心腔内超声评价希氏束起搏心脏血流动力学和解剖结构重构

目的采用单一的心腔内超声心动图和组织多普勒显像技术检测和评价直接希氏束起搏诱导的心室激动顺序、心脏解剖结构和血流动力学重构.方法六只急性闭胸直接希氏束起搏狗模型.采用美国Medtronic导向引导鞘管和主动螺旋电极,在心腔内超声心动图和组织多普勒显像技术引导下将起搏电极分别置放于希氏束(n=6)和右室心尖(n=6).所有部位的起搏频率均控制为120次/min.采用二维灰阶、血流频谱多普勒和组织多普勒技术,分别测量和计算心脏不同部位起搏时心室各房室和相连大血管解剖结构内径和容量、心肌的激动顺序和相关血流动力学参数,并进行不同起搏状态上述测量参数的配对统计比较.结果希氏束起搏状态下,左心室壁内心肌的激动顺序、心脏主要解剖结构和血流动力学参数与窦性心律状态下相同参数比较无显著性差异;与右心室心尖起搏状态下相同参数比较有显著性差异.结论单一的心腔内超声和组织多普勒技术能够有效地量化评价心脏起搏状态下的心脏解剖结构和血流动力学改变.与右心室心尖部起搏相比较,希氏束起搏能够明显地改善心脏解剖和血流动力学重构.     

房室结和房室束的临床应用解剖

在26个（胎儿8．成人5，狗5，兔8）心脏标本上用连续切片光镜观察和测量了房室结和房室束的形态和位置成人房室结中份额状面上呈半椭圆形、扁平形或梭形，胎儿呈肾形。成人房室结大小为3．7mm×3．5mm×1．0mm。胎儿31．1mm×1．8mm×0．6mm，狗2．1mm×2．4mm×0．6mm，兔2．1mm×1．2mm×0．4mm。成人房室束大小为7．4mm×2．2mm×1．2mm。成人房室结向后距冠状窦口前缘3．0～4．0mm，离右心房内侧面0．2～0．6mm，位于三尖瓣隔侧瓣上缘1．7～5．5mm。本文讨论了这些结构的临床意义。     

房室结和房室束的临床应用解剖

在２６个（肿儿８，成人５，狗５，兔８）心脏标本上用连续切片光镜观察和测量了房室结和房室束的形态和位置。成人房室结中份额状面上呈半椭圆形、扁平形或梭形，胎儿呈肾形。成人房室结大小为３．７ｍｍ×３．５ｍｍ×１．０ｍｍ。胎儿为１．１ｍｍ×１．８ｍｍ×０．６ｍｍ，狗２．１ｍｍ×２．４ｍｍ×０．６ｍｍ，兔２．１ｍｍ×１．２ｍｍ×０．４ｍｍ。成人房室束大小为７．４ｍｍ×２．２ｍｍ×１．２ｍｍ。成人房室结向后距     

希氏束旁旁路导管射频消融治疗

32例电生理检查确诊为希氏束旁旁路患者,其中22例显性旁路,10例隐性旁路.窦律下采用温控消融,从小功率20W短时间(5s)开始.结果32例患者除2例担心手术风险拒绝消融治疗外,余30例全部行射频消融治疗并获得成功.温度55～60℃功率20～40W,消融时间60s,重复诱发无心动过速,术后随访3～12月无复发.未发生并发症,随访至今,无1例复发.窦律下消融希氏束旁旁路安全有效.三维电解剖标测系统有助于指导其消融.     

