在心房颤动持续过程中行肺静脉电学隔离术的可行性

探讨在心房颤动 (简称房颤 )持续过程中行肺静脉电学隔离术的可行性。 9例在导管消融术中房颤持续发作的房颤患者 ,根据肺静脉环状标测电极导管记录的肺静脉激动特征采用 2种方法进行肺静脉开口部的消融 :①肺静脉激动有序且有一种或多种固定的激动顺序 ,采用射频导管消融环状电极记录的最早的激动部位 ;②肺静脉激动无序或无明确的激动顺序 ,首先使用超声球囊导管消融 ,如未达终点再加用射频导管消融。 2种方法的消融终点均为肺静脉电学隔离。总计对 31根肺静脉进行了消融 ,其中 2 8根在房颤心律下消融。房颤心律下电隔离肺静脉的成功率为 92 .9% (2 6根 )。总操作时间和X线透视时间分别为 1 38± 2 1min和 38± 9min。本组无肺静脉狭窄及其他并发症。随访 6 .3± 2 .9(3～ 1 1 )个月后 ,4例 (44.4% )患者无房颤发作 (无需药物 )。结论 :在房颤持续过程中行肺静脉电学隔离术方法可行 ,且较为安全 ;联用超声球囊消融和射频消融对于房颤发作过程中无序或无明确激动顺序的肺静脉具有较好的电学隔离效果。     

经球囊超声消融肺静脉治疗阵发性心房颤动的临床评价

目的　对经球囊超声消融肺静脉治疗阵发性心房颤动的效果和安全性进行临床评价。方法　阵发性心房颤动患者 4 7例 ,症状明显且抗心律失常药物治疗无效。经球囊超声消融左上肺静脉、右上肺静脉和左下肺静脉的开口 ,消融终点为肺静脉电学隔离。结果　总计消融了 137支肺静脉 ,肺静脉电学隔离 95支 (6 9 3% )。 4 4例患者的随访时间为 3～ 19(11 7± 5 1)个月 ,其中 18例(4 0 9% )患者可以无需药物而维持窦性心律。并发症包括 2例右侧膈神经麻痹、4例一过性心电图下壁导联ST段抬高和 2例严重迷走神经反射 ,无肺静脉狭窄。结论　现阶段阵发性心房颤动肺静脉超声球囊消融治疗的临床疗效和安全性可以接受。进一步改进球囊设计和以高温度 (6 0～ 6 5℃ )在肺静脉开口部消融 ,有助于提高成功率 ,减少并发症。     

冷冻球囊导管消融术的临床疗效及安全性分析

【】　目的　评价冷冻球囊导管消融术术的临床疗效及安全性。 方法　入选2014年6月至2015年6月华中科技大学附属同济医院就诊的38例阵发性房颤患者采用冷冻球囊技术进行房颤消融治疗。结果　房颤消融手术平均时间(125.5±38.2)min,平均透视时间(27.4±13.0)min,平均冷冻消融时间(36.9±12.8)min,导管消融即时成功率92.7%,平均每根肺静脉冷冻次数2～6(4. 0±1.2)次/根,各肺静脉即时成功率：左上肺静脉95.3%,左下肺静脉92.5%,右上肺静脉93.2%,右下肺静脉89.7%;术中行右上肺静脉消融时,并发膈神经麻痹1例,发生率2.6%;术后回访1例患者12个月内复发,复发率3%。结论　冷冻球囊消融术安全性高,具有良好的临床疗效     

环肺静脉线性消融电学隔离肺静脉治疗100例心房颤动临床评价

目的探讨三维标测系统和单环状标测电极指导下行环肺静脉线性消融电学隔离肺静脉治疗心房颤动(房颤)的可行性和有效性。方法自2004年4月至2005年1月共对连续100例症状明显、发作频繁、抗心律失常药物治疗无效的房颤患者进行了在CARTO系统(76例)或EnSite-NavX系统(24例)指导下的环肺静脉线性消融术,消融终点为双侧肺静脉的彻底电学隔离。结果100例患者共完成200个环形消融环,肺静脉电学隔离率为95.0%。操作时间150～365(240±65)min,X线时间为23～61(37±12)min。其中8例(8.0%)复发患者接受了再次导管消融。随访5.5～12(10.2±5.7)个月,累计无房性快速心律失常率为85.0%。术后1、2、3、4、5、6个月时无房性快速心律失常率分别为66.0%、82.0%、87.0%、85.0%、85.0%、88.6%。并发症包括1例心脏压塞,经保守治疗后康复,1例患者出现无症状性肺静脉狭窄。结论在三维标测系统指导下,环肺静脉线性消融电学隔离肺静脉治疗房颤安全有效。     

