Clinical outcome of very late recurrence of atrial fibrillation after catheter ablation of paroxysmal atrial fibrillation

INTRODUCTION: High recurrence rate is still a major problem associated with ablation of paroxysmal atrial fibrillation (AF). Most of the recurrences occur within 6 months after ablation. The characteristics of very late recurrent AF (>12 months after ablation) have not been reported. METHODS AND RESULTS: Two hundred seven patients with drug-refractory AF underwent successful focal ablation or isolation of AF foci. After the first ablation procedure, Holter monitoring and event recorders were used to evaluate symptomatic recurrent AF. A second ablation procedure was recommended if the antiarrhythmic drugs could not control recurrent AF. During long-term follow-up (mean 30 +/- 11 months, up to 51 months), 70 patients had recurrent AF, including 13 patients (6%) with very late (>12 months) recurrent AF (group 1) and 57 patients (28%) with late (within 12 months after ablation) recurrent AF (group 2). Group 1 patients had a significantly lower incidence of multiple (> or = 2) AF foci (23% vs 63%, P = 0.02) than group 2 patients. In addition, the incidence of antiarrhythmic drugs use (38% vs 84%, P = 0.001) to maintain sinus rhythm after the first episode of recurrent AF was significantly lower in group 1 than group 2 patients, and the incidence of a second intervention procedure (8% vs 35%, P = 0.051) tended to be lower in group 1 than group 2 patients. CONCLUSION: The incidence of very late recurrent AF after ablation of paroxysmal AF is very low, and the clinical outcome of patients with very late recurrent AF is benign.     

Pulmonary vein electrogram characteristics in patients with focal sources of paroxysmal atrial fibrillation

INTRODUCTION: The major source of ectopic beats initiating paroxysmal atrial fibrillation (AF) is from pulmonary veins (PVs). However, the electrogram characteristics of PVs are not well defined. METHODS AND RESULTS: Group I consisted of 129 patients with paroxysmal AF. Group II consisted of 10 patients with a concealed left-sided free-wall accessory pathway. All group I patients had spontaneous AF initiated by ectopic beats, including 169 ectopic foci originating from the PVs. We analyzed PV electrograms from the 169 ectopic foci during sinus beats and ectopic beats. During AF initiation, most (70%) ectopic beats showed PV spike potential followed by atrial potential; 16% of ectopic beats showed PV fragmented potential followed by atrial potential; and 14% showed fusion potentials. The coupling interval between the sinus beat and the ectopic beat was significantly shorter in the inferior PVs than in the superior PVs (171 +/- 48 msec vs 222 +/- 63 msec, P = 0.001) and was significantly shorter in the distal foci than in the ostial foci of PVs (206 +/- 52 msec vs 230 +/- 56 msec, P = 0.01). The incidence of conduction block in the PVs during AF initiation was significantly higher in the inferior PVs than in the superior PVs (12/24 vs 37/145, P = 0.03) and was significantly higher in the distal foci than in the ostial foci of PVs (43/121 vs 6/48, P = 0.04). The maximal amplitude of PV potential was significantly larger in the left PVs than in the right PVs, and the maximal duration of PV potential was significantly longer in the superior PVs than in the inferior PVs during sinus beats in both group I and II patients. CONCLUSION: PV electrogram characteristics were different among the four PVs. Detailed mapping and careful interpretation are the most important steps in ablation of paroxysmal AF originating from PVs.     

Morphologic remodeling of pulmonary veins and left atrium after catheter ablation of atrial fibrillation: insight from long-term follow-up of three-dimensional magnetic resonance imaging

