右心室间隔部起搏的血流动力学研究

目的　比较右心室间隔部与右心室心尖部起搏对血流动力学的影响。方法　慢性心房颤动伴长RR间歇或缓慢心室率需植入永久起搏器患者1 0例,均采用抑制型按需心室起搏模式(VVI)。通过超声心动图检查,自身对照研究右室间隔部与右室心尖部起搏的血流动力学差异。结果　术中1 0例患者利用螺旋电极均成功进行了右室间隔部固定,未发生并发症。与术前相比,术中右室心尖部(RVA)起搏时左室射血分数(LVEF)和每搏量(SV)均显著降低( 0 . 56±0. 1 4vs 0 . 6 2±0 .1 4 ,6 7 .72±2 2 . 35mLvs 80 .94±2 2 . 0 4mL ,P <0 . 0 5) ;与术前相比,术中右室间隔部(RVS)起搏时LVEF和SV未显示显著差异;术中RVS起搏的血流动力学参数明显优于RVA起搏(LVEF 0 6 0±0 . 1 3vs 0 . 56±0 . 1 4 ,P <0 .0 5;SV 76 . 97±1 7. 2 3mLvs 6 7 .72±2 2 . 35mL ,P <0. 0 5)。结论　与术前相比,RVA起搏恶化血流动力学,RVS起搏对血流动力学无明显不良影响。RVS起搏通过最大限度地保持正常心室激动顺序和双心室收缩的同步性,实现较为良好的血流动力学状态。     

主动固定螺旋电极在右室流出道间隔部起搏中的应用体会

目的探索采用主动固定螺旋电极行右室间隔部起搏的临床可行性。方法随机选择54例需要安装双腔起搏器的患者行右室流出道间隔部起搏,将心室起搏螺旋电极先后定位于右室心尖部及右室流出道间隔部并测试起搏参数。结果右室流出道间隔部电极定位成功率为98.15%,该部位起搏参数满足起搏要求,同时起搏的QRS波时限较心尖部变窄(130.45±18.24msvs153.11±20.10ms,P<0.001)。结论采用主动固定螺旋电极行右室流出道间隔部起搏安全性高、可行性好。     

右心室间隔部起搏的核素心室显像位相分析及心电图研究

目的 :观察右心室间隔部 (RVS)起搏时的心室激动顺序和双心室同步性 ;评估在接受心室起搏的患者中心电图的演变。　　方法 :慢性心房颤动伴长RR间歇或缓慢心室率需植入永久起搏器患者 10例 ,男性 7例 ,女性 3例 ,平均年龄(64 2 0± 12 61)岁 ,均采用抑制型按需心室起搏 (VVI)模式先后顺序进行右心室心尖部 (RVA)和RVS。记录术前心电图、术中RVA和RVS起搏心电图 ;术后进行核素心室显像位相分析 ,对比自身心律与RVA和RVS起搏时心室激动顺序和双心室同步性的差异。　　结果 :核素心室显像位相分析证实RVA起搏造成心室激动顺序异常和双心室失同步 ;RVS起搏时心室激动顺序、双心室同步性与正常基本一致。RVA起搏时QRS波群较术前自身增宽 [(173 0 0± 14 94)msvs (74 5 0± 7 62 )ms ,P <0 0 0 1] ,差异有非常显著性 ;RVS起搏的QRS波群宽度较RVA起搏缩窄 [(13 6 0 0± 13 5 0 )msvs (173 0 0± 14 94)ms ,P <0 0 0 1) ] ,差异有非常显著性。　　结论 :RVS起搏时心室激动顺序、双心室同步性与正常基本一致 ;与RVA起搏相比RVS起搏时心电轴、QRS波群与正常心电图相似或接近。     

采用螺旋电极导线行右室流出道间隔部起搏的经验

目的介绍主动固定螺旋电极在右室流出道间隔部起搏中的应用经验。方法86例起搏适应证患者随机分成两组,一组42例采用主动固定螺旋电极行右室流出道室间隔起搏(简称主动电极组),另一组44例应用被动固定电极行右室心尖起搏(简称被动电极组),观察两组有关手术指标及主动电极组的起搏参数。结果主动电极组电极操作时间长于被动电极组(18.4±7.7 min vs 16.6±6.5 min,P<0.05),起搏QRS波时限则明显短于被动电极组(0.138±0.046 s vs 0.162±0.020 s,P<0.01);主动固定螺旋电极植入后起搏阈值达高峰,15 min后即降至稳定水平(0.78±0.26 Vvs 0.54±0.27 V,P<0.05);主动电极组1例发生电极脱位。结论主动固定螺旋电极在右室流出道室间隔起搏中是可行的、安全的,植入方法是关键。     

