脉冲电场消融治疗房颤的现状

目前,导管消融术（catheter ablation,CA）已成为国内外治疗药物难治性房颤患者的主要方法,尤其是肺静脉隔离术（pulmonary vein isolation,PVI）,已成为CA治疗的基石。无论是导管的阻抗热损伤还是球囊的冷冻消融,两大能源仍存在膈神经损伤、心房食管瘘、心包填塞等不可逆的安全问题。脉冲电场消融（pulsed field ablation,PFA）,作为一种电脉冲能源,是治疗心律失常最新的消融技术热点话题。PFA通过释放短时程、高电压的电脉冲能量对细胞产生不可逆电穿孔,导致细胞凋亡,对心肌造成不可逆的损伤,发挥肺静脉隔离的作用。其优点主要是避免冠状动脉、食管、肺静脉及膈神经等周围组织受到损伤,比常规房颤消融方法更具有效性及安全性。本文对PFA的特点展开综述,详细阐述其治疗房颤的优势。     

重视心房颤动非肺静脉触发灶的导管消融

导管消融已逐渐成为心房颤动(房颤)治疗的有效手段,如何降低术后复发率是当前面临的挑战之一。肺静脉隔离是房颤导管消融治疗的基石,但是非肺静脉触发灶在房颤的触发和维持中发挥一定作用,是房颤术后复发的主要预测因子。消融非肺静脉触发灶有助于减少阵发性和非阵发性房颤术后心律失常复发率。     

持续性心房颤动导管消融方法及策略

心房颤动是临床上最常见的心律失常,其节律控制治疗主要有药物治疗和非药物治疗两种方式。目前非药物治疗心房颤动发展迅速,其中导管消融作为非药物治疗心房颤动手段之一已被人们广泛接受。肺静脉电隔离作为阵发性心房颤动的消融终点已经得到共识,而持续性心房颤动消融术式及终点尚未统一,现就目前持续性心房颤动消融方法及策略做一简要介绍。     

环肺静脉电隔离术中自发电位传出导致的房性心律失常的再次消融及其评价

目的 分析心房颤动(房颤)环肺静脉电隔离术中出现肺静脉自发电位传出导致房性心律失常的发生及其再次消融评价.方法 在三维标测系统指导下行环肺静脉电隔离及辅助线、碎裂电位等消融治疗房颤,术中观察分析导致房性心律失常的肺静脉自发电位,对靶肺静脉行补充消融达完全电隔离并对其再评价.结果 术中5根肺静脉出现自发电位,但证实肺静脉与心房之间为单向阻滞,仔细观察分析对靶肺静脉进行再次消融均达到完全电隔离且再无肺静脉相关性房性心律失常.结论 环肺静脉电隔离中肺静脉内出现自发电位仅说明心房至肺静脉的传导阻滞,仍可存在肺静脉内自发电位传出导致房性心律失常,术中需仔细分析鉴别并对靶静脉消融隔离以减少术后房性心律失常发生.     

脉冲电场消融治疗心房颤动的研究进展

导管消融是治疗各种快速性心律失常的主要手段之一,其中射频消融和冷冻消融是目前公认的心房颤动导管治疗方式,其疗效确切,但也存在一些并发症风险。脉冲电场消融是一种有高度组织选择性的新型消融方式,前期动物实验和临床试验已经评估了其在肺静脉隔离中的有效性、安全性及高效性,在真实世界研究中也取得较为满意的效果。脉冲电场消融有望广泛应用于心房颤动的治疗。     

射频导管消融根治合并多机制房性心律失常的心房颤动1例

环肺静脉线性消融是目前心房颤动射频导管消融(下称消融)最主要的策略.但在消融过程中有部分患者会出现或转变为房性心动过速或心房扑动等其他房性心律失常,其发生由多种机制产生,主要包括缝隙相关性、消融线相关性以及非消融相关性的房性心律失常等.本文报道1例包含多种机制的心房颤动消融根治房性心律失常.     