INTRODUCTION: Understanding the structural remodeling and reverse remodeling of the left atrium (LA) and pulmonary vein (PV) after radiofrequency ablation of atrial fibrillation (AF) may provide important insights into the mechanism and management of AF. This study used magnetic resonance angiographic (MRA) images to investigate changes in PV and LA morphologies before and more than 1 year after ablation. METHOD AND RESULTS: Forty-five patients (36 men and 9 women, mean age 60 +/- 13 years) who underwent MRA before and more than 12 months (mean 21 +/- 11) after ablation of paroxysmal AF were included in the study. The patients were divided into two groups: group I included 35 patients without AF recurrence, and group II included 10 patients with late (>1 month postablation) recurrence of AF. The sizes of the LA and nonablated PV were compared before and after ablation. In group I, significant reduction of ostial area of both superior PVs was noted (left superior PV: from 2.85 +/- 0.67 to 2.59 +/- 0.73 cm2; right superior PV: from 2.89 +/- 0.85 to 2.60 +/- 0.73 cm2, both P <0.001). Geometric alteration toward a round shape was noted in the ostia of superior PVs during follow-up (eccentricity of right superior PV and left superior PV decreased from 0.31 +/- 0.10 to 0.22 +/- 0.13 and from 0.27 +/- 0.11 to 0.19 +/- 0.13, respectively, both P <0.01). However, LA volume showed only borderline reduction (from 61.52 +/- 19.06 to 56.64 +/- 17.13 mL, P=0.05). In group II, significant dilation of the LA (from 61.14 +/- 17.54 to 78.73 +/- 25.27 mL, P=0.004) and right superior PV (from 3.41 +/- 1.12 to 4.08 +/- 1.31 cm2, P=0.016) was noted during follow-up. Ostial area and eccentricity of the left superior, left inferior, and right inferior PVs and LA were similar before and after ablation. CONCLUSION: Structural remodeling of the superior PVs and LA can be reversible after successful ablation without AF recurrence; however, late recurrence of AF is associated with progressive LA dilation.     

Incidence and predictors of very late recurrence of atrial fibrillation after ablation

Introduction: Radiofrequency catheter ablation can effectively treat patients with refractory atrial fibrillation (AF). Very late AF recurrence (≥12 months post-ablation) is uncommon and may represent a unique patient cohort.
Methods and Results: A nested case-control study was performed in the cohort who underwent AF ablation at the University of Pennsylvania to characterize patients who develop very late AF recurrence after ablation. The procedure consisted of isolation of pulmonary veins (PVs) demonstrating triggers and elimination of non-PV triggers initiating AF. Twenty-seven (7.9%) patients with very late recurrence were compared to 219 patients without recurrence and ≥12 months of follow-up. The mean age was 54.6 ± 11.3 years and 79% were men. Very late recurrence patients more likely weighed >200 lbs (70% vs 55%, P = 0.01); during initial ablation had fewer PVs isolated (2.8 ± 1.1 vs 3.3 ± 1.0, P = 0.03); and were less likely to have right inferior PV isolation (37% vs 61%, P = 0.02), less likely to have isolation of all PVs (30% vs 56%, P = 0.01), and more likely to have non-PV triggers (30% vs 11% OR 3.4(95% CI, 1.3–8.7), P = 0.01). PV reconnectivity and new triggers were found in the majority of patients with very late recurrence of AF who underwent repeat ablation.
Conclusion: Very late recurrence of AF more likely occurred in patients >200 lbs who demonstrated non-PV triggers and did not undergo right inferior PV isolation. The majority of patients undergoing repeat ablation for very late recurrence demonstrated PV reconnectivity and new non-PV and PV triggers not observed during the initial ablation.     

Role of Right Middle Pulmonary Vein in Patients with Paroxysmal Atrial Fibrillation

INTRODUCTION: Elimination of the ectopic foci from pulmonary veins (PVs) has proved to be a curative therapy for focal atrial fibrillation (AF). However, information about the importance of the right middle PV (RMPV) in initiation of AF and radiofrequency ablation of AF is limited. METHOD AND RESULTS: Forty-three patients (34 men and 9 women; age 65+/-12 years) with drug-refractory paroxysmal AF underwent electrophysiologic study and catheter ablation for treatment of AF. Three-dimensional magnetic resonance angiography (MRA) of the PVs and left atrium (LA) was performed to determine the anatomic patterns of RMPV. Diameter of PV ostium was measured at the junction of the LA and each PV. MRA findings showed the following: (1) 36 (84%) of 43 patients had a discrete RMPV; (2) there are three drainage patterns of RMPV, including joining the proximal part (<1 cm from the ostium) of the right superior PV (RSPV), joining the right inferior PV (RIPV), and a separate RMPV ostium in the LA wall; and (3) the ostial diameter of RMPV was significantly smaller than RSPV and RIPV (P < 0.01). Electrophysiologic studies demonstrated that five AF foci arose from RMPV. The coupling interval between the ectopic beat of AF and sinus beat was longer in RMPV than RSPV (262+/-45 msec vs 212+/-47 msec; P = 0.043). All AFs from RMPV were ablated successfully. PV stenosis or AF recurrence from RMPV was not found during follow-up of 10+/-4 months. CONCLUSION: RMPV was detected by MRA in >80% of paroxysmal AF patients. Ectopy from RMPV can initiate AF, and radiofrequency ablation of RMPV foci is feasible and safe.     