右室中位间隔起搏的可行性与安全性

目的评价中位右室间隔起搏(RVSP)方法的可行性和安全性。方法选择101例行RVSP,右室心尖部起搏(RVAP)126例作对照。在X线指导下将室间隔分四区,分别为His束区、右室流出道间隔区、低位前间隔区和右室流入道间隔区,精确定位RVSP的主动导线在中位间隔位置。记录术中曝光时间、电极导线植入参数、心电图和术后第3,6,12个月随访资料。结果两组手术曝光时间无差异。RVSP组起搏前后的QRS波形态有稳定的特征性变化,可结合X线用于指导导线定位。RVSP组起搏后的QRS波时限明显小于RVAP组(98.19±22.30 msvs 120.80±24.14 ms,P<0.01),术中两组的心室导线的起搏阈值、电流、阻抗均存在明显差异(0.76±0.30 V vs0.39±0.10 V,0.98±0.52 mA vs 0.36±0.19 mA,690.67±141.64Ωvs 867.16±201.23Ω,P<0.01)。在随访中两组心室起搏阈值和阻抗较稳定。结论在X线指导下将室间隔分区,主动导线能精确、快捷地固定于右室中位间隔部。该部位是较理想的起搏部位,安全可行。     

主动固定电极导线行右室间隔部生理性起搏的临床技术研究

右室心尖部起搏是目前最常用的永久起搏方式，但非生理性起搏方式。右室间隔部起搏可以实现近希氏束起搏，从而获得接近生理状态的心室激动顺序和双心室同步，这是一种近似生理性的起搏方式，但是需要借助主动固定电极导线，且其临床操作有一定难度。笔者探索临床应用主动固定电极导线行右室间隔部（包括流出道间隔部和流入道间隔部）起搏的操作技术和安全性。     

动脉硬化疾病患者右室流出道起搏的探讨

目的探讨动脉硬化疾病患者适宜的起搏部位。方法7例(冠心病3例、高血压4例)置入翼状电极至右室心尖部后起搏及感知功能障碍的患者,重置螺旋电极至右室流出道,观察其前后的起搏及感知功能。结果7例右室流出道起搏的起搏阈值较右室心尖部起搏显著降低,感知阈值较右室心尖部显著升高(0.5±0.2Vvs8.7±1.6V,10.6±3.6mVvs2.7±0.8mV,P<0.01),阻抗无明显差异。随访16±6个月,无电极脱位,起搏感知功能良好。结论右室流出道可作为有动脉硬化病史患者的起搏部位。     

右室间隔部起搏对心功能影响的Meta分析

目的系统评价右室间隔部（RVS）起搏对心功能的影响。方法计算机检索Cochrane图书馆（2010年第1期）、PubMed、EMbase,同时检索CBM、CNKI、VIP和万方数据库,检索时间截至2010年3月,收集右室间隔部（RVS）起搏对比右室心尖部（RVA）起搏对心功能影响的随机对照试验（RCT）,并按Cochrane协作网推荐的方法进行质量评价、资料提取和Meta分析。结果共纳入35个RCT,包括2034例患者。Meta分析结果显示：①左室射血分数：RVS起搏在3个月和18个月的左室射血分数均高于RVA起搏,差异有统计学意义[WMD=3.53,95%CI：1.02～6.04];[WMD=7.44,95%CI：5.46～9.42]。②QRS波时限：RVS起搏在术后即时和3个月的QRS波时限均小于RVA起搏,差异有统计学意义[WMD=-27.7,95%CI：-34.24～-21.15];[WMD=-17.02,95%CI：-24.14～-9.90]。③起搏参数：术后3个月时RVS起搏的起搏阈值与RVA起搏无差别。RVS起搏的感知阈值和阻抗均低于RVA起搏。结论右室间隔部起搏能给患者带来良好的近生理状态的双心室电传导,并改善患者的血流动力学,右室间隔部有望成为首选的心室起搏部位。     

小儿右室流出道起搏

对于一些需要安装永久起搏器的患者来讲,由于易于固定,起搏阈值低等优点,右心室起搏常将起搏电极置于心尖部,但长期随访发现,心尖部起搏可改变心室激动顺序,导致心室收缩不同步,造成二尖瓣反流、心房颤动和心功能不全。研究发现右室流出道起搏对左室功能的保护较右室心尖部起搏有利,由于右室流出道起搏靠近His束,电活动近似正常生理状态,可使左右心室电-机械活动更协调,从而抑制心室重构并保护心功能,因此,右室流出道起搏是替代右室心尖部起搏的较好选择。     

