Recurrence of left atrium-pulmonary vein conduction following successful disconnection in asymptomatic patients.

BACKGROUND: The clinical significance of conduction recurrences in isolated pulmonary veins of patients with atrial fibrillation is not established. METHODS: Twenty-two patients with paoxysmal atrial fibrillation underwent successful pulmonary vein isolation. Six months after the procedure, 14 patients were free of atrial fibrillation. Two of these patients were subjected to repeat mapping of the left superior pulmonary vein. RESULTS: There was recurrence of pulmonary vein to left atrium conduction despite complete lack of symptoms or evidence of recurrent atrial fibrillation. CONCLUSION: Successful pulmonary vein isolation with abolition of paroxysmal atrial fibrillation does not confer permanent disconnection of the pulmonary vein musculature from the left atrium.     

Left atrial flutter after radiofrequency catheter ablation of focal atrial fibrillation

We report an arrhythmic complication in two patients in whom a procedure directed at isolating one or two pulmonary veins had been performed. The complication was related to pulmonary vein disconnection scars after ablation. Both patients developed new clinical tachycardia (atypical atrial flutter) secondary to a reentrant phenomena in the vicinity of a previously ablated pulmonary vein.     

The Adjunctive Role of Nonpulmonary Venous Ablation in the Cure of Atrial Fibrillation

Atrial fibrillation is highly prevalent and accounts for significant morbidity, mortality, and health care costs. Catheter ablation has become a therapeutic option in the management of this challenging arrhythmia. To optimize procedure safety and long-term efficacy, different ablation strategies have been evaluated, targeting either the triggers initiating atrial fibrillation or the substrate responsible for its maintenance. This report summarizes some of the innovative contributions on the adjunctive role of nonpulmonary venous ablation approaches in the cure of atrial fibrillation.     

心房颤动冷冻消融方法的应用进展

肺静脉隔离是心房颤动（房颤）导管消融的基石,冷冻球囊是专门为肺静脉解剖结构设计的工具,应用冷冻球囊 导管进行肺静脉隔离（PVI）的有效性和安全性获得了临床研究证实,国内外指南都已将冷冻球囊消融作为房颤消融 PVI的标准疗法。冷冻球囊消融具有持久肺静脉隔离、安全性高、操作简便、患者感受好、学习曲线短等优势,因此, 近10年在临床得以迅速普及应用。随着技术的不断创新和临床研究的深入,冷冻球囊消融疗法也在不断拓展。文 章就房颤冷冻球囊消融方法及应用进展进行论述。     

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.     

Identifying the relationship between the non-PV triggers and the critical CFAE sites post-PVAI to curtail the extent of atrial ablation in longstanding persistent AF

Relationship Between the Non‐PV Triggers and the Critical CFAE Sites. Background: Complex fractionated atrial electrograms (CFAE) ablation has been performed in addition to pulmonary veins (PV) isolation to increase the success rate of atrial fibrillation (AF) ablation in patients with longstanding (LS) persistent AF. The mechanism underlying the clinical benefit of CFAE ablation remains, however, poorly understood. Objective: We compared the impact of CFAE ablation on the prevalence of non‐PV atrial triggers inducing AF in 2 groups of patients with LS persistent AF. One group underwent PVAI alone, and the other group underwent PVAI plus CFAE ablation. In addition, we correlated the site of non‐PV triggers with the presence of CFAE. Methods: A total of 98 consecutive patients with symptomatic drug refractory LS persistent AF presenting for ablation had a preablation electroanatomic CFAE map. Patients randomized to either isolation of the PVs and posterior wall (PVAI) (group I, n = 48 pts) or PVAI and biatrial ablation of CFAEs (group II, 50 pts). After ablation, infusion of isoproterenol up to 30 mcg/min was given to reveal non PV foci inducing AF. Those foci were mapped and correlated with CFAE regions and ablated. Results: A total of 19 patients (76%) with PV foci inducing AF were associated with either stable or transient CFAE after PVAI, respectively, in 12 patients (48%) and 7 patients (28%). A total of 20 (42%) non‐PV triggers were observed in group I versus 5 (10%) in group II (P < 0.001) in 18 and 5 patients, respectively. After a mean f/u of 17.2 ± 5.2 months, 33 (69%) patients in group I and 36 (72%) patients in group II were in SR (P = NS). Conclusion: Non‐PV triggers inducing AF post‐PVAI were associated with the presence of stable or transient CFAE in 48% and 28% of cases, respectively, in LS persistent AF. CFAE ablation after PVAI was associated with a significantly higher elimination of those non‐PV triggers. This suggests that at least part of the beneficial effect achieved by CFAE ablation reflects elimination of non‐PV AF triggers. (J Cardiovasc Electrophysiol, Vol. pp. 1‐7)     