Predictors of Early and Late Recurrence of Atrial Fibrillation after Catheter Ablation of Paroxysmal Atrial Fibrillation

INTRODUCTION: The outcome of patients with early recurrence of atrial fibrillation (AF) (within one month) after ablation procedure is controversial. Furthermore, the predictors of early and late (up to mean follow-up 30 months) recurrence of AF are not investigated in depth. AIMS OF THE STUDY: The aim of the present study was to investigate the predictors of early and late recurrence of AF after catheter ablation of arrhythmogenic foci initiating AF in patients with paroxysmal AF. METHODS AND RESULTS: The study included 207 patients (155 men; mean age 62 +/- 13 years) who received catheter ablation of paroxysmal AF. Eighty-one (39%) patients had early recurrence of AF. Five clinical variables were related to the early recurrence of AF: (1) old age (>/=65 years) ( P = 0.004); (2) presence of associated cardiovascular disease ( P = 0.01); (3) presence of multiple AF foci ( P = 0.004); (4) presence of AF foci from left atrial free wall ( P = 0.039); (5) left atrial enlargement ( P = 0.038). Multivariate analysis demonstrated that presence of multiple AF foci could predict early recurrence of AF ( P = 0.013; ratio = 2.24; 95% CI 1.18 to 4.25). During the follow-up period (30 +/- 11 months), 70 (34%) patients had late recurrence of AF, and two clinical variables were related to the late recurrence of AF: (1) presence of early recurrence of AF ( P = 0.025); (2) presence of multiple AF foci ( P = 0.034). Multivariate analysis found that presence of early recurrence of AF could predict late recurrence of AF ( P = 0.046; hazard ratio = 1.62; 95% CI 1.01 to 2.59). Late recurrence of AF happened in 35 (43%) of the 81 patients with early recurrence of AF, and in 35 (28%) of the 126 patients without early recurrence of AF. CONCLUSIONS: Early AF recurrence could predict late AF recurrence.     

Predicting the arrhythmogenic foci of atrial fibrillation before atrial transseptal procedure: implication for catheter ablation

INTRODUCTION: Use of endocardial atrial activation sequences from recording catheters in the right atrium, His bundle, and coronary sinus to predict the location of initiating foci of atrial fibrillation (AF) before an atrial transseptal procedure has not been reported. The purpose of the present study was to develop an algorithm using endocardial atrial activation sequences to predict the location of initiating foci of AF before transseptal procedure. METHODS AND RESULTS: Seventy-five patients (60 men and 15 women, age 68 +/- 12 years) with frequent episodes of paroxysmal AF were referred for radiofrequency ablation. By retrospective analysis, characteristics of the endocardial atrial activation sequences of right atrial, His-bundle, and coronary sinus catheters from the initial 37 patients were correlated with the location of initiating foci of AF, which were confirmed by successful ablation. The endocardial atrial activation sequences of the other 38 patients were evaluated prospectively to predict the location of initiating foci of AF before transseptal procedure using the algorithm derived from the retrospective analysis. Accuracy of the value <0 msec (obtained by subtracting the time interval between high right atrium and His-bundle atrial activation during atrial premature beats from that obtained during sinus rhythm) for discriminating the superior vena cava or upper portion of the crista terminalis from the pulmonary vein (PV) foci was 100%. When the interval between atrial activation of ostial and distal pairs of the coronary sinus catheter of the atrial premature beats was <0 msec, the accuracy for discriminating left PV foci from right PV foci was 92% in the 24 foci from the left PVs and 100% in the 19 foci from the right PVs. CONCLUSION: Endocardial atrial activation sequences from right atrial, His-bundle, and coronary sinus catheters can accurately predict the location of initiating foci of AF before transseptal procedure. This may facilitate mapping and radiofrequency ablation of paroxysmal AF.     

