单消融导管与单环状标测电极导管指导环肺静脉电隔离术治疗心房颤动的随机对比研究

目的 比较单消融导管指导环肺静脉电隔离术与单环状标测电极导管指导环肺静脉电隔离术治疗心房颤动（房颤）的有效性和安全性.方法 122例房颤患者随机分为单消融导管指导环肺静脉电隔离组和单环状标测电极导管指导环肺静脉电隔离组.两组患者年龄、性别、房颤发作时间、合并器质性心脏病及左心房直径、左心室射血分数、CT所测双侧肺静脉血管直径差异均无统计学意义.其中阵发性房颤86例,持续性房颤36例.结果 两组患者平均总的消融时间为（158.0±29.5）min对（158.0±28.4）min（P=0.95）,平均透视时间为（41.4±9.9）min对（37.7±9.5）min（P=0.23）.所有患者随访9个月,房颤事件的复发率为32.5%对31%.两组患者随访期间无死亡事件发生,两种消融策略均未出现心脏压塞和肺静脉狭窄,与手术相关并发症发生率为3对2例.结论 单消融导管与单环状标测电极导管指导环肺静脉电隔离术治疗房颤具有同样的安全性和有效性.     

Left atrial flutter following pulmonary vein antrum isolation with radiofrequency energy: linear lesions or repeat isolation

INTRODUCTION: Left atrial flutter (LAFL) is a known complication of pulmonary vein isolation. Treatment of this arrhythmia currently involves both linear lesions as well as re-isolation. However, it is unknown if re-isolation alone is sufficient to prevent recurrence. This study reviews the incidence of LAFL following segmental PV antrum isolation (PVAI) in a large patient population and evaluates if re-isolation alone is sufficient to prevent recurrence. METHODS AND RESULTS: Seven hundred thirty-seven patients underwent PVAI. Twenty-three patients (3.1%) developed post-PVAI LAFL. All patients underwent a second procedure in which only repeat PVAI was done. During the second procedure, all flutter circuits were electroanatomically mapped. All patients were followed at 3, 6, and 12 months. All 23 patients demonstrated recovery in one or more PV. After repeat isolation of the PVs, 61% of patients were arrhythmia free off all antiarrhythmic drugs. A relationship between the presence/absence of pre-existing left atrial (LA) scar was observed. Of the 11 patients with pre-existing LA scar, 36% remained arrhythmia free off antiarrhythmic drugs. In contrast, of the 12 patients without pre-existing LA scar, 83% remained arrhythmia free off antiarrhythmic drugs (P = 0.03). CONCLUSION: Among patients with LAFL following PVAI, re-isolation alone is sufficient in preventing recurrence in patients without pre-existing LA scar. Patients with pre-existing LA scar tend to have recurrence requiring further ablation including linear lesions, and continue to need antiarrhythmic medications.     

Usefulness of a new radiofrequency thermal balloon catheter for pulmonary vein isolation: a new device for treatment of atrial fibrillation

INTRODUCTION: A rapidly firing or triggered ectopic focus located within a pulmonary vein (PV) or close to the PV ostium could induce atrial fibrillation (AF). The aim of this study was to evaluate the efficacy and safety of a radiofrequency thermal balloon catheter for isolation of the PV from the left atrium (LA). METHODS AND RESULTS: Twenty patients with drug-resistant paroxysmal AF were treated by isolating the superior PVs using an RF thermal balloon catheter. Using a transseptal approach, the balloon, which had an inflated diameter 5 to 10 mm larger than that of the PV ostium, was wedged at the LA-PV junction. It was heated by a very-high-frequency current (13.56 MHZ) applied to the coil electrode inside the balloon for 2 to 3 minutes, and the procedure was repeated up to four times. The balloon center temperature was maintained at 60 degrees to 75 degrees C by regulating generator output. Successful PV isolation was achieved in 19 of the 20 left superior PVs and in all 20 of the right superior PVs and was associated with a decrease in amplitude of the ostial potentials. Total procedure time was 1.8 +/- 0.5 hours, which included 22 +/- 7 minutes of fluoroscopy time. After a follow-up period of 8.1 +/- 0.8 months, 17 patients were free from AF, with 10 not taking any antiarrhythmic drugs and 7 taking the same antiarrhythmic agent as before ablation. Electron beam computed tomography revealed no complications, such as PV stenosis at ablation sites. CONCLUSION: The PV and its ostial region can be safely and quickly isolated from the LA by circumferential ablation around the PV ostia using a radiofrequency thermal balloon catheter for treatment of AF.     