射频导管消融电学隔离心脏大静脉治疗阵发性心房颤动的临床应用

目的评价射频导管消融电学隔离心脏大静脉预防阵发性心房颤动(房颤)发作的疗效。方法83例患者,男性58例、女性25例,年龄15～76平均(605±185)岁,有阵发性房颤病史2～15年,曾服数种抗心律失常药物疗效不佳。41例患者合并有高血压病,所有患者均无明显器质性心脏病改变。常规行心脏大静脉造影,测量靶静脉直径,将10极肺静脉环状标测导管(Lasso导管)放置在靶静脉开口内05cm处,以Lasso导管为指导,把温控大头电极导管放置于靶静脉开口处行电学隔离。结果83例患者共电学隔离大静脉343条。包括左上肺静脉(LSPV)83条,右上肺静脉(RSPV)83条,左下肺静脉(LIPV)82条,右下肺静脉(RIPV)42条,上腔静脉(SVC)53条,其中2例LSPV与LIPV共同开口。每条肺静脉行1～4段消融(平均每条消融25段),即刻电学隔离成功大静脉337条。随访2～31个月,其中50例停服抗心律失常药物后无房颤发生,13例患者房颤发作明显减少,20例患者房颤发作消融前后无明显变化。并发症有2例术中出现左侧大量胸腔积血,1例心肺复苏5天后出现脑死亡。发现肺静脉狭窄21例,其中轻度狭窄15例,重度狭窄6例,无肺静脉闭塞。结论(1)成功的心脏大静脉电学隔离治疗阵发性房颤的总有效率达到75%左右;(2)由于很难确定靶肺静脉,成功电学隔离各心脏大静脉有可能提高治愈率;(3)此     

阵发性心房颤动经导管消融治疗40例报告

目的探讨经导管消融治疗阵发性心房颤动(房颤)的有效性和安全性。方法自2002年7月至2004年9月，对40例药物治疗无效的反复发作的阵发性房颤患者进行导管消融治疗。同步记录高位右心房、冠状静脉窦及肺静脉电图。采用3种不同的方法(节段性消融肺静脉电隔离术，Carto三维空间标测系统指导下肺静脉电隔离术，超声球囊肺静脉电隔离术)进行肺静脉电位的消融隔离。结果术后随访3—18个月。40例中27例(67．5％)经消融成功，3例(7．5％)有效，10例(25％)失败。Carto标测可减少X线曝光时间。消融过程中出现严重并发症为1例急性心脏压塞，经抢救存活。结论经导管消融治疗阵发性房颤是可行的，对大部分患者有效。     

肺静脉冷冻消融电隔离治疗心房颤动的即刻效果

目的探讨冷冻消融行肺静脉电隔离的即刻效果。方法选择临床确诊心房颤动(房颤)患者20例,阵发性房颤16例,持续性房颤4例。采用北极圈冷冻消融导管冷冻隔离肺静脉,Lasso导管标测肺静脉电位,肺静脉电位消失30 min为消融隔离成功。结果平均手术时间(265.88±52.20)min,曝光时间(43.42±17.23)min。实际电隔离57支肺静脉,平均每支肺静脉消融(5.64±2.57)次。2例持续性房颤在消融中终止,2例消融后电转复。7支肺静脉(占总消融肺静脉12.28%)在电位消失后30 min内恢复传导,再次行冷冻消融成功。消融即刻成功率100%。结论经导管冷冻肺静脉电隔离即刻效果较好。为减少复发,隔离后的等待时间是必要的。     