心房颤动导管消融复发患者二次消融研究

目的心房颤动（房颤）导管消融治疗仍然存在一定的复发率,而其复发的特点目前仍然不清,本文对房颤消融复发患者二次消融的特点进行分析。方法共442例房颤消融治疗患者中,29例消融后复发的患者[男性19例,年龄（56±11）岁],本文患者复发时间〉6个月。对这些复发患者进行二次导管消融治疗。分析和对比初次与二次消融的电生理特点。结果29例房颤患者（20例为阵发性房颤,9例为持续性房颤）复发时间6—33（11．3±5．3）个月,所有患者初次消融后均服用3个月抗心律失常药。在复发的29例患者中,（1）3例初次消融术采用单纯靶肺静脉电隔离,二次消融发现1例出现非消融肺静脉触发灶,予以补充消融;另2例发现原靶肺静脉均有传导恢复,予以所有肺静脉经验性电隔离。（2）12例初次消融策略为所有肺静脉（48根）经验性电隔离,二次消融时发现所有患者存在不同程度的肺静脉传导恢复（36根）,8例再次所有肺静脉节段电隔离（其中1例发现上腔静脉起源予以针对性电隔离）;4例患者采用三维标测系统指导下同侧肺静脉环形电隔离。（3）12例患者初次消融策略为三维标测系统指导下同侧肺静脉环形电隔离,二次消融时重复进行环肺静脉电隔离。1例患者术中发现左心房局灶性房性心动过速（房速）并成功消融,2例患者术中出现左心房不典型心房扑动（房扑）成功消融。二次消融术后随访（15±10）个月,5例患者出现房颤复发（阵发性房颤1例,持续性房颤4例;成功率82．8％）,1例患者出现严重左肺静脉狭窄。结论对于房颤进行肺静脉消融电隔离治疗,其复发患者以肺静脉传导恢复为复发的主要原因。单纯进行靶肺静脉消融的部分患者,其他肺静脉的触发灶对于复发起着重要的作用。部分复发患者与非肺静脉起源的触发灶相关。复发的房颤患者,再次导管消融治疗可以达到较高的治疗成功率。     

Characteristics and outcome in patients receiving multiple (more than two) catheter ablation procedures for paroxysmal atrial fibrillation

Background: The features of multiple catheter ablation procedures for paroxysmal atrial fibrillation (AF) are unknown. We aimed to investigate the electrophysiologic characteristics and the clinical outcomes in the patients with AF who received more than two ablation procedures.
Methods: The study consisted of 15 consecutive patients (age 48 ± 14 years, 10 males) who had undergone three to five (3.3 ± 0.6) catheter ablation procedures for recurrent paroxysmal AF.
Results: Ten patients had pulmonary vein (PV)-AF and one had AF originating from both PVs and the superior vena cava (SVC) in the first ablation procedure. All of them exhibited PV reconnection during the recurrent episodes. Four of the 15 patients had AF originating from non-PV foci (three from the SVC, one from the crista terminalis) in the first procedure, and two had AF recurrences due to recovered conduction from the SVC. In all patients with PV-AF recurrences, repeated PV isolation procedures could effectively eliminate the AF. The incidence of the need for additional LA linear ablation lesions was higher comparing between the first procedure and in the following ablation procedures (18% vs. 71%, P = 0.02). During a follow-up of 1.7 ± 1.1 years, 73% of the patients remained in sinus rhythm without any antiarrhythmic drugs after the final procedure.
Conclusions: Recovered PV connection was the major cause of the AF recurrences despite undergoing multiple catheter ablation procedures. It is advisable to inspect all PVs during the AF recurrence. Repeated PV isolation plus left atrial linear ablations could effectively eliminate the AF with satisfactory outcomes.     

心房颤动射频消融术后晚期复发的相关因素

目的:分析心房颤动（房颤）经导管射频消融术后晚期复发的相关因素。方法:房颤患者117例接受经导管射频消融术治疗,术前进行常规检查评估,在CARTO三维标测系统指导下行左房环肺静脉消融,必要时加行左房线性消融、右房线性消融等策略。如果在消融结束后心电监护仍为房颤心律,则行体外电复律。通过术后随访（>3个月）确定房颤消融术后是否复发,收集相关的随访资料分析房颤术后晚期复发的预测因素。结果:①所有患者均完成环肺静脉隔离。58例患者在环肺静脉消融基础上加行左房线性消融、右房线性消融等方法。37例房颤患者在消融后房颤仍持续,经体外电转复均恢复窦律。32例(27.3%)患者在术后晚期复发。②单因素分析显示性别、并发器质性心脏病、房颤病程、持续性房颤、左房内径、左室射血分数和复律与术后房颤晚期复发相关（均P<0.05）。③经多因素分析后仅有性别、左房内径、房颤病程是房颤晚期复发的独立预测指标(分别P<0.05,P<0.05,P<0.01)。结论:性别、房颤病程、左房内径是房颤导管消融术后晚期复发的独立预测因素。     