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.     

Acquired pulmonary vein stenosis after radiofrequency catheter ablation of paroxysmal atrial fibrillation

INTRODUCTION: Elimination of the initiating focus within the pulmonary vein (PV) using radiofrequency (RF) catheter ablation is a new treatment modality for treatment of drug-refractory atrial fibrillation. However, information on the long-term safety of RF ablation within the PV is limited. METHODS AND RESULTS: In 102 patients with drug-refractory atrial fibrillation and at least one initiating focus from the PV, series transesophageal echocardiography was performed to monitor the effect of RF ablation on the PV. There were 66 foci in the right upper PV and 65 foci in the left upper PV. Within 3 days of ablation, 26 of the ablated right upper PVs (39%) had increased peak Doppler flow velocity (mean 130+/-28 cm/sec, range 106 to 220), and 15 of the ablated left upper PVs (23%) had increased peak Doppler flow velocity (mean 140+/-39 cm/sec, range 105 to 219). Seven patients had increased peak Doppler flow velocity in both upper PVs. No factor (including age, sex, site of ablation, number of RF pulses, pulse duration, and temperature) could predict PV stenosis after RF ablation. Three patients with stenosis of both upper PVs experienced mild dyspnea on exertion, but only one had mild increase of pulmonary pressure. There was no significant change of peak and mean flow velocity and of PV diameter in sequential follow-up studies up to 16 (209+/-94 days) months. CONCLUSION: Focal PV stenosis is observed frequently after RF catheter ablation applied within the vein, but usually is without clinical significance. However, ablation within multiple PVs might cause pulmonary hypertension and should be considered a limiting factor in this procedure.     

房颤患者环肺静脉前庭射频消融路径的分析

目的比较房颤患者中3种不同环肺静脉前庭射频消融路径的消融成功率。方法回顾性分析解放军总医院心血管内科2015年6月至2017年6月住院房颤患者173例,根据射频消融线所在区域分为心房前庭组61例、肺静脉前庭组47例和前庭组65例,比较3组患者手术时间、X线曝光时间和消融时间,以及穿刺房间隔后、术后即刻和术后24 h血浆中C反应蛋白(CRP)、氨基末端B型脑钠肽前体(NT-proBNP)和白细胞介素-6(IL-6)水平。应用SPSS 17.0统计软件对数据进行分析。组间比较采用单因素方差分析、秩和检验或χ~2检验。结果所有患者在消融过程中达到完全电隔离的即刻成功率为84.39%(146/173)。心房前庭组患者消融时间明显长于肺静脉前庭组患者[(120.67±13.12)vs(90.17±6.95)min],差异有统计学意义(P0.05)。相比穿刺房间隔后,3组患者术后即刻和术后24 h IL-6水平升高,肺静脉前庭组患者术后24 h NT-proBNP水平升高;肺静脉前庭组患者术后24 h CRP水平相比心房前庭组患者[(1.99±1.09)vs(0.40±0.29)mg/L]升高,差异均具有统计学意义(P0.05)。161例随访12个月,12例失访,失访率为6.94%(12/173)。27例房颤复发,手术成功率为83.23%(134/161),其中心房前庭组手术成功率[89.83%(53/59)vs 73.33%(33/45)]高于肺静脉前庭组,差异具有统计学意义(P0.05)。结论房颤患者不同环肺静脉前庭射频消融路径中,心房前庭侧消融路径优于肺静脉前庭消融路径。     

3D mapping of phrenic nerve course for radiofrequency pulmonary vein isolation

Introduction

Phrenic nerve (PN) injury is a rare but severe complication of radiofrequency (RF) pulmonary vein isolation (PVI). The objective of this study was to characterize the typical intracardiac course of the PN with a three-dimensional electroanatomic mapping system, to quantify the need for modification of the ablation trajectory to avoid delivering an ablation lesion on sites with PN capture, and to identify very circumscribed areas of common PNC on the routine ablation trajectory of a RF-PVI, allowing fast and effective PN screening for everyday usage.

Methods

We enrolled 137 consecutive patients (63 ± 9 years, 64% men) undergoing PVI. A detailed high output (20 mA) pace-mapping protocol was performed in the right (RA) and left atrium (LA) and adjacent vasculature.