34例希氏束起搏患者的术后观察

希氏束起搏更接近于生理性起搏,比传统的右室心尖部起搏更有优势。总结34例经希氏束起搏患者术后的观察与护理,术后动态观察生命体征、起搏器起搏与感知功能、伤口及囊袋愈合情况,重视并发症的预防性护理,及时发现患者细微的病情变化,及时处理是治疗成功的关键。     

射频消融难以阻断房室结-希氏束2例

1病历摘要女,65岁。临床诊断:(1)老年瓣膜退行性心脏病、心房纤颤、心动能级;(2)高血压病、3级高血压、极高危组。超声心动图报告:左房内径5.72 cm,右房内径7.5 cm×9.37 cm,右室舒张期内径2.66 cm,左室舒张期内径6.54 cm。例2:女,55岁。临床诊断:甲减性心脏病、心房纤颤、心功能级。超声心动图报告:左房内径5.46 cm,右房内径9.36 cm×6.9 cm,右室舒张期内径4.65 cm,左室舒张期内径2.15 cm。2讨论本文2例均属难治性房患者。对此类型患者行房室结-希氏束频消融阻断并植入单腔人工心脏永久起搏器,其疗效及手术安全性目前已得到公认。传统射频…     

锁骨下静脉穿刺心腔内心电图引导临时起搏术的配合

紧急床边临时心脏起搏术在严重心动过缓、心脏骤停等的抢救中能及时恢复正常心率，维持血流动力学，从而为进一步治疗奠定了基础。我院自1993年7月-1997年6月采用锁骨下静脉穿刺心腔内心电图引导的方法，为52例危重患者于床旁紧急植人临时起搏器，赢得了抢救时间，挽救了患者的生命。这一治疗方法对护理人员提出了更高的要求。现将手术的配合及护理介绍如下。1临床资料52例患者均住冠心病监护病房，男36例，女16例，年龄13－79岁，急性下壁心肌梗塞或原发高度或完全性房室传导阻滞29例，病态窦房结综合征引起严重心动过缓（HR＜35次／min）…     

永久希氏束起搏98例的术后护理

总结98例患者植入永久希氏束起搏器术后的护理体会。术后做好术侧肢体的护理,应用心电监护仪加强监测,密切观察心电图波形,观察病情变化,同时做好生活护理,加强健康指导。98例患者经成功植入永久希氏束起搏和术后合理的护理管理,均好转出院,其中3例心力衰竭患者近期和远期心功能较术前明显好转,1例心脏再同步治疗适应证患者心脏几乎恢复正常,1例患者术后出现中等量心包积液,未予处理自行吸收。     

1例房室结射频消融并双心室起搏病人的护理

多部位起搏治疗充血性心力衰竭是20世纪末在国际上兴起的一种新的治疗方法,国内已有报道。我科于2001年11月为1例扩张型心肌病、心功能Ⅳ级并心房纤颤及完全性左束支传导阻滞患者行房室结消融并双心室起搏,在护理的密切配合下,取得了良好的疗效。现将护理体会报道如下。     

心腔内心电图监测经锁骨下静脉床旁临时心脏起搏术

心腔内心电图监测经锁骨下静脉床旁临时心脏起搏术杨丽华，杨树森，王岚峰，赵进军，孟繁超经股静脉径路实施临时心脏起搏以其方法安全而广泛应用于临床。近年来我们在无Ｘ线监视情况下对１５例患者采用锁骨下静脉径路进行临时心脏起搏，取得良好效果，报告如下。资料和方...     

Intracardiac echocardiography-guided his bundle pacing and atrioventricular nodal ablation