Prevalence, electrophysiological properties, and clinical implications of dissociated pulmonary vein activity following pulmonary vein antrum isolation

The objective of this study was to investigate the prevalence, electrophysiologic properties, and clinical implications of dissociated pulmonary vein (PV) activity after PV antrum isolation (PVAI) in patients with paroxysmal atrial fibrillation (AF). One hundred seventy-three consecutive patients (61 ±10 years old, 141 men) with drug-refractory paroxysmal AF who underwent AF ablation were analyzed. After identification of arrhythmogenic foci, PVAI was performed in all patients. Of the total 346 isolated ipsilateral PVs, 97 (28.0%) were silent, 35 (10.1%) demonstrated isolated ectopic beats, 209 (60.4%) demonstrated a regular ectopic rhythm, and 5 (1.4%) demonstrated fibrillatory activity. The culprit thoracic vein was identified in 77 patients (44.5%). After isolation of ipsilateral PVs, venous activity was observed in 68 (79.1%) and 178 (68.5%) PVs among the 86 PVs with AF triggers and 260 PVs without AF triggers, respectively (p = 0.06). There was no significant difference in the incidence of acute PV reconnections exposed by adenosine triphosphate between the 97 silent ipsilateral PVs and 209 ipsilateral PVs with dissociated PV activity after the PVAI (20.6% vs 19.1%, p = 0.78). After a mean follow-up of 48.7 ± 7.9 months there was no significant difference in rates of freedom from atrial tachyarrhythmias after a single procedure between patients with and those without dissociated activity (62.1% vs 63.3%, p = 0.74, log-rank test). In conclusion, although dissociated PV activity appearing after PV isolation is an important electrophysiologic finding to prove bidirectional conduction block between the left atrium and the PV during the procedure, the clinical implications might be limited.     

Effect of pulmonary vein isolation on the left-to-right atrial dominant frequency gradient in human atrial fibrillation

BACKGROUND: We previously demonstrated the existence of a left-to-right atrial dominant frequency gradient during paroxysmal but not persistent atrial fibrillation (AF) in humans. One possible mechanism of the left-to-right dominant frequency gradient involves the role of the pulmonary veins (PVs) in AF maintenance. OBJECTIVES: The purpose of this study was to examine the effect of PV isolation on the dominant frequency gradient and outcome after PV isolation. METHODS: Patients with either paroxysmal or persistent AF were studied. Recordings were made from catheters in the coronary sinus (CS), posterior right atrium (RA), and posterior left atrium (LA) during AF before and after PV isolation. Mean left-to-right dominant frequency gradient was measured before and after segmental PV isolation. Patients were followed for AF recurrence after PV isolation. RESULTS: Twenty-seven patients with paroxysmal (n = 15) or persistent (n = 12) AF were studied. In the paroxysmal group, baseline dominant frequency was greatest in the posterior LA with a significant left-to-right atrial dominant frequency gradient (posterior LA = 6.2 +/- 0.9 Hz, CS = 5.8 +/- 0.8 Hz, posterior RA = 5.4 +/- 0.9 Hz; P <.001). After PV isolation, there was no regional difference in dominant frequency (5.9 +/- 0.7 Hz vs 5.7 +/- 0.6 Hz vs 5.7 +/- 0.7 Hz, respectively; P = NS). In the persistent AF group, there was no overall difference in dominant frequency among sites before or after PV isolation (P = NS); however, patients with long-term freedom from AF after PV isolation had a higher left-to-right dominant frequency gradient compared with patients with recurrent AF (0.4 vs 0.1 Hz; P <.05). CONCLUSION: PV isolation results in a loss in the left-to-right dominant frequency gradient in patients with paroxysmal AF. This finding supports the critical role of PVs in the maintenance of ongoing paroxysmal AF. Patients with persistent AF and a baseline left-to-right dominant frequency gradient have a better success rate with PV isolation alone compared with patients without a dominant frequency gradient.     