肺静脉电隔离治疗持续性心房颤动方法学及效果评价

目的对肺静脉电隔离治疗持续性心房颤动(房颤)的方法学及效果进行评价。方法14例持续性房颤患者,房颤病史6个月～20年,房颤持续时间1周～4个月,左心房直径37～47 mm平均(40．8±26．0)mm,左心室射血分数0．26-0．68平均0．55±0．11。术前抗凝治疗2～3周。术中常规放置冠状静脉窦导管及右心室起搏导管。房间隔穿刺成功后送入肺静脉环状标测电极导管(Lasso电极导管)及盐水灌注消融导管,预设功率30 W,温度50℃,于肺静脉口依次对4根肺静脉进行隔离。电复律恢复窦性心律后,再将Lasso电极导管依次送入各肺静脉口部标测,在残存肺静脉电位(PVP)的部位继续消融至心房与肺静脉完全电隔离。结果共对54根肺静脉进行电隔离,左上肺静脉14根,左下肺静脉13根,右上肺静脉14根,右下肺静脉13根,电隔离成功后PVP均完全消失,即刻成功率100％,平均放电时间(2 972±843)s。1例出现心脏压塞。随访12-18个月,无房颤复发5例(36％);症状明显减轻、房颤发作频率及持续时间明显减少4例(28％);症状无改善,房颤仍持续发作5例(36％),总有效率64％。结论肺静脉电隔离对持续性房颤治疗有效,其方法学可行但存在一定局限性。     

Lasso环形标测电极导管指导阵发性心房颤动肺静脉电隔离

探讨在Lasso环形标测电极导管指导下对阵发性心房颤动 (PAF)患者行肺静脉电隔离术的安全性、有效性。顽固性PAF患者 30例 ,男 19例 ,年龄 5 3± 15 (41～ 70 )岁 ,在肺静脉口用Lasso环形电极导管对肺静脉逐一进行标测 ,于肺静脉最早的心房 肺静脉电位处消融 ,电学隔离肺静脉。消融温度控制在 5 0℃ ,功率 2 5～ 35W。结果 :电学隔离肺静脉 6 9根 ,其中左上肺静脉 2 8根、左下肺静脉 2 0根、右上肺静脉 15根、右下肺静脉 6根 ,电隔离成功6 5根 ;电隔离上腔静脉 6根 ,左房后游离壁异位兴奋灶消融 8个 ,无手术相关并发症。即刻成功率 94 %。随访10 .1± 5 .1(5～ 2 2 )个月 ,成功率 (无心房颤动发作 ) 6 1%。结论 :在Lasso环形标测电极导管指导下对PAF患者行肺静脉电隔离术安全有效 ,是一种很有前途的治疗PAF的消融方法。     

老年人阵发性心房颤动的导管消融治疗

为评价老年人阵发性心房颤动 (PAF)行导管消融治疗的可行性和疗效 ,选择药物无法控制或不能耐受的PAF患者 5 6例 ,男 4 1例、女 15例 ,年龄 6 5 .7± 10 .1(6 0～ 74 )岁 ,无器质性心脏病 4 6例 ,合并高血压 7例 ,高血压及糖尿病 1例 ,高血压及冠心病 1例 ,冠心病 1例。均经食管超声心动图检查排除左房血栓。据消融技术的演进及患者入选的时间顺序 ,采用不同的消融方法 (点消融术、超声球囊肺静脉电隔离术、肺静脉节段性消融电隔离术 )。 3～ 6个月后评价疗效。结果 :5 6例患者 ,5 5例完成消融术 :点消融术 4例 ,成功 1例 ,无效 2例 ,心包积血 1例 ;超声球囊肺静脉电隔离术 14例 ,成功 7例 ,有效 5例 ,无效 2例 ,无肺静脉狭窄 ;肺静脉节段性消融电隔离术 37例 ,成功11例 ,有效 2 3例 ,无效 3例 ,左下肺静脉开口 >30 %狭窄 1例。结论 :导管消融治疗老年人PAF是安全有效的 ,肺静脉电隔离术使疗效明显提高 ,但仍未令人满意。     

三维标测系统指导下环肺静脉消融治疗心房颤动

目的 探讨三维标测系统指导下环肺静脉消融治疗心房颤动的安全性和有效性.方法 阵发性心房颤动92例和持续性或永久性心房颤动36例,接受环肺静脉消融术.采用Carto电解剖标测系统,进行环肺静脉左心房线性消融,消融终点为肺静脉电隔离.手术结束时对心律仍为心房颤动者行同步直流电心脏复律.结果 完成"解剖学"环形消融线256条,其中58.6%达到电隔离肺静脉的终点,经寻找缝隙补充消融后最终248条(96.9%)消融线达到终点.手术时间(231±45)min、X线曝光时间(42±13)min和放电时间(66±17)min.术后随访平均10个月,无复发101例(78.9%).接受了再次手术15例,心内电生理检查证实14例有左心房-肺静脉传导,射频消融成功并随访30～270 d,两次射频消融术后总成功率为87.5%,其中阵发性心房颤动成功率为93.0%,持续性或永久性心房颤动为76.7%.并发症发生率为6.2%,包括心包填塞2例、小脑梗死2例、股静脉穿刺部位血肿1例和左侧大量血胸1例,经治疗后均痊愈.结论 以肺静脉电隔离为目标的环肺静脉消融术治疗心房颤动有效和安全.     