Curative Ablation for Atrial Fibrillation:

In contrast to other supraventricular tachycardias, curative treatment of atrial fibrillation, although increasingly available and rapidly evolving, is neither as effective nor the first choice. Until recently, the unavailability of nonsurgical curative treatment may have fueled a debate on the relative importance of restoring sinus rhythm versus controlling the ventricular rate during atrial fibrillation. Recent randomized trials (PIAF, AFFIRM, and RACE) using very limited atrial fibrillation burden assessment show that pharmacologic ventricular rate control is much safer and possibly more effective than pharmacologic restoration of sinus rhythm. A clinical trial comparing a truly curative treatment of atrial fibrillation—such as catheter ablation targeting pulmonary vein isolation—with pharmacologic treatment is required. It should focus on reliable efficacy parameters, use vigilant assessment of safety, and, most importantly, be structured to provide all-important prognostic information on long-term outcome. Atrial fibrillation burden is a theoretically robust efficacy parameter, but accurate quantification over a sufficiently long period of monitoring will require technologically innovative noninvasive rhythm monitoring devices. (J Cardiovasc Electrophysiol, Vol. 14, pp. S48-S51, September 2003, Suppl.)     

Carto指引下环肺静脉导管消融术的达终点靶点分析及临床评价

目的:探讨环肺静脉导管消融术(CPVI)达终点部位及其分布规律,更有效地指导其达到肺静脉电隔离。方法:96例药物治疗无效的有临床症状的心房颤动患者。通过Carto电解剖标测系统三维标测指引下行CPVI。消融终点为完成环状消融线并实现肺静脉电位消失即肺静脉电隔离。结果:96例患者CPVI时记录到的消融靶点达终点部位203处,包括左侧肺静脉114处,位于左前上(45处,39.5%),左前下(26处,22.8%)和左前中(16处,14.0%);环右侧肺静脉89处,分别位于右后上(40处,44.9%)和右中下(27处,30.3%)。9例再次行CPVI的电隔离者与上述部位一致。手术并发症包括:1例少量心包积液,1例顽固性呃逆,血气胸1例,迷走反射2例,2例颈部血肿。结论:CPVI达终点部位有一定规律,多见于左侧肺静脉消融线前壁和右侧肺静脉消融线后壁,可为再次消融有效提示消融达终点部位的大体位置。     

心房颤动肺静脉电隔离术后早期复发的临床意义

目的:总结分析心房颤动(房颤)肺静脉电隔离术后早期(2周内)房颤复发者的随访结果.方法:105例房颤患者[平均年龄(55±12)岁],采用导管进行环肺静脉电隔离治疗,其中阵发性房颤78例,持续性房颤27例.实施环肺静脉电隔离共358根.结果:在术后早期随访[平均(3.9±2.6)d]中,105例患者中38例(36%)复发房颤.阵发性房颤与持续性房颤者早期房颤复发的发生率相比,差异无统计学意义(35%∶41%,P>0.05).在后期随访[平均(208±125)d]中,67例早期未复发患者中58例(87%)、38例早期房颤复发患者中13例(34%)无房颤发生,二者成功率比较,P<0.01.结论:肺静脉电隔离术后2周内大约36%患者房颤复发,早期房颤复发患者较早期未复发者后期成功率低.     