Results

The right PN was most commonly captured in the superior vena cava at a lateral (50%) or posterolateral (23%) position before descending along the RA either straight (29%) or with a posterolateral bend (20%). In the LA, beginning deep within the right superior pulmonary vein (RSPV), the right PN is most frequently detectable anterolateral (31%), then descends to the lateral proximal RSPV (23%), and further towards the lateral antral region (15%) onto the medial LA wall (12%). To avoid delivering an ablation lesion on sites with PN capture, modification of ablation trajectory was necessary in 23% of cases, most commonly in the lateral RSPV antrum (81%). No PN injury occurred.

Conclusion

PN mapping frequently reveals the close proximity of the PN to the ablation trajectory during PVI, particularly in the lateral RSPV antrum. Routine PN pacing should be considered during RF PVI procedures.     

Electrical isolation of the superior vena cava: an adjunctive strategy to pulmonary vein antrum isolation improving the outcome of AF ablation

PV isolation at the antrum (PVAI) has improved safety and efficacy of ablation procedures for atrial fibrillation (AF). AF triggers from the superior vena cava (SVC) may compromise the outcome of PVAI.
Purpose: We evaluated the (1) incidence of SVC triggers, (2) feasibility of empiric SVC electrical isolation (SVCI) as an adjunct to PVAI, and (3) SVCI safety.
Methods and Results: Of 190  patients (group I), 24 (12%) showed SVC triggers. Following PVAI, seven patients had AT originating from the SVC and three had AF. After SVCI, all 24  patients were arrhythmia-free 450 ± 180  days post procedure. In the subsequent 217  patients (group II), empirical SVCI was performed following PVAI. Sixty-six of all 407  patients (16%) experienced recurrence of AF.  A repeat procedure in 25 of the 66  patients showed that five (20%) had AF recurrence initiated by SVC triggers, of whom four were among group I patients (4/190; 2%) and one was from group II (1/217; 0.4%), (P < 0.05). Transient diaphragmatic paralysis can be avoided by pacing at the lateral aspect of the SVC using high output (30  mA). There was no SVC stenosis on CT scans before or 3 months after the procedure. There was no sinus node injury.
Conclusions: The SVC harbors the majority of non-PV triggers of AF. SVCI is feasible, safe, and may be considered as an adjunctive strategy to PVAI for ablation of AF. The long-term favorable outcome of this hybrid approach remains to be evaluated in a larger series of patients.     

Detection of inadvertent catheter movement into a pulmonary vein during radiofrequency catheter ablation by real-time impedance monitoring

Introduction: During radiofrequency ablation to encircle or isolate the pulmonary veins (PVs), applications of radiofrequency energy within a PV may result in stenosis. The aim of this study was to determine whether monitoring of real-time impedance facilitates detection of inadvertent catheter movement into a PV.
Methods and Results: In 30 consecutive patients (mean age 53 ± 11 years) who underwent a left atrial ablation procedure, the three-dimensional geometry of the left atrium, the PVs, and their ostia were reconstructed using an electroanatomic mapping system. The PV ostia were identified based on venography, changes in electrogram morphology, and manual and fluoroscopic feedback as the catheter was withdrawn from the PV into the left atrium. Real-time impedance was measured at the ostium, inside the PV at approximately 1 and 3 cm from the ostium, in the left atrial appendage, and at the posterior left atrial wall. There was an impedance gradient from the distal PV (127 ± 30 Ω) to the proximal PV (108 ± 15 Ω) to the ostium (98 ± 11 Ω) in each PV (P < 0.01). There was no significant impedance difference between the ostial and left atrial sites. During applications of radiofrequency energy, movement of the ablation catheter into a PV was accurately detected in 80% of the cases (20) when there was an abrupt increase of ≥4 Ω in real-time impedance.
Conclusion: There is a significant impedance gradient from the distal PV to the left atrium. Continuous monitoring of the real-time impedance facilitates detection of inadvertent catheter movement into a PV during applications of radiofrequency energy. (J Cardiovasc Electrophysiol, Vol. 15, pp. 1-5, June 2004)     

Long-term safety and efficacy of circumferential ablation with pulmonary vein isolation

