心房颤动经导管消融的方法学研究

20世纪90年代以来,通过对心房颤动电生理机制研究的不断深入,导管消融治疗心房颤动技术得到迅速发展,各种导管消融策略不断出现。已在临床上广泛推广的消融策略包括以下几种:节段性肺静脉电隔离术、三维标测系统引导下的左房线性消融术、三维标测系统引导下肺静脉前庭环形电隔离术和心腔内超声监测下肺静脉前庭环形电隔离术。各种方法治疗成功率均达90%以上,使心房颤动根治成为可能。本文对各种导管消融方法进行综述。     

右位心经导管射频消融电隔离肺静脉治疗房颤1例的护理

导管射频消融电隔离肺静脉是应用射频能量消融诱发心房颤动的异位灶，从而根治心房颤动，是近几年来开展的一项安全而有效的新技术。近年来的心脏电生理研究证实，阵发性心房颤动多是由局灶性房性早搏触发或发动的，这些早搏大多起源于肺静脉，通过射频导管消融技术进行阵发性房颤相关的肺静脉电隔离，可以有效地防止心房颤动的复发。文献报道为正常心脏形态的病人，由于右位心心脏完全转位，结构与正常心脏位置发生改变，大大增加了手术的难度。我科2006年4月应用射频消融电隔离成功治疗1例阵发性房颤的右位心患者，现将护理体会报告如下。     

肺静脉与局灶性心房颤动

根据现有资料,绝大多数阵发性心房颤动(房颤)和一部分持续性房颤为局灶性机制,肺静脉肌袖快速电冲动的触发或驱动作用是局灶性房颤的主要发生机制之一。笔者就肺静脉及肺静脉肌袖的组织学、胚胎学、解剖学、电生理特征以及自主神经与局灶性房颤的关系简要综述。     

阵发性心房颤动的肺静脉电隔离治疗

目的 探索阵发性心房颤动的射频消融治疗方法及疗效。方法 对5例肺静脉起源的阵发性房颤患者，采用肺静脉内环状电极标测，温控导管对肺静脉电位进行射频消融，达到肺静脉完全电隔离。术后随访9～28个月，观察疗效。结果 5例患者电隔离治疗后，即刻成功率达100％；随访治愈2例，有效2例，无效1例，均无并发症发生。结论肺静脉电隔离治疗阵发性心房颤动是成功率较高，操作相对简单，比较安全的一种射频消融方法，有一定的发展前景。     

单中心球囊冷冻消融术后房性快速性心律失常的电生理标测和再消融治疗

目的 对阵发性心房颤动(简称房颤)患者行球囊冷冻消融后复发房性快速性心律失常的电生理机制进行初步探讨.方法 连续入选阵发性房颤行球囊冷冻消融后复发房性快速性心律失常、并行再次消融的患者.术中使用三维电解剖标测系统,先对左心房进行电压标测,判断各支肺静脉及肺静脉前庭是否仍有电传导,若有,则行射频消融,完成肺静脉及肺静脉前...     

心房颤动导管消融术式的进展

近年来对于肺静脉的"触发灶"作用和肺静脉前庭的"基质"作用的认识,大大促进了各种旨在消除心房颤动触发和维持机制的导管消融技术的发展.如节段性肺静脉电隔离术、环肺静脉线性消融术、左心房线性消融术以及最近提出的自主神经消融术和心房碎裂电位消融术等等,现综述如下     

犬肺静脉前庭在心房颤动中的作用

目的探讨左房快速起搏对肺静脉前庭电生理重构的影响。方法采用S1S2程序刺激,快速起搏左房的方法建立心房颤动模型,在起搏前及起搏后4h对左上、左下、右上、右下肺静脉前庭有效不应期进行测定,并进行房颤诱发,记录房颤发生率。结果在起搏4h或诱发房颤下与窦性心律相比各部位有效不应期明显缩短,差异有统计学意义（P〈0．05）,并且随着起搏时间延长,房颤的诱发率也增加（P〈0．05）。结论快速心房起搏引起肺静脉前庭电生理重构。     

三维电解剖标测指导环肺静脉线性消融治疗阵发性心房颤动

目的 探讨在Carto三维电解剖标测指导左心房环肺静脉线性消融治疗阵发性心房颤动的疗效。方法 对2例入选的阵发性房颤患者使用Carto系统建立左心房三维电解剖图,结合肺静脉造影确定肺静脉开口,围绕左、右上、下肺静脉口完成环肺静脉线性消融。预设温度43℃,最大功率30w,每点消融时间大于20s。局部电位振幅降低50％以上再移动靶点,逐点完成预定消融线。结果 2例患者操作时间分别为181min和193min,透视时间为60min和78min,放电次数120次和136次。术后随访8个月和1个月。例2在术后第3天再发房颤,但1个月内次数较前明显减少。2例患者均无肺静脉狭窄发生。结论 三维电解剖标测指导在左心房环肺静脉线性消融治疗阵发性房颤安全有效。     