冷冻球囊导管消融术在心房颤动治疗中的应用

心房颤动（房颤）是最常见的持续性心律失常;目前其主要治疗方法包括药物治疗、导管消融治疗和外科手术治疗。近年来导管消融术得到快速发展,显示出良好的应用前景,其中环肺静脉隔离术是一种应用广泛的术式,所用能源主要为射频能源,但手术复杂,学习曲线较长,可出现血栓形成、心肌及其周围组织损伤、致命性肺静脉狭窄及心房—食道瘘等并发症,限制了该术式的普及。     

经皮导管冷冻消融治疗阵发性心房颤动的临床应用

目的:探讨导管冷冻消融术治疗心房颤动的有效性及安全性.方法:对12例阵发性心房颤动患者进行冷冻消融治疗.评价导管冷冻消融术治疗心房颤动的急性成功率、术后并发症以及临床长期有效性.结果:12例阵发性心房颤动患者,共对44根肺静脉进行了冷冻消融,其中29根肺静脉单用环状冷冻导管消融4～6次即能达到肺静脉的完全电隔离,15根肺静脉用环状冷冻导管消融后,需用普通射频消融导管在环形冷冻线上补点消融后才成功隔离肺静脉.随访6～10个月,9例临床症状得到改善,无心房颤动复发,其中3例需服用抗心律失常药维持窦性心律.3例患者心房颤动复发.消融后即刻选择性肺静脉造影和术后6个月核磁共振扫描检查均未发现肺静脉狭窄.结论:经皮导管冷冻消融治疗阵发性心房颤动是安全、有效的,可作为治疗心房颤动的一种有效方法.     

射频消融术与冷冻消融术对凝血系统影响的研究进展

自从射频消融术治疗心律失常问世以来,由于其成功率和安全性高,迅速在世界各地广泛推广. 随着技术的进步和临床操作水平的提高,目前射频消融术已成为临床治疗快速性心律失常的一线治疗方法.近年来冷冻消融术也作为一种新的消融能源,开始在国内外应用于临床心律失常的消融治疗,其疗效也得到了临床实践和实验证实.与射频消融相比,在房颤的消融术中,冷冻消融术是一种安全无痛的术式,肺静脉狭窄的风险很低,特别是靠近房室结的部位消融,房室传导阻滞的发生率极低[1],是一种新的心律失常安全消融能源[2,3].现就射频消融术和冷冻消融术对凝血系统的影响综述如下.     

阵发性心房颤动导管消融术后早期复发的电生理机制和再消融

目的 评价阵发性心房颤动(房颤)导管消融术后早期复发的电生理机制及早期再消融的可行性、疗效.方法 入选环肺静脉电隔离术后1个月内复发的阵发性房颤患者14例,其中男8例,女6例,平均年龄61.8±8.4岁,房颤复发距首次消融时间4.9±3.7 d.若肺静脉传导恢复,则补点消融再次隔离.肺静脉隔离后诱发房颤,标测并消融非肺静脉异位灶.术后随访心电图和24 h动态心电图.结果 14例患者首次消融后24.7±5.5 d再次消融.仅1例肺静脉传导无恢复,其余13例(92.9%)中均有至少一侧肺静脉传导恢复,补点消融后均再次隔离.3例(21.4%)为上腔静脉起源房颤,行上腔静脉隔离房颤终止.1例(7.1%)为界嵴上部起源,行局灶消融成功.3例诱发出典型心房扑动(房扑),1例诱发出左心房房扑,消融均成功.术后平均随访5.8±1.4个月,13例患者无房性快速性心律失常复发(不用抗心律失常药物),1例有阵发性房速发作(服用维拉帕米).结论 肺静脉传导恢复是阵发性房颤消融术后早期复发的主要因素,其次是非肺静脉(上腔静脉、界嵴)的异位灶,早期再消融可行有效.     

Arrhythmia Recurrence After Atrial Fibrillation Ablation: Can Magnetic Resonance Imaging Identify Gaps in Atrial Ablation Lines?

After pulmonary vein isolation for the treatment of atrial fibrillation, clinical arrhythmia recurrence is often a result of vein reconnection. By selectively visualizing scarred tissue, delayed enhancement magnetic resonance imaging may provide for a noninvasive means to identify gaps in radiofrequency ablation lines. This report correlates three-dimensional magnetic resonance imaging with invasive electroanatomical mapping in a patient with recurrent atrial arrhythmia after multiple unsuccessful ablations for atrial fibrillation.     