阵发性心房颤动患者心房及肺静脉不应期离散度的变化

目的探讨阵发性房颤患者房颤相关组织的电生理特性改变情况。方法选取阵发性房颤患者10例(房颤组)和无房颤病史的左侧旁路有显性预激波患者15例(对照组)。将大头电极分别放置在两组患者左上肺静脉、左下肺静脉、右上肺静脉、右下肺静脉开口及左心房顶壁、前壁、后壁、高位右心房,分别测定各部位有效不应期(EPR)。结果①房颤组心房及肺静脉EPR离散度指数(DI)为0.117±0.028,对照组为0.074±0.029,两组比较,P<0.05。②房颤组左心房ERP为(234.00±28.72)ms,肺静脉ERP为(230.75±32.69)ms;对照组左心房ERP为(248.00±25.99)ms,肺静脉ERP为(244.33±26.78)ms,两组比较,P均<0.05。结论阵发性房颤患者DI明显增大,左心房、肺静脉ERP显著缩短。     

Ablation of Focally Induced Atrial Fibrillation:

INTRODUCTION: Focally induced atrial fibrillation (AF) often is due to ectopic activity in the pulmonary veins (PV). Although initial approaches were aimed at ablating only the ectopic foci, more extensive ablation approaches have evolved that isolate all PVs empirically and/or create circumferential ablation lines in the left atrium (LA). These techniques last longer and may be associated with more risks. We retrospectively evaluated the outcome and risks of ablation for focally induced AF in a single-center patient population. METHODS AND RESULTS: We report on 47 patients (32 men and 15 women; age 47 +/- 10 years) in whom 52 ablations were performed. In 19 patients (22 sessions), ablation was directed at the site(s) of overt ectopic activity ("selective" group), whereas in 28 patients (30 sessions) without sufficient ectopy to determine the culprit PV a mean of 3.5 PVs were empirically targeted for bidirectional disconnection from the LA ("extensive" group). On a preprocedural Holter recording, the "selective" group had significantly more isolated atrial ectopy (3,276 +/- 2,933 vs 620 +/- 937 beats/24 hours) and runs of atrial tachycardia (330 +/- 202 vs 53 +/- 87 runs/24 hours) than the "extensive" group (P < 0.01 for both). Only 11% had persistent AF before ablation. Acute procedural success was 81% (elimination of all ectopy) and 83%, respectively (bidirectional and fully circumferential isolation of all targeted PVs). Procedure and fluoroscopy times were significantly shorter in the "selective" group. There were no major complications, but 7 minor complications and 2 acute PV stenoses > 50% in the 30 "extensive" procedures were observed. Mean follow-up was 8.4 +/- 8.5 months (median 6.9). Kaplan-Meier analysis, excluding recurrences during only the first month ("delayed cure"), showed AF recurrence in 45% after 6 months and in 55% after 1 year. Outcome was not dependent on ablation approach ("selective" or "extensive") nor was time to first AF (22 +/- 64 days and 30 +/- 69 days). AF recurrence tended to be higher in patients with larger LA (P = 0.08), underlying heart disease or hypertension (P = 0.08), and those "extensive" patients in whom not all 4 PVs were targeted (P = 0.07). CONCLUSION: Trigger-directed ablation for focally induced AF is associated with a relatively high recurrence rate during follow-up. Apart from recurrence of the ectopic trigger, this may point to underlying structural changes in the atrial substrate not addressed by the ablation. Prospective evaluation of the risk-to-benefit profile of any technique (selective, extensive, including linear lines) is required.     

New technique for simultaneous catheter mapping of pulmonary veins for catheter ablation in focal atrial fibrillation

INTRODUCTION: Most focal atrial fibrillation (AF) can be triggered by premature beats from pulmonary veins (PVs), and ablation of these foci could cure AF. However, it is difficult to locate the trigger points of PVs using only one mapping catheter. The purpose of the present study was to investigate the efficacy of using four mapping catheters in four PVs simultaneously in the ablation of focal AF. METHODS AND RESULTS: Thirty-two patients with frequent attacks of paroxysmal AF triggered by PV foci were included. After a transseptal procedure, three 2-french microcatheters and one 7-french catheter for ablation were placed into each of the PVs, and mapping of the four PVs was performed simultaneously. Fifty-eight foci were identified; 51 triggers (88%) originated from the PV and 7 (12%) from atrial tissue. The trigger points of AF were found in a single focus in 14 patients, in 2 foci in 12 patients, and in 3-4 foci in 6 patients. During a mean follow-up period of 10 +/- 4 months, ablation eliminated AF without drugs in 86, 50 and 33% of the patients with 1, 2 and 3-4 targeted PVs, respectively; 20 patients (63%) were successfully ablated. Age, history of AF, the dimension of the left atrium and the number of focal origins were significant predictors of success. CONCLUSION: The technique of simultaneous mapping of PVs using quadruple catheters is a feasible and effective method for mapping the trigger points and ablation of focal AF originating from PVs.     