双Lasso导管和三维标测指导下环肺静脉线性隔离术治疗心房颤动

目的在双Lasso导管和三维标测指导下环肺静脉线性消融并彻底隔离肺静脉以治疗心房颤动(简称房颤)。方法28例房颤患者接受射频消融治疗,其中阵发性房颤12例,持续性房颤16例。所有患者首先利用三维电解剖标测系统(CARTO)进行左房重建,然后将两根Lasso导管同时置入右(左)上下肺静脉内,在肺静脉口外0.5~1cm左右行环肺静脉线性消融,消融终点为左房-肺静脉完全性传导阻滞。结果28例均电隔离成功,肺静脉完成隔离后,共86.6%(97/112)的肺静脉内可见缓慢自律性电活动。手术时间205±67min,X线透视时间27±16min,无并发症发生。术后随访8.5±3.7个月,23例无房颤复发,总成功率82.1%。结论双Lasso导管和三维标测指导下有明确电学隔离指标的环肺静脉线性消融术治疗房颤安全而有效。     

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。     

Utility of exit block for identifying electrical isolation of the pulmonary veins

INTRODUCTION: Electrical isolation of the pulmonary veins (PVs) to treat paroxysmal atrial fibrillation (AF) has been described using "entry block" as an endpoint for PV isolation. We describe a new technique for guiding PV isolation, using "exit block" out of the PV after ablation as a criterion for successful isolation. METHODS AND RESULTS: A circular mapping catheter was positioned at the os of arrhythmogenic PVs and ablation was performed proximal to the mapping catheter until entry block into the vein was achieved. Pacing was performed from the mapping catheter and from the ablator inside the PV to document exit block out of the PV. In patients in whom cardioversion did not restore sinus rhythm, PV isolation was performed in AF. Entry and exit block were reassessed in ablated veins after a 20-minute waiting period. Ninety-five PVs were ablated in 41 patients. A total of 66 PVs in 34 patients were ablated in sinus rhythm. After entry block was achieved, exit block was present in only 38 (58%) of 66 PVs. A total of 29 PVs in 21 patients were ablated in AF. After cardioversion to sinus rhythm, there was evidence of entry block into the PV in 20 (69%) of 29 PVs and exit block in only 14 (48%) of 29 PVs. There was no significant difference between the total number of lesions applied per vein in sinus rhythm compared with AF (11.6 +/- 8.6 vs 10.3 +/- 6.2; P = NS). There was recovery of conduction after a 20-minute waiting period in 9 (11%) of 84 PVs. CONCLUSION: Identification of exit block after ostial PV ablation provides a clear endpoint for electrical isolation of the PVs. Isolation of the PVs can be performed during sustained AF without the need to apply excess RF lesions. Applying a 20-minute waiting period after electrical isolation will identify reconnection in approximately 10% of PVs.     

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.     

Single procedure efficacy of isolating all versus arrhythmogenic pulmonary veins on long-term control of atrial fibrillation: a prospective randomized study.

BACKGROUND: Current atrial fibrillation (AF) ablation involves isolation of all pulmonary veins (PVs) with or without additional linear lesions. However, whether such extensive ablation is necessary is unclear. OBJECTIVE: The purpose of this study was to assess the efficacy of different ablation strategies on long-term AF control. METHODS: We prospectively randomized patients to undergo isolation of all versus arrhythmogenic PVs (identified by standardized stimulation protocol). PV isolation was guided by circular mapping catheter. The endpoint was entry/exit block persisting for > or = 20 minutes. Patients were evaluated at three clinic visits (at 6 weeks, 6 months, and 1 year) and multiple transtelephonic monitoring periods. Antiarrhythmic drugs were discontinued at 6 weeks. Primary study endpoint was long-term AF control (freedom or >90% reduction in AF burden off or on previously ineffective antiarrhythmic drugs at 1 year after a single ablation procedure). RESULTS: Over a 20-month period, 105 patients (76 men and 29 women, age 57 +/- 9 years; paroxysmal AF = 77) were randomized, and 103 patients completed 1-year follow-up (51 patients in all-PV arm, 52 patients in arrhythmogenic PV arm). The primary endpoint was achieved in 75 (73%) patients and was similar in patients randomized to all-PV arm versus arrhythmogenic PV arm [38 (75%) patients vs 37 (71%) patients, respectively; odds ratio 1.18, 95% confidence interval 0.50, 2.83, P = .70]. Secondary study endpoints, including freedom from AF off antiarrhythmic drugs, total procedure/fluoroscopy times, and occurrence of serious adverse events, were not different between the two groups. CONCLUSION: In a randomized comparison, isolation of arrhythmogenic veins was as efficacious as empiric isolation of all veins in achieving long-term AF control.     