关于右心室间隔部起搏的双心室电同步性和血流动力学探讨

目的以右心室心尖部起搏为参照,评估右心室间隔部起搏的双心室电同步性和血流动力学效应。方法20例患者植入全自动双腔(DDD型)起搏器,随机分组,一组10例行间隔部起搏(RVS组),一组行心尖部起搏(RVA组);分析两组有效起搏及1、3个月随访时各起搏参数差异;对比术中心室电极到位所需X线曝光时间、术中及术后并发症;比较术前自身心律心电图、术后起搏心电图的QRS波宽度、形态;比较两组术前和术后6个月随访的左心室射血分数(LVEF)、二尖瓣血流E峰和A峰最大充盈速度比值(E/A)差异。结果RVS组和RVA组起搏电压阈值、电极阻抗、R波高度无明显差异(P>0.05)。电极植入后第1、3个月随访,两组起搏参数之间无明显差异,且动态变化相似;心室电极到位所需X线曝光时间:RVA组为(203.0±127.3)s,RVS组为(581.0±124.7)s(P<0.05)。电极植入术中及术后均未出现并发症;术前和术后心电图Ⅱ导联QRS宽度:RVA组分别为(0.11±0.03)s、(0.19±0.02)s(P<0.05);RVS组分别为(0.10±0.02)s、(0.12±0.02)s(P<0.05),术后QRS形态与术前心电图相似。间隔部起搏和心尖部起搏心电图的QRS波宽度对比,前者明显窄于后者(P<0.01)。术前2组LVEF、E/A比值无明显差异。与术前相比,RVA组6个月随访的LVEF、E/A均明显降低(P<0.05),RVS组无明显变化(P>0.05)。6个月随访RVS组LVEF、E/A均明显高于RVA组(P<0.05)。结论右心室间隔部起搏是安全、有效的,比右心室心尖部起搏更有利于双心室电激动的同步性,且不会给心功能带来明显不良影响。     

右室流出道起搏现状

右室心尖部作为传统的永久心脏起搏器植入位点,主要是因为电极容易放置及电极脱位率低。但是心尖部起搏属非生理性起搏,它使心室除极和机械收缩发生异常,从而导致长期的血流动力学紊乱(心室收缩和舒张异常)和组织结构的改变。随着近年主动固定的螺旋电极及螺旋电极操作手柄的问世,使右室流出道起搏成为可能。大量动物实验和临床研究提示右室流出道靠近房室结、希氏束部位,在此部位起搏心室激动和收缩顺序趋于正常,从而能明显的改善血流动力学指标。目前右室流出道起搏尚处于临床实验阶段,且关于右室流出道解剖位点的确定,适宜患者群的筛选标准、监测和评价指标的选择尚无统一的标准。其长期效果及能否改善患者预后等还有待更深入的研究。现就目前国内外关于右室流出道起搏的研究现状综述如下。     

右心室心尖部起搏和右心室间隔部起搏对起搏参数和心电图的影响

目的评估右室间隔部起搏和右室心尖部起搏对起搏参数和双心室电同步性的影响。方法将20例植入DDD型起搏器患者随机为分2组（每组10例）:一组患者行间隔部起搏,一组行心尖部起搏;分析两组有效起搏时及1、3个月随访时各起搏参数差异;对比术中心室电极到位所需X射线曝光时间、术中及术后并发症;比较术前自身心律心电图、术后起博心电图的QRS波宽度、形态。结果有效起搏时心尖部和间隔部起搏电压阈值、电极阻抗、R波高度无显著差异。电极植入后第1、3个月随访,两组起搏参数之间无显著差异,且动态变化相似;心室电极到位所需X线曝光时间:心尖部为（203±127）s,间隔部为（581±124）s（P<0.01）。电极植入术中及术后均未出现并发症;术前和术后心电图Ⅱ导联QRS宽度:心尖部起搏组分别为（0.11±0.03）s、（0.19±0.02）s（P<0.05）;间隔部起搏组分别为（0.10±0.02）s、（0.12±0.02）s,术后QRS形态与术前心电图相似。术后间隔部起搏和心尖部起搏心电图的QRS波宽度对比,前者明显窄于后者（P<0.01）。结论右心室间隔部起搏和右心室心尖部起搏同样安全、有效,而且更符合生理性心室激动顺序,有利于双心室电激动的同步性。     

Novel electrophysiologic parameter of dispersion of atrial repolarization: comparison of different atrial pacing methods

