终肺静脉电学隔离率及并发症资料。结果68例患者共计完成136个环形消融线,操作时间平均为(240±65)min,X线曝光时间平均为(37±12)min。用于左心房重建和环肺静脉线性消融的放电时间分别为(20±9)min和(62±24)min。在完成预定环肺静脉消融线后,初始肺静脉电学隔离率为50.7%(69/136),经寻找缝隙补充消融后最终肺静脉电学隔离率为95.6%(130/136)。70.2%(59/84)的缝隙分布于左侧,29.8%(25/84)见于右侧。并发症包括1例心脏压塞和2例锁骨下及左胸部皮下血肿,均经保守治疗康复,无肺静脉狭窄。结论三维标测系统加单环状标测导管指示下环肺静脉线性消融电学隔离肺静脉成功率高、并发症率低,操作时间及X线曝光时间可以接受。     

去自主神经条件下迷走神经对肺静脉不同部位房颤诱发阈值的影响

目的研究去自主神经条件下迷走神经对肺静脉不同部位房颤诱发阈值的影响。方法于2004年10月至2005年5月对北京大学人民医院心脏电生理室的10只健康杂种犬进行了电生理实验。所有动物均经切断双侧颈迷走神经干和破坏颈交感神经节,建立犬的去自主神经模型。分别在右心耳(RAA)、左心耳(LAA)、左房(LA)和四支肺静脉的近、中、远段行burst刺激,刺激周长S1S1为80ms,脉宽为0.5ms,在仅改变电压刺激强度的情况下,观察迷走神经对肺静脉不同部位房颤诱发阈值的影响。结果当行双侧颈迷走神经刺激时,在心房及肺静脉的所有部位,房颤诱发阈值均有不同程度的下降,且在4支肺静脉的远段表现为差异有显著性(P<0.05和P<0.01),而阿托品则可消除这种变化。结论对于肺静脉起源的房颤,迷走神经不仅参与房颤的维持,而且也可能是参与其起始的重要诱发因素。     

Reversal of pulmonary vein remodeling after catheter ablation of atrial fibrillation

Background Pulmonary veins (PV) and the atria undergo electrical and structural remodeling in atrial fibrillation (AF). This study aimed to determine PV and left atrial (LA) reverse remodeling after catheter ablation for AF assessed by chest computed tomography (CT). Methods PV electrophysiologic studies and catheter ablation were performed in 63 patients (68% male; mean ± SD age: 56 ± 10 years) with symptomatic AF (49% paroxysmal, 51% persistent). Chest CT was performed before and 3 months after catheter ablation. Results At baseline, patients with persistent AF had a greater LA volume (91 ± 29 cm³ vs. 66 ± 27 cm3; P = 0.003) and mean PV ostial area (241 ± 43 mm² vs. 212 ± 47 mm²; P = 0.03) than patients with paroxysmal AF. There was no significant correlation between the effective refractory period and the area of the left superior PV ostium. At 3 months of follow-up after ablation, 48 patients (76%) were AF free on or off antiar?rhythmic drugs. There was a significant reduction in LA volume (77 ± 31 cm³ to 70 ± 28 cm³; P < 0.001) and mean PV ostial area (224 ± 48 mm² to 182 ± 43 mm²; P < 0.001). Patients with persistent AF had more reduction in LA volume (11.8 ± 12.8 cm³ vs. 4.0 ± 11.2 cm³; P = 0.04) and PV ostial area (62 mm² vs. 34 mm²; P = 0.04) than those who have paroxysmal AF. The reduction of the averaged PV ostial area was significantly correlated with the reduction of LA volume (r = 0.38, P = 0.03). Conclusions Catheter ablation of AF improves structural remodeling of PV ostia and left atrium. This finding is more apparent in patients with persistent AF treated by catheter ablation.     

Double multielectrode mapping catheters facilitate radiofrequency catheter ablation of focal atrial fibrillation originating from pulmonary veins

INTRODUCTION: Several reports have demonstrated that focal atrial fibrillation (AF) may arise from pulmonary veins (PVs). The purpose of this study was to investigate the safety and efficacy of using double multielectrode mapping catheters in ablation of focal AF. METHODS AND RESULTS: Forty-two patients (30 men, 12 women, age 65+/-14 years) with frequent attacks of paroxysmal AF were referred for catheter ablation. After atrial transseptal procedure, two long sheaths were put into the left atrium. Two decapolar catheters were put into the right superior PV (RSPV) and left superior PV (LSPV), or inferior PVs if necessary, guided by pulmonary venography. All the patients had spontaneous initiation of AF either during baseline (2 patients), after isoproterenol infusion (8 patients) or high-dose adenosine (2 patients), after short duration burst pacing under isoproterenol (14 patients), or after cardioversion of pacing-induced AF (16 patients). The trigger points of AF were from the LSPV (12 patients), RSPV (8 patients), and both superior PVs (19 patients). The trigger points from PVs (total 61 points) were 18 (30%) in the ostium of PVs and 43 inside the PVs (9 to 40 mm). After 6+/-3 applications of radiofrequency energy, 57 of 61 triggers were completely eliminated, and the other 4 triggers were partially eliminated. During a follow-up period of 8+/-2 months, 37 patients (88%) were free of symptomatic AF without any antiarrhythmic drugs. Twenty patients received a transesophageal echocardiogram, and 19 showed small atrial septal defects (2.8+/-1.2 mm) with trivial shunt. Fifteen defects closed spontaneously 1 month later. CONCLUSION: The technique using double multielectrode mapping catheters is a relatively safe and highly effective method for mapping and ablation of focal AF originating from PVs.