三维标测系统指导下的肺静脉前庭隔离术

心房颤动(房颤)导管消融治疗的主要策略目前主要包括以下三种:肺静脉电隔离术、肺静脉前庭电隔离术和左心房线性消融术。肺静脉前庭(pu lmonary ve in antrun)指的是肺静脉开口和左心房体部之间,类似漏斗样扩张的区域,其边缘通常距离肺静脉开口约0.5~1.5 cm,但左肺静脉前庭的前缘往往与肺静脉开口重叠(图1)。传统意义上的左心房后壁实际上包括两侧肺静脉前庭在内,而真正的左心房后壁实际上只是位于两侧肺静脉前庭之间很小面积的一部分心房组织。以上三种消融策略的主要区别见表1和图2。除这3种主要消融策略之外,以心房内的碎裂电位作为靶点…     

电解剖标测系统加单环状电极导管指导环肺静脉前庭线性消融电隔离肺静脉治疗心房颤动

目的 探讨电解剖标测系统(CARTO)加单Lasso导管指导下行环肺静脉前庭线性消融电隔离肺静脉治疗心房颤动(房颤)的初步经验. 方法 3例房颤患者接受治疗,其中阵发性房颤2例,持续性房颤1例.所有患者首先用CARTO系统进行左房重建,然后将一根Lasso导管置入肺静脉内,在肺静脉口外5～10 mm处行环肺静脉前庭线性消融,消融终点为双侧肺静脉完全电隔离. 结果 3例患者均成功达到消融终点,手术时间(205±46)min,X线透视时间(46±13)min.手术过程中无并发症发生.术后随访7个月,3例患者均未再发房颤,均无出现肺静脉狭窄. 结论 在CARTO加单Lasso导管指导下行环肺静脉前庭线性消融电隔离肺静脉治疗房颤安全有效.     

Ectopic activity induced by elevated atrial pressure in rabbit pulmonary vein in vitro

Atrial fibrillation ( AF ) is a common tachyarrhythmia and may cause serious complications, such as stroke. When atrial pressure was elevated, the effect refraction period (ERP) was shortened and the conductivity in atria was slowed and the heterogeneity of different parts of atria was increased. These changes facilitate the occurrence and maintenance of AF.     

非接触三维标测系统指导下环肺静脉电隔治疗心房颤动的临床评价

目的:探讨非接触三维标测系统指导下环肺静脉电融隔离治疗心房颤动(房颤)的可行性和临床疗效.方法:28例药物治疗无效或不能耐受的房颤患者.其中23例阵发性房颤、5例持续性房颤.采用非接触三维标测系统(Ensite navX)建立左心房、肺静脉的三维等时电势图和电解剖图,并在距离肺静脉口1～2 cm处行环肺静脉及其周围组织电隔离.消融终点包括:完成所有环肺静脉消融径线;全部肺静脉均达电隔离;阴性诱发结果.结果:28例患者均达到消融终点;手术的总操作时间和X线曝光时间分别为(161.3±23.2)min和(38.0±6.8)min;随访6～17月,20例(71%)无房颤发作;8例(29%)有房颤复发,其中2例因其发作次数及时间均较术前明显减少未再消融,予以可达龙治疗可控制(术前可达龙治疗无效),6例行第2次消融,术中均发现肺静脉电位有不同程度的恢复,第2次术后4例房颤无再发,2例仍有发作但未再消融,予以可达龙治疗可控制.术中及随访期间无任何操作相关并发症.结论:非接触三维标测系统指导下的环肺静电隔离是治疗房颤的有效而安全的方法.肺静脉既是房颤的诱发机制,亦有可能参与房颤的维持.     