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.     

阵发性心房颤动患者肺静脉前庭电生理现象及分析

目的采用EnSite/NavX系统指导下,结合单Lasso进行环肺静脉电隔离术治疗阵发性心房颤动(简称房颤),分析消融过程中肺静脉前庭电生理现象。方法入选2004年10月~2005年12月症状性阵发性房颤患者143例,男85例、女58例,年龄60.7±10.3(35~80)岁,房颤病程5.5±6.7年(21天~50年),左房内径36.9±6.4(24~54)mm。在EnSite-NavX系统引导下行环肺静脉消融达到肺静脉电隔离。结果143例完成环肺静脉隔离术,手术时间157±30(90~240)min,放射线时间25.8±8.8(9.8~60.1)min。环单侧左、右肺静脉前庭消融电隔离率分别为81.2%、78.3%,其余病例结合节段性消融(SOA)达到肺静脉电隔离。房颤终止的比例为69.7%(23/33例),第一次消融63.6%(91/143)可记录到肺静脉内自发电位,2.1%(3/143)可记录到肺静脉内快速的自主节律,而体表心电图为稳定的窦性心律。房颤复发患者第二次消融时,所有21例均有肺静脉电位(PVP)恢复,其中第一次消融时结合SOA达到肺静脉隔离的患者:57.1%左侧PVP恢复,55.6%右侧PVP恢复。第二次消融时,85.7%(18/21)例存在肺静脉内自发电位。术后房性心动过速/心房扑动15例(10.5%),12例再次行射频消融治疗,11例消融成功。术后随访10.7±4.9(4~18)个月,包括第二次消融术后患者在内,共90.2%(129/143)在无抗心律失常药物治疗下无房颤发作。心包积液2例,Ensite/NavX电极贴片故障1例。结论心房-肺静脉传导存在优势传导径路,且传导方式并非“全或无”;结合SOA的消融方法复发率较高;多数患者肺静脉隔离后可记录到自发肺静脉电位,复发患者的肺静脉通常具有较高的兴奋性。     

Initial experience using a forward directed, high-intensity focused ultrasound balloon catheter for pulmonary vein antrum isolation in patients with atrial fibrillation

Background: A high-intensity-focused ultrasound balloon catheter (HIFU-BC) is designed to isolate pulmonary veins (PV) outside the ostia (PV antrum). This catheter uses a parabolic CO₂ balloon (behind water balloon) to focus a 20-, 25-, or 30-mm diameter ring of ultrasound forward of the balloon (parallel to catheter shaft). The purpose of this study is to test the safety and efficacy of the HIFU-BC for PV antrum isolation in patients with atrial fibrillation (AF).
Methods and Results: Twenty-seven patients with paroxysmal (19 patients) or persistent (8 patients) AF were studied. Double transseptal puncture was performed for left atrial deployment of a Lasso catheter (for PV mapping) and the 14 Fr HIFU-BC. The HIFU-BC was positioned outside the PV orifice over a guidewire. HIFU energy (acoustic power 45 watts) was applied for 40 seconds with a 20-mm sonicating ring and 40 or 60 seconds with a 25-mm or 30-mm sonicating ring. No other ablation system was utilized. PV antrum isolation was attempted using HIFU-BC in 78 of 104 PVs (25/27 RSPVs, all 23 LSPVs, all 23 LIPVs, all four left common trunks and 3/27 RIPVs). HIFU-BC successfully isolated 68 (87%) of the 78PV antra with 1–26 (median 3) HIFU applications. The complications include transient bleeding from a distal branch of the left superior PV resulting from guidewire manipulation in one patient and right phrenic nerve injury in another patient. No PV stenosis (>50% narrowing) and no LA-esophageal fistula occurred. At the 12-month follow-up, 16 (59%) of the 27 patients were free of symptomatic episodes of AF (only 3 of the 16 patients were receiving antiarrhythmic medications).
Conclusions: Forward-focused HIFU applications isolated PVs outside the PV ostium with elimination of AF in 16 (59%) of the 27 patients at 12 months following the single ablation procedure.