心房颤动肺静脉电隔离后肺静脉自发电位分析

目的探讨心房颤动(简称房颤)患者肺静脉电隔离后发生肺静脉自发电位的相关因素。方法153例患者,其中阵发性房颤114例,持续性或永久性房颤39例,术前行肺静脉CT血管造影并测量肺静脉最大直径,行环肺静脉消融肺静脉电隔离术,并进行肺静脉自发电位标测及其相关因素评价。结果术中,69例(45.1%)共125根肺静脉(20.1%,125/621)标测到自发电位。左上肺静脉最大径(LSPV,18.5±4.0mm)及右上肺静脉最大径(RSPV,18.7±4.2mm)均大于左下肺静脉(LIPV,15.2±3.0mm)及右下肺静脉(RIPV,16.3±3.8mm)(P均<0.001),右侧肺静脉大于左侧肺静脉(17.5±4.2mmvs16.8±3.9mm,P=0.012);有自发电位的RSPV最大径大于无自发电位的RSPV(20.0±3.8mmvs18.3±4.3mm,P=0.027)。右侧肺静脉自发电位发生率高于左侧肺静脉(25.5%vs15.1%,P=0.002),RSPV和RIPV自发电位发生率均高于LIPV(27.2%,23.8%vs11.4%,P<0.001与P=0.005)。RSPV自发电位发生率与RSPV最大径正相关(β=0.097,P<0.05)。结论肺静脉最大径越大则自发电位的发生率越高,而RSPV有无自发电位与RSPV最大径明显相关。     

Cryoballoon Versus Radiofrequency for Pulmonary Vein Re‐Isolation After a Failed Initial Ablation Procedure in Patients with Paroxysmal Atrial Fibrillation

Cryoballoon versus Radiofrequency Ablation . Aim: Catheter ablation of paroxysmal atrial fibrillation (PAF) is associated with an important risk of early and late recurrence, necessitating repeat ablation procedures. The aim of this prospective randomized patient‐blind study was to compare the efficacy and safety of cryoballoon (Cryo) versus radiofrequency (RF) ablation of PAF after failed initial RF ablation procedure. Methods: Patients with a history of symptomatic PAF after a previous failed first RF ablation procedure were eligible for this study. Patients were randomized to Cryo or RF redo ablation. The primary endpoint of the study was recurrence of atrial tachyarrhythmia, including AF and left atrial flutter/tachycardia, after a second ablation procedure at 1 year of follow‐up. All patients were implanted with a cardiac monitor (Reveal XT, Medtronic) to continuously track the cardiac rhythm. Patients with an AF burden (AF%) ≤ 0.5% were considered AF‐free (Responders), while those with an AF% > 0.5% were classified as patients with AF recurrences (non‐Responders). Results: Eighty patients with AF recurrences after a first RF pulmonary vein isolation (PVI) were randomized to Cryo (N = 40) or to RF (N = 40). Electrical potentials were recorded in 77 mapped PVs (1.9 ± 0.8 per patient) in Cryo Group and 72 PVs (1.7 ± 0.8 per patient) in RF Group (P = 0.62), all of which were targeted. In Cryo group, 68 (88%) of the 77 PVs were re‐isolated using only Cryo technique; the remaining 9 PVs were re‐isolated using RF. In RF group, all 72 PVs were successfully re‐isolated (P = 0.003 vs Cryo). By intention‐to‐treat, 23 (58%) RF patients were AF‐free vs 17 (43%) Cryo patients on no antiarrhythmic drugs at 1 year (P = 0.06). Three patients had temporary phrenic nerve paralysis in the Cryo group; the RF group had no complications. Of the 29 patients who had only Cryo PVI without any RF ablation, 11 (38%) were AF‐free vs 20 (59%) of the 34 patients who had RF only (P = 0.021). Conclusion: When patients require a redo pulmonary vein isolation ablation procedure for recurrent PAF, RF appears to be the preferred energy source relative to Cryo. (J Cardiovasc Electrophysiol, Vol. 24, pp. 274‐279, March 2013)     

Ablation of superior pulmonary veins compared to ablation of all four pulmonary veins:

INTRODUCTION: Isolation of all pulmonary veins (PV) is advocated for treatment of paroxysmal atrial fibrillation (PAF). However, the superior PVs are responsible for most AF triggers, whereas the inferior PVs carry the higher risk for ablation-induced ostial stenosis. The aim of this study was to compare a superior PV isolation approach with isolation of all PVs for treatment of PAF. METHODS AND RESULTS: Fifty-two patients with PAF were randomized to either left superior pulmonary vein (LSPV) isolation followed by additional isolation of the right superior pulmonary vein (RSPV) in case of AF recurrence (group A, n = 27) or isolation of all four PVs followed by a repeat procedure in case of recurrence (group B, n = 25). At 1-year follow-up, 11 patients (41%) in group A and 8 patients (32%) in group B had AF relapse (P = 0.55). No significant differences in AF relapse were detected between groups at 3 and 12 months (log rank = 0.36, P = 0.54) and by Cox proportional hazards model analysis (P = 0.62). Nonsignificant PV stenosis was detected in two patients from group B. Total radiofrequency energy delivery and fluoroscopy and procedure times were lower in group A: 8.9 +/- 1.4 minutes vs 25.6 +/- 3.7 minutes (P < 0.001), 22.2 +/- 6.8 minutes vs 62 +/- 10.3 minutes (P < 0.001), and 131.8 +/- 26.5 minutes vs 222.2 +/- 32.3 minutes (P < 0.001), respectively. CONCLUSION: A staged superior PVs isolation approach confers equal success rates but with reduced radiofrequency energy delivery and fluoroscopy and procedure times compared to isolation of all PVs at the initial ablation attempt.     

Electroanatomic characteristics of atrial premature beats triggering atrial fibrillation in patients with persistent versus paroxysmal atrial fibrillation

APBs in Persistent Versus Paroxysmal AF. BACKGROUND: Although the electrical disconnection between the left atrium (LA) and pulmonary veins (PVs) by radiofrequency catheter ablation has been proven to be effective in controlling atrial fibrillation (AF), the recurrence rate is higher in patients with persistent AF (PeAF) than with paroxysmal AF (PAF). We hypothesized that the origin of the atrial premature beats (APBs) that trigger AF and the pattern of their breakthrough into the LA differ between PAF and PeAF. METHODS: We mapped 75 APBs (53 APBs triggering AF, 22 isolated APBs) from the LA and PVs in 26 patients with AF (age: 49.5 +/- 9.6, males: 23, PAF = 17, PeAF = 9), using a noncontact endocardial mapping (NCM) system. The location of the preferential conduction (PC) sites and their conduction velocity (CV) were compared. RESULTS: In patients with PeAF, the earliest activation (EA) site and exit of the PC were more frequently located on the LA side of the LA-PV junction as compared with PAF (P < 0.001). Eighty-one percent of the PCs were located in the area between the left and right superior PVs. The incidence of PCs was similar between the PeAF and PAF patients (P = NS). PCs were more commonly found with APBs inducing AF (63.3%) than with those not inducing AF (35.2%, P = 0.01). The CV of the PC was slower for PeAF than PAF (P < 0.001). The CV in the LA during sinus rhythm was also slower for PeAF than PAF (P < 0.01). CONCLUSION: PeAF was more frequently triggered by APBs from the LA side of the LA-PV junction than PAF and resulted in slower conduction than did PAF. These findings may help explain the higher potential for recurrence after electrical PV isolation in patients with PeAF.     

典型心房扑动对心房颤动导管消融复发的影响

目的 评价典型心房扑动(房扑)对心房颤动(房颤)导管消融复发的影响.方法 120例药物治疗无效的阵发性房颤患者在三维电解剖标测系统和肺静脉环状标测电极导管联合指导下行环肺静脉电隔离.其中17例(14.2%)合并典型房扑(房扑组,其余作为对照组),行三尖瓣环峡部消融,三尖瓣环峡部消融终点为三尖瓣环峡部双向阻滞.房颤复发定义为导管消融3个月后发生房性快速心律失常.结果 房扑组房颤病程(9.8±10.7)年,长于对照组(5.9±6.3)年,差异有统计学意义(P=0.036).房扑组与对照组相比,年龄、性别、合并器质性心脏病、左心房直径、左心室射血分数差异无统计学意义.随访91～401(237±79)d,房扑组房颤复发率为47.1%,对照组房颤复发率为12.6%,两组间差异有统计学意义(P=0.001).经校正年龄、房颤病程、合并器质性心脏病、左心房直径等因素,Cox多因素分析发现消融术前合并房扑是房颤复发的独立危险因素(危险比3.52,95%可信区间1.32～9.34,P=0.012).结论 典型房扑可能增加房颤导管消融术后房颤的复发,房颤导管消融前应对患者是否合并典型房扑进行认真评价.