Background: Each of the two main approaches to catheter ablation of atrial fibrillation (AF, segmental and circumferential) is associated with moderate long-term efficacy.
Objective: To report the long-term outcomes of a modified technique that combines circumferential ablation with pulmonary vein (PV) isolation, determined by a circular mapping catheter and to determine the relationship between complete PV isolation and long-term efficacy.
Methods: The patient population was composed of 64 consecutive patients (47 men [73%]; age 59 ± 11 years) with AF who underwent catheter ablation. AF was paroxysmal in 29 (45%) and nonparoxysmal in 35 (55%). Each patient was followed for a minimum of 12 months.
Results: After a mean follow-up of 13 ± 1 months, the long-term single-procedure success rate was 45% (n = 29) with an additional 4% (n = 3) of patients demonstrating improvement. With repeat procedures in 19 patients, the overall long-term success rate was 62% (n = 40) with 9% (n = 6) demonstrating improvement. All the patients who underwent repeat ablations had recovered PV conduction. Incomplete PV isolation was the only independent predictor of failure. A major complication occurred in four (6%) patients, including three patients with vascular complications and one with cardiac tamponade.
Conclusion: Our results suggest that the long-term single-procedure efficacy of circumferential ablation with PV isolation in a cohort of patients with predominantly nonparoxysmal AF approaches 50%. Repeat procedures involving re-isolation of the PVs result in a significant improvement in outcomes. Complete electrical isolation of the PVs has a significant impact on the long-term efficacy of the procedure.     

Curative therapy for swallowing-induced tachycardia by pulmonary vein antrum isolation

We present a case of a 49-year-old man who experienced invariably reproducible paroxysmal supraventricular tachycardia during swallowing. Because beta-blockers and multiple antiarrhythmic drugs failed to prevent the episodes of this tachycardia, we performed catheter mapping and ablation. After placing multiple decapolar catheters, when the patient swallowed a few sections of an orange, intracardiac mapping revealed atrial premature beats and atrial tachycardia that lasted for a few seconds and arose from an ostial site of the right superior pulmonary vein. After the right superior pulmonary vein antrum was completely isolated, the patient became free from the swallowing-induced tachycardia.     

Our approach to persistent atrial fibrillation in the setting of pulmonary vein isolation

In patients with persistent atrial fibrillation (AF) despite durable pulmonary vein isolation, there are a variety of approaches to further ablation. Here we summarize our strategy in this population. In brief, our approach is to isolate the posterior wall, ablate the coronary sinus musculature and left lateral ridge, complete a lateral mitral line, and achieve cavotricuspid isthmus block. Subsequently, we target organized atrial flutters and if AF persists, we ablate areas of long, fractionated electrograms within scarred regions. We administer isuprel in patients with a presentation consistent with triggered atrial fibrillation (low scar burden, paroxysms of AF).     

A new radiofrequency thermal balloon catheter for pulmonary vein isolation

OBJECTIVES: We sought to evaluate whether porcine pulmonary vein (PV) isolation (PVI) can be produced by ablation using our novel radiofrequency (RF) thermal balloon catheter (RBC). BACKGROUND: It has been proposed that PVI can prevent focal atrial fibrillation (AF) originating in or close to the PV. METHODS: The RBC is composed of a 12F main shaft, a 4F inner tube and a balloon. Inside the balloon, there is a unipolar coil electrode with a thermocouple sensor mounted along the tube, the former to deliver RF energy (13.56 MHz) and the latter to monitor the temperature. After the presence of a PV potential was confirmed, the RBC was safely inserted into the left atrium (LA) by the trans-septal approach. Once the balloon was inflated and optimally wedged at the junction between the PV and LA, RF energy was applied for 5 min. Radiofrequency catheter ablation (RFA) was repeated up to three times, until elimination of the PV potential or dissociation between the LA and PV was observed. Finally, each heart was examined histologically. RESULTS: In 18 PVs that had PV potentials, PVI was performed, resulting in success in 15 (success rate 83%, 95% confidence interval [CI] 58.0% to 96.3%; failure rate 17%, 95% CI 3.7% to 42.0%). After successful PVI, the PV potentials completely disappeared and the histologic examination revealed circumferential, transmural necrosis around the PV trunks. No major complications, such as PV stenosis or macroscopic thrombosis, were observed. CONCLUSIONS: The RBC was useful for PVI.     