Current Endovascular Approach in Adult Patients with Pulmonary Vein Stenosis: A State-of-the-Art Approach

Regarding to more invasive treatment of atrial arrhythmia (atrial fibrillation ablation) and pulmonary vein isolation (PVI), the rate of acquired pulmonary vein stenosis (PVS) is increasing and at present, PV ablation for AF has become the principal cause of PVS in adult patients. On the other way, by improvement in procedural techniques, equipment, and the experience of the operators, the incidence of PVS has been decreased. There is some controversy about the manner of follow-up of these patients and in most centers, just symptomatic patients are considered for imaging and treatment. Almost always, those with PV stenosis more than 70% or multiple PV involvement become symptomatic and if give them up without treatment, pulmonary symptoms and finally irreversible pulmonary hypertension will occurred. So, intensive pursue after the procedure is highly recommended. Whereas in pediatric patients with congenital or acquired PVS, the best treatment approach is surgery, in adult patients, the preferred type of treatment is the transcatheter intervention with high acute success rate. In this present review, we have scrutinized about the diagnostic modalities, the indications for intervention, the diverse treatment strategies, and principally clarify an accurate stepwise approach during transcatheter procedure.     

Irreversible electroporation of the pancreas in swine: a pilot study

Background:

Irreversible electroporation (IRE) is a novel, non-thermal method of tissue ablation using short pulses of high-voltage DC current to ablate tissue.

Methods:

Irreversible electroporation of the pancreas was performed in four domestic female swine using two monopolar probes spaced 9–15 mm apart. Ninety pulses of 1500 V/cm were delivered for each ablation.

Results:

All animals survived for their designated times of 2 h (n= 1), 2 days (n= 1) and 14 days (n= 2), respectively. No procedure-related complications occurred. Three animals in which probes had been spaced at intervals of 10 ± 1 mm showed evidence of irreversible ablation, with ablation height ranging from <10 mm to 21 mm and ablation width ranging from <10 mm to 16 mm by gross appearance and triphenyltetrazolium chloride (TTC) staining. The only animal in which probes had been spaced at intervals of 15 mm did not show evidence of irreversible ablation at 2 weeks. This may be secondary to the wider probe spacing and relatively low voltage, which results in a mostly reversible form of electroporation without cell death.

Conclusions:

Irreversible electroporation appears to be a safe method for pancreas tissue ablation. Staining with TTC can predict the zone of IRE ablation within 2 h of treatment.     

Pulsed field ablation for pulmonary vein isolation in the treatment of atrial fibrillation

Pulsed‐field ablation (PFA) is a promising new ablation modality for the treatment of atrial fibrillation. This energy form employs a train of microsecond duration high amplitude electrical pulses that ablate myocardium by electroporation of the sarcolemmal membrane without measurable tissue heating. The ablation pulse waveform has multiple variable components that can affect ablation efficacy, thus each proprietary system has unique properties that cannot be generalized to other systems. Success with PFA depends upon the proximity of the electrode to the target tissue, but not necessarily upon contact. A unique feature of PFA is tissue specificity. Myocardium is very susceptible to irreversible injury whereas the esophagus, phrenic nerves, pulmonary veins, and coronary arteries are relatively resistant to injury. The tissue specificity of PFA may result in a wide therapeutic range and improved safety profile during atrial fibrillation ablation. Vein isolation can be achieved very rapidly (seconds) promising that PFA may reduce procedure time to 1 hour or less. This attractive new technology promises to be a major advance in the field of atrial fibrillation ablation.     