Carto merge技术指导永久性心房颤动射频消融

目的探讨Carto merge技术指导永久性心房颤动射频消融的作用和优势。方法用Carto merge技术指导射频消融治疗永久性心房颤动15例。术中用Carto导管标测和构建左心房和肺静脉的电解剖图,然后与术前心脏核磁共振造影的三维图像进行数据整合形成二者的复合图形(Carto merge)。首先在Carto merge的指导下行双侧上下肺静脉环线消融,直到Lasso标测证实所有肺静脉均达到电隔离效果,如心房颤动不终止,依次进一步消融左房顶部线、二尖瓣峡部线及三尖瓣峡部线,如上述部位消融后心房颤动仍未终止,即行同步直流电复律恢复窦性心律。结果15例患者中2例在消融过程中心房颤动自行终止,13例均经直流电复律。3例患者分别于术后24h、1和5周时复发持续性心房颤动。其余患者经1～10个月随访,均维持窦性心律。近期手术成功率为80%。结论Carto merge技术可有效地指导永久性房颤的射频消融,结合单Lasso标测,可简化操作,提高消融手术的成功率。     

Pulmonary vein tachycardia after pulmonary vein isolation in patients with atrial fibrillation

Background Pulmonary vein (PV) isolation has been developed to treat patients with atrial fibrillation (AF), and the electrophysiological endpoint of PV isolation is the disappearance or dissociation of pulmonary vein potentials (PVPs). Pulmonary vein tachycardia (PVT) is the dissociated PV rhythm with a rapid rate. However, the characteristics and significance of PVT after pulmonary vein isolation in patients with AF remains unclear. Methods From June 2003 to June 2005, a total of 285 consecutive patients with drug refractory AF were included in this study, and they underwent segmental pulmonary vein ablation (SPVA) or circumferential pulmonary vein ablation (CPVA). PV isolation was the initial endpoint for both approaches with documenting disappearance or dissociation of PVPs. PVT was characterized as dissociated activities within PVs with a circle length (CL) of <300 ms, and was classified into organized PVT or disorganized PVT according to the variance of CL. Systematic follow-up was conducted after initial procedures. Continuous variables were analyzed by Student’s t test and categorical variables were analyzed by chi-square test.Results Three hundred and fifteen PVs were ablated in 85 patients underwent SPVA approach, 400 circular lesions surrounding ipsilateral PVs (including 790 PVs) were produced in the rest of 200 patients received CPVA approach. Electrical isolation was achieved in all of these PVs. Of these, PVPs were abolished in 89.8% (992/1105) of the ablated PVs, dissociated PV rhythms were documented in the rest 10.2 % (113/1105) of the treated PVs. Among the 113 dissociated PV rhythms, 28 met the criteria of PVT with mean CL of (155±43) ms (2 PVTs in 2 patients received SPVA, 26 PVTs in 18 patients underwent CPVA). PVT was more frequently documented in patients underwent CPVA approach [9.0% (18/200) vs 2.3% (2/85), P=0.04]. During the 6-month follow-up, it was indicated that no significant difference existed in AF free rate between patients with PVT and those without PVT (P=0.75). Conclusions PVT dissociated from LA activations can be documented after PV isolation, especially in patients underwent CPVA approach. However, PVT does not affect the follow-up results.     

心房颤动对肺静脉肌袖结构影响的研究

目的：探讨心房颤动（atrial fibrillation,AF）时肺静脉肌袖结构的变化及其意义。方法：健康杂种犬17只,随机分为心房颤动组（11只）和对照组（6只）,应用快速心房起搏建立慢性房颤动物模型,通过HE染色、Masson 染色研究犬右上肺静脉的结构变化。结果：与对照犬相比,AF犬肺静脉肌袖内心肌细胞增大、排列紊乱;细胞核大小不甚规则,核异型性明显,细胞内可见肌纤维断裂;心肌纤维之间连接组织积聚,使心肌细胞之间的间隔增宽。从左心房到肺静脉方向,心肌袖组织逐渐变薄,末端肌束被纤维组织隔离。心肌袖内可见肌纤维方向突然改变,心肌细胞在长轴切片上显示为横断面,而在短轴切片上显示为纵切面。AF犬肺静脉肌袖内胶原组织较对照犬明显增多,排列紊乱,分布不均匀,围绕单个心肌细胞的胶原纤维网减少或断裂。结论：肺静脉肌袖结构的特殊性及其结构重构可能是形成肺静脉局部微折返的组织学基础,是AF发生和维持的重要机制。     

Linear ablation of left atrium for the treatment of atrial fibrillation guided by double Lasso catheters and three dimensional electroanatomical mapping

Catheter ablation for the treatment of atrial fibrillation (AF) was a topic of electrophy-siological study in recent years.1-4 Linear ablation of left atrium (LA) guided by three dimensional (3-D) electroanatomical mapping (Carto) has been widely accepted by electrophysiologists since the clinical use of 3-D mapping systems in catheter ablation of AF. However, the previous procedures of CPVA were mainly via pure anatomical approaches.5-8 While recent studies showed that complete isolation…     

Left atrial wall thickness: anatomic aspects relevant to catheter ablation of atrial fibrillation

Background  The success and complication rates of atrial fibrillation (AF) ablation may be related to regional differences in left atrial (LA) wall thickness. The purpose of this study was to investigate the transmural LA wall thickness in various regions.