Background: His bundle pacing (HBP) results in rapid synchronous ventricular activation, but has been associated with long procedure times and compromised pacing and sensing performance. This study sought to reduce procedure time and radiation exposure, and improve electrical performance through more accurate lead placement.
Methods: Intracardiac echocardiography (ICE) was used to guide ablation and lead implantation at the His bundle, right atrial appendage (RAA), and right ventricular apex (RVA), and to assess cardiac function. Custom bipolar screw-in leads with steerable delivery sheaths and an ablation catheter were navigated using ICE (local detailed imaging) and fluoroscopy (global imaging) in anesthetized closed-chest canines (N = 6).
Results: HBP (N = 1) or His + ventricular septal pacing (N = 5) was achieved in all canines. The QRS width was 59.7 ± 5.3 ms for canines in sinus rhythm (SR) and 82.8 ± 16.6 ms for canines with HBP (P = 0.0086). The QRS width for RVA pacing was 106.3 ± 18.4 ms (P = 0.042 vs HBP; P = 0.00013 vs SR). HBP thresholds were 3.0 ± 1.0 volts at 0.5 ms (N = 5 due to a late exit block in one canine). The average procedure duration for His lead placement was 40 ± 28 minutes (range of 3–81 minutes) and the total procedural X-ray exposure was 12 ± 12 minutes (range of 2–30 minutes). Hemodynamic performance was similar for HBP and RAA pacing.
Conclusions: Feasibility of ICE guidance for His pacing and precision ablation of the atrioventricular (AV) node has been shown. This anatomic approach improved accuracy, limited X-ray exposure, and might allow His pacing in patients with preexisting AV nodal block.     

His bundle pacing in a young child guided by electroanatomical mapping

Pediatric patients with complete congenital atrio‐ventricular (AV) block are generally exposed to life‐long dyssynchronous right ventricular (RV) pacing. His bundle pacing (HBP) is an alternative method of pacing that better restores physiological ventricular activation which could prevent pacing‐induced cardiomyopathy. We present a case of a 5‐year‐old child with complete AV block who underwent successful permanent HBP implantation. Three‐dimensional electro‐anatomical mapping system was used to facilitate the procedure and reduce the fluoroscopy time. There were no acute procedure‐related complications, and electrical parameters were stable at short‐term follow‐up.     

His bundle pacing: Tips and tricks

His bundle (HB) pacing is an established modality for achieving physiological pacing with a low risk of long‐term lead‐related complications. The development of specially designed lead and delivery tools has improved the feasibility and safety of HB pacing (HBP). Knowledge of the anatomy of HB region and the variations is essential for successful implantation. Newer delivery systems have further improved procedural outcomes. Challenging implant cases can be successfully performed by reshaping the current sheaths, using “sheath in sheath” technique or “two‐lead implantation technique.” Special attention to the lead parameters at implant, programming, and follow‐up is necessary for successful long‐term outcomes with HBP. Widespread use of HBP by electrophysiologists and further advances in dedicated delivery systems and leads are essential to further improve the effectiveness of the implantation.     

Electrocardiographic characteristics of distal His bundle pacing in a patient with left bundle branch block

This case demonstrates the feasibility of placing the pacing lead helix at the His bundle distal to the region of left bundle branch block and reveals three types of electrocardiographic characteristics of distal His bundle pacing during correction of left bundle branch block in a patient. As the pacing lead helix was placed distal to the block, left bundle branch block correction was achieved by pacing with a low and stable capture threshold.     

Utility of High‐Output His Pacing during Difficult AV Node Ablation. An Underutilized Strategy

Atrioventricular (AV) node ablation is a commonly performed procedure for patients with chronic drug refractory atrial fibrillation (AF) with episodes of rapid ventricular response. We report on a 72‐year‐old man who had difficulty managing chronic drug refractory AFs with frequent hospitalizations for rapid ventricular rate. The patient was taken to the electrophysiology laboratory for AV node ablation. Extensive mapping and localization techniques of the compact AV node and ablation in the region were unsuccessful. Subsequently, high‐output His bundle pacing using 20 mA at 2 ms of output energy was performed in an attempt to localize the His bundle in areas where high‐output pacing resulted in a narrower QRS complex. Further ablations in the areas where pacing produced a narrower QRS complex resulted in complete heart block. This case highlights the importance of using this simple pacing maneuver to achieve complete heart block in patients in whom standard strategies to localize and ablate the compact AV node are unsuccessful.     

Cardiac resynchronization through selective His bundle pacing in a patient with the so-called InfraHis atrioventricular block

We present a case of infraHis AV block in which selective His bundle pacing with His-ventricular conduction through the conduction system was accomplished. While further investigations are developed, this approach may be an alternative for cardiac resynchronization in cases of difficult coronary sinus access.