体表心电图对肺静脉起源的房性心律失常中的应用

心房颤动(AF)是心脏疾病中最常见的心律失常。本文对体表心电图对肺静脉起源的房性心律失常中的应用作一综述。     

Current status and future catheter ablation strategies in atrial fibrillation

Catheter ablation of atrial fibrillation (AF) is a highly effective therapy to achieve freedom of recurrent arrhythmia and relief from symptomatic AF. Transmural ablation of atrial tissue is crucial for success. Thus steerable sheaths and catheter design with contact measurement as an additional feature have been developed to increase success rates. New 3 dimentional (3D) mapping technologies engage clinical routine to reduce fluoroscopy time and radiation dose for patients and medical staff to a minimum. To unmask dormant pulmonary vein reconduction and to avoid early pulmonary vein reconduction administration of adenosine is useful. Future approaches aim at individualized ablation strategies taking clinical and electrophysiologic characteristics of the individual patient into account.     

Hepatocellular carcinoma: new options for image-guided ablation

Image-guided percutaneous ablation is currently accepted as the best therapeutic choice for patients with early-stage hepatocellular carcinoma (HCC) when transplantation and resection are precluded. Several methods for chemical or thermal tumor destruction have been developed and tested clinically during the past two decades. The seminal technique used for local treatment of HCC has been percutaneous ethanol injection (PEI). Several studies have provided indirect evidence that PEI improves the natural history of nonsurgical patients with early-stage HCC. Its major limitation is the high rate of local recurrence. Radiofrequency (RF) ablation has been the most widely assessed alternative to PEI. Five randomized controlled trials have shown that RF ablation achieves more effective and reproducible tumor destruction than PEI, leading to a better local control of the disease. As a result, RF ablation has been established as the primary ablative modality. The value of newer thermal and non-thermal methods for local tumor treatment, such as microwave ablation, irreversible electroporation (IRE), and light activated drug therapy, should be investigated in the setting of randomized controlled trials.     

New technologies and therapies for cardiac arrhythmias

Catheter ablation of cardiac arrhythmia has evolved to an important treatment modality for patients with various cardiac rhythm abnormalities. Over the past three decades, the understanding of arrhythmia mechanisms and technology for catheter based diagnostic and ablation procedures have evolved rapidly. New technologies and therapies for treatment of cardiac arrhythmia include ablation catheters designed to destroy targeted tissue with improved precision and safety, robotic systems to guide accurate catheter movements, electrical mapping systems, and improved imaging to complement such systems. This review focuses on improved imaging modalities used in the modern electrophysiology laboratory.     

Acute pulmonary vein isolation is achieved by a combination of reversible and irreversible atrial injury after catheter ablation: evidence from magnetic resonance imaging

Background- Pulmonary vein reconnection after pulmonary vein isolation is common and is usually associated with recurrences of atrial fibrillation. We used cardiac magnetic resonance imaging after radiofrequency ablation to investigate the hypothesis that acute pulmonary vein isolation results from a combination of irreversible and reversible atrial injury. Methods and Results- Delayed enhancement (DE; representing areas of acute tissue injury/necrosis) and T2-weighted (representing tissue water content, including edema) cardiac magnetic resonance scans were performed before, immediately after (acute), and later than 3 months (late) after pulmonary vein isolation in 25 patients with paroxysmal atrial fibrillation undergoing wide-area circumferential ablation. Images were analyzed as pairs of pulmonary veins to quantify the percentage of circumferential antral encirclement composed of DE, T2, and combined DE+T2 signal. Fourteen of 25 patients were atrial fibrillation free at 11-month follow-up (interquartile range, 8-16 months). These patients had higher DE (71±6.0%) and lower T2 signal (72±7.8%) encirclement on the acute scans compared with recurrences (DE, 55±9.1%; T2, 85±6.3%; P<0.05). Patients maintaining sinus rhythm had a lesser decline in DE between acute and chronic scans compared with recurrences (71±6.0% and 60±5.8% versus 55±9.1% and 34±7.3%, respectively). The percentage of encirclement by a combination of DE+T2 was almost similar in both groups on the acute scans (atrial fibrillation free, 89±5.4%; recurrences, 92±4.8%) but different on the chronic scans (60±5.7% versus 34±7.3%). Conclusions- The higher T2 signal on acute scans and greater decline in DE on chronic imaging in patients with recurrences suggest that they have more reversible tissue injury, providing a potential mechanism for pulmonary vein reconnection, resulting in arrhythmia recurrence.