Incidence of atrial fibrillation in heart transplant patients: long-term follow-up

BACKGROUND: The incidence of atrial fibrillation (AF) in heart transplant patients has not been well documented. METHODS: To determine the incidence of AF in a cohort of patients undergoing cardiac transplantation, clinical data were obtained from a prospectively collected database for all consecutive orthotopic heart transplantation (OHT) patients and for all consecutive coronary artery bypass graft (CABG) surgery patients between January 1984 and March 2004 at our institution. A cohort of 1,714 OHT patients and low-risk CABG (normal ejection fraction [EF] and no left ventricular hypertrophy [LVH]) patients were age- and sex-matched. RESULTS: The average age in the two groups was 56 +/- 7 years with 87% male and 81% white race and body mass index (BMI) of 26 +/- 4. There were 3 cases of AF (0.3%) in the OHT group and 757 cases of AF (21%) in the low-risk CABG group. The strongest independent predictor of freedom from postoperative AF was having had a transplant (odds ratio [OR] 96, 95% confidence interval [CI] 13-720). The incidence of AF, atrial flutter (AFL), and supraventricular tachycardia (SVT) in OHT was 0.33, 2.8%, and 1.3%, respectively. Given that incidence of AF, AFL, and SVT in historical post-CABG population is 25%, 17%, and 4.3%, transplanted patients appear to have lower incidence of AF, AFL, and SVT than the reference population. Consistent with this, transplanted patients underwent few ablation procedures for atrial arrhythmias. Additionally, the three patients with AF had bicaval anastomoses suggesting the possibility of PACs originating in the donor superior vena cava (SVC) or IVC (inferior vena cava) initiating AF in these patients. CONCLUSIONS: In a cohort study of transplant and low-risk CABG patients, the strongest independent predictor of freedom from AF is having undergone transplant surgery. One potential explanation for the markedly lower incidence of AF may be effective isolation of thoracic veins with documented cases retaining the native SVC.     

Efficacy and safety of segmental ostial versus circumferential extra-ostial pulmonary vein isolation for atrial fibrillation

INTRODUCTION: Pulmonary vein (PV) isolation for atrial fibrillation (AF) can be performed using a segmental ostial or a circumferential extra-ostial approach. The relative merits and potential limitations of each approach are currently debated. Here we report our early experience with each of these approaches, including their relative efficacy and safety. METHODS AND RESULTS: Forty patients with drug-refractory AF underwent segmental ostial PV isolation and were compared to 40 consecutive patients who underwent PV isolation using a circumferential extra-ostial approach. The latter approach described here is novel in two aspects: (1) the endpoint for ablation was PV isolation and not only delay in left atrial to PV conduction time, and (2) isolation of the right and left PVs was achieved by a single encirclement of ipsilateral veins. At follow-up, 60% of the patients in the segmental group were free of AF compared to 75% of the patients in the circumferential group. There was one thromboembolic cerebrovascular complication during the ablation procedure in each group. CONCLUSION: PV isolation using a circumferential extra-ostial approach, where the ipsilateral PVs are isolated together by one encircling line of block using electroanatomic mapping, is a technically feasible procedure. This approach is at least as effective and safe as the more established segmental ostial approach for AF ablation.     

Additional complex fractionated atrial electrogram ablation does not improve the outcomes of non-paroxysmal atrial fibrillation: A systematic review and meta-analysis of randomized controlled trials

BackgroundNon-paroxysmal atrial fibrillation (AF) has a complex pathophysiological process. The standard catheter ablation approach is pulmonary vein isolation (PVI). The additional value of complex fractionated electrogram (CFAE) ablation is still unclear. We aimed to investigate the additional value of CFAE ablation for non-paroxysmal AF.MethodsWe performed a systematic review and meta-analysis of randomized controlled studies up to May 2020. Articles comparing pulmonary vein isolation (PVI) plus CFAE ablation and PVI alone for AF were obtained from the electronic scientific databases. The pooled mean difference (MD) and pooled risk ratio (RR) were assessed.ResultsA total of 8 randomized controlled trials (RCTs) including 1034 patients were involved. Following a single catheter ablation procedure, the presence of any atrial tachyarrhythmia (ATA) with or without the use of antiarrhythmic drugs (AADs) between both groups were not significantly different (RR = 1.1; 95% confidence interval [CI] = 0.97–1.24; p = 0.13). Similar results were also obtained for the presence of any ATA without the use of AADs (RR = 1.08; 95% CI = 0.96–1.22; p = 0.2). The additional CFAE ablation took longer procedure times (MD = 46.95 min; 95% CI = 38.27–55.63; p = < 0.01) and fluoroscopy times (MD = 11.69 min; 95% CI = 8.54–14.83; p = < 0.01).ConclusionAdditional CFAE ablation failed to improve the outcomes of non-paroxysmal AF patients. It also requires a longer duration of procedure times and fluoroscopy times.