Clinical predictors of arrhythmia recurrences following pulmonary vein antrum isolation for atrial fibrillation: predicting arrhythmia recurrence post-PVAI

Predicting Arrhythmia Recurrence Post‐PVAI . Introduction: Pulmonary vein antrum isolation (PVAI) is an accepted treatment for atrial fibrillation (AF) refractory to medical therapy. The purpose of this study was to identify the patient, procedural, and follow‐up factors associated with arrhythmia recurrences following PVAI. Methods and Results: Clinical data were prospectively collected on all 385 consecutive patients who had 530 PVAI (age 58 ± 11 years, 63% paroxysmal AF–PAF, follow‐up 2.8 ± 1.2 years) between February 2004 and March 2009. ECGs were recorded at each follow‐up visit with Holter monitoring 1, 3, 6, and 12 months following PVAI and every 6 months thereafter. Recurrences < 3 months post‐PVAI were defined as early, 3 months—1 year post‐PVAI as late, and > 1 year post‐PVAI as very late. Relationship between predictor variables and outcomes was modeled using Cox proportional hazards analysis. Late recurrences occurred in 42% with a lower rate among PAF versus non‐PAF patients (39% vs 56%, P = 0.001). Of the 256 patients with ≥ 1‐year follow‐up, 121 (47%) had no arrhythmia off antiarrhythmic drugs (AADs) 1 year post‐PVAI; 36 (30%) of these had a very late recurrence. In multivariate analysis, non‐PAF, hypertension, and prior AAD failure predicted recurrence. When entered into the model, early recurrences remained the only predictor of late recurrences. Conclusion: Patients with non‐PAF, hypertension, and prior failure of multiple AAD were more likely to experience arrhythmia recurrence post‐PVAI. Early recurrences were the strongest predictor of late recurrences. Late and very late recurrences following PVAI were common and should be considered when planning long‐term AF patient management. (J Cardiovasc Electrophysiol, Vol. pp. 1‐9)     

Radiofrequency catheter ablation of atrial fibrillation initiated by pulmonary vein ectopic beats

Ectopic beats from the pulmonary veins (PVs) have been demonstrated to initiate atrial fibrillation (AF). This article describes the conceptual approach to mapping, interpretation of different electrograms, and ablation of AF initiated by PV ectopic beats.     

Comparison of stent versus balloon angioplasty for pulmonary vein stenosis complicating pulmonary vein isolation

Introduction: Pulmonary vein stenosis (PVS) is a rare but significant complication of pulmonary vein isolation (PVI). Dilation and stent angioplasty have been described but not compared.
Methods and Results: All percutaneous interventions for PVS complicating PVI between December 2000 and March 2007 were reviewed. Acute success, defined as post-intervention stenosis ≤30%, and long-term outcome of dilation versus stent angioplasty were compared. Freedom from restenosis was defined as freedom from repeat intervention. Overall outcome for all interventions was examined. We studied 34 patients with 55 stenotic veins followed for a mean of 25 months. Dilation was performed in 39 veins and stenting in 40 veins (16 primarily, 24 after dilation restenosis). Acute success and restenosis rates were 42% and 72% for dilation versus 95% (P < 0.001) and 33% for stenting. Time to restenosis was greater for stent angioplasty (P = 0.003). Stents ≥10 mm in diameter had lower restenosis than smaller stents. Risk factors for restenosis included small reference vessel diameter and longer time from PVI to intervention for PVS. All but two patients experienced improvement (n = 10) or resolution of symptoms (n = 22). The mean percent stenosis decreased from 82% to 21% for the entire cohort and mean flow to the lung quadrant increased from 10% to 17%.
Conclusion: Stent angioplasty results in less restenosis than dilation, particularly for stents ≥10 mm. Early referral may improve long-term patency by minimizing reference vessel atrophy. Most patients with PVS post-PVI can be improved symptomatically with catheter intervention.     

导管射频消融治疗房颤时肺静脉电位振幅变化趋势的分析

目的 探讨肺静脉电位（PVP）指导的心房颤动（AF）射频消融治疗中PVP振幅（PVPA）与消融时间之间的关系以及不同类型AF在PVPA和消融时间之间是否存在差异。方法 连续选取2014年1月至2015年6月解放军总医院心内科住院且行肺静脉隔离（PVI）治疗的AF患者43例,按房颤类型分为阵发性AF组（n＝34）和持续性AF组（n＝9）,比较两组患者PVPA、消融时间以及术后12个月AF的复发率。结果 PVPA与消融时间之间存在线性相关,PVPA越大消融时间越长。两组患者在PVPA和消融时间上无显著性差异（P＞0.05）。持续性AF组复发率显著高于阵发性AF组（55.6% vs 17.6%,P＜0.05）。结论 在PVI治疗中,PVPA是指导消融的一个重要指标,但对于持续性AF患者除传统PVI外还应采取其他辅助消融策略,以提高其远期成功率。