Methods  We measured LA wall thickness in 36 human heart specimens using calipers at three planes including left pulmonary veins (PVs) vestibule plane, right PVs vestibule plane and the middle plane between the two. In each plane, eight points were selected, including superior, middle and inferior levels at anterior and posterior wall, roof and bottom.

Results  The anterior and posterior wall thickness displayed gradient from superior to inferior level (anterior wall: (2.73±1.01) mm, (2.08±0.91) mm and (1.54±0.69) mm; posterior wall: (1.74±0.68) mm, (1.48±0.39) mm and (1.27±0.42) mm). At the roof, LA wall thickness was thickest in middle plane ((2.01±1.02) mm) and was thinnest in left PVs vestibule plane ((1.29±0.41) mm). The posterior wall thickness in left PVs vestibule plane was thinner than in the other two planes (P <0.05–0.001), and was thinner in right PVs vestibule plane than in middle plane (P <0.01–0.001). Whereas in anterior wall, the wall thickness in left PVs vestibule plane was thicker than in middle and right PVs vestibule plane.

Conclusions  Significant variations exist for mean LA wall thickness at different regions which are often targeted during circumferential pulmonary venous ablation (CPVA). Appreciating these differences may have significant implications in catheter ablation of AF.

     

RADIOFREQUENCY CATHETER ABLATION OF PERMANENT ATRIAL FIBRILLATION UNDER GUIDANCE OF CARTO-MERGE TECHNIQUE

Objective To investigate the feasibility and effectiveness of radiofrequency catheter ablation (RFCA) to treat permanent atrial fibrillation (AF) under the guidance of Carto-Merge technique. Methods Fifteen male patients with permanent AF underwent RFCA under the guidance of Carto-Merge technique. The mean age was 54.00±10.44 years, and duration of AF was 23.66±14.93 months. Cardiac magnetic resonance angiography (MRA) was performed to obtain pre-procedural three-dimensional (3D) images on the anatomy of left atrium (LA) and pulmonary veins (PVs) before RFCA procedure. Then the electroanatomical map was integrated with 3D images of MRA to form Carto-Merge map that guided step-by-step ablation strategy of permanent AF. Circumferential PV ablation was performed first until complete PVs electric isolation confirmed by Lasso catheter. If AF was not terminated, lesion lines on roof of LA, mitral isthmus, and tricuspid isthmus were produced. Results The episodes of AF were terminated during RFCA in 2 patients, by direct current cardioversion in the remaining 13 patients. Transient AF occurred in 2 patients after ablation on 1st day and 1st week respectively, AF terminated spontaneously not long after taking metoprolol. One patient developed persistent atrial flutter (AFL) in 2 months after procedure and AFL was eliminated by the second ablation. Persistent AF recurred on 1st day, 1st and 5th week respectively in 3 patients, and did not terminate after 3 months even though amiodarone was given. The remaining 12 patients were all free of AF during 2-11 months of follow-up. The recent success rate for RFCA of permanent AF was 80%. Conclusions Carto-Merge technique can effectively guide RFCA of permanent AF. When combined with single Lasso mapping, it can simplify the mapping, lower expenses, and enhance the success rate of RFCA of permanent AF.     

导尿管引导双极消融钳技术在瓣膜置换同期房颤治疗中的应用

目的探讨心脏瓣膜置换术中应用双极射频消融治疗房颤更安全、简洁的操作技术。方法建立导尿管引导双极射频消融钳技术,观察在163例瓣膜置换同期消融治疗房颤患者中应用疗效,其中,男性55例,女性108例,年龄27～70岁,平均47.6岁,房颤病史均超过1年,最长15年,左心房最大内径45～80 mm,左心室内径43～74 mm,左心室射血分数40%～70%。本技术在常规体外循环下进行,体外循环转流后依次分离左、右肺静脉,先套过普通尿管,再以导尿管作为牵引,引导双极射频钳通过肺静脉后壁并完整包绕肺静脉,先进行左、右肺静脉消融隔离,再进行左侧上、下肺静脉,上、下肺静脉与左心耳之间的消融,缝闭左心耳,经左房或房间隔径路完成瓣膜置换手术,最后进行右心房消融。结果本技术在163例瓣膜置换术同期双极射频消融患者中应用,手术操作顺利,无组织撕裂,无术中意外出血,以及手术后再止血患者,死亡1例(0.6%),其余均顺利出院。结论该技术简化常规双极射频隔离肺静脉的手术操作技术,有效降低常规双极射频方法的手术风险,减少手术并发症,是一种有效的技术方法。