INTRODUCTION: Heterogeneity of ventricular repolarization plays a major role in reentrant tachyarrhythmias in cardiac tissue. However, the role of atrial repolarization added activation time (AT) to refractoriness in atrial vulnerability has not been investigated in detail. METHODS AND RESULTS: The study population consisted of 34 patients: 18 with atrial fibrillation (AF) and 16 without AF (control group). The effective refractory periods (ERPs) in the right atrial appendage, low lateral right atrium, high right septum, and distal coronary sinus, and ATs from P wave onset to each electrogram during sinus rhythm and right atrial appendage, low lateral right atrial, high right septal, distal coronary sinus, and biatrial pacing were measured. Atrial recovery time, defined as the sum of AT and ERP, and its dispersions during sinus rhythm, right atrial appendage, low lateral right atrial, high right septal, distal coronary sinus, and biatrial pacing were calculated. Both ERP dispersion and atrial recovery time dispersion during sinus rhythm were significantly greater in the AF group than in the control group. Atrial recovery time dispersion during distal coronary sinus, high right septal, or biatrial pacing was significantly smaller than that during right atrial appendage or low lateral right atrial pacing in each group. In particular, atrial recovery time dispersion during distal coronary sinus pacing was the smallest of the five pacing methods in the AF group. P wave duration during biatrial or high right septal pacing was significantly shorter than during right atrial appendage, low lateral right atrial, or distal coronary sinus pacing in each group. CONCLUSION: Atrial recovery time dispersion is suitable as an electrophysiologic parameter of atrial vulnerability. Distal coronary sinus pacing may prevent AF by increasing homogeneity of atrial repolarization, whereas biatrial and high right septal pacing contribute not only homogeneity of atrial repolarization but also improvement of atrial depolarization.     

右室中间隔起搏患者长期预后的研究

背景长期心尖部起搏患者血流动力学和临床疗效差。目的评价右室中位间隔部与心尖部起搏对患者预后的影响。方法：将入选患者分为右心室心尖部组（RVAP组）和右室中位间隔部组（RVSP组）,经过长期随访后比较两组患者术后全因死亡率、新发心衰和新发房颤发生率。结果：经过46.9±9.6个月随访,RVSP组与RVAP组全因死亡率差异无统计学意义（p〉0.05）。与RVAP组比较,RVSP组新发心衰和新发房颤显著下降（p〈0.05）。多因素回归分析表明,RVAP新发心衰的独立危险因素。结论：RVSP患者长期预后较好,可作为RVAP的替代起搏位点。     

右心室心脏起搏升级双心室起搏的临床应用进展

心脏再同步化治疗是一项成熟应用于临床进展期心力衰竭合并左心收缩功能不全,心脏失同步患者治疗方法。右心室心尖部起搏改变了正常心脏的激动收缩顺序从而导致心脏电机械失同步,心脏收缩功能下降最终发生心力衰竭。适时地将起搏患者右心室起搏系统升级为双心室起搏可以纠正右室起搏导致的心脏失同步,最大限度保持左、右双心室间正常的电激动顺序和收缩同步性,有效地避免了起搏对血流动力学和心功能的不良影响。近来短期研究发现这种起搏系统升级可明显改善心脏活动的同步性,从而改善心功能、提高生活质量。文章综述了右室心尖部起搏的病理生理及升级右室起搏到双室起搏治疗的相关临床试验、显效机制及存在的问题。     

Dual Site Right Atrial Pacing in the Prevention of Symptomatic Atrial Fibrillation Refractory to Drug Therapy and Unrelated to Sinus Bradycardia

Dual-site right atrial pacing has been shown recently to prevent atrial fibrillation relapses in patients affected by drug-refractory, highly-recurring tachyarrhythmia, associated to sinus bradycardia. The aim of our study was to verify whether this stimulation modality could be useful in patients affected by refractory atrial fibrillation unassociated to sinus bradycardia. Methods and Results: Fifteen patients (6 males) affected by refractory, symptomatic atrial fibrillation, and potential candidates to AV node ablation, were prospectively enrolled. Mean age was 65±5 years (range 62–78). Associated pathology was arterial hypertension in 12, and dilated cardiomyopathy in 3. Eight patients were affected by persistent atrial fibrillation, and seven by paroxysmal atrial fibrillation. The duration of the arrhythmia was 61±63 months (range 3–216). Left atrial diameter was 39.4±4.2 mm (range 33–46), left ventricular end-diastolic diameter was 52.4±12.2 mm (range 41–90), and left ventricular ejection fraction was 55±16 (range 18–81). Single chamber atrial pacing was used in 10 patients, dual chamber in 5 patients.The mean duration of follow up was 24±12 months (range 3–41). During this period the number of episodes of atrial fibrillation decreased from a mean of 13±38 (range 1–1 ± ) to 0.4±0.7 (range 0–2.3) per month (p < 0.001). In the subgroup of patients with persistent atrial fibrillation the number of episodes decreased from a mean of 20.4±52.4 (range 1–1 ± ) to 0.6±0.9 (range 0–2.3) (p < 0.001). In patients with paroxysmal atrial fibrillation the number of episodes decreased from 4.6±3.5 (range 2–12) to 0.2±0.5 (range 0–1.4) (p < 0.001). One patient (6.7%) developed chronic atrial fibrillation 16 months after the implant, 2 remaining patients (13%) had their arrhythmia unaltered. After the implant the number of Class 1 antiarrhythmic drugs fell from 18 to 6 (p < 0.001) and that of Class 2 changed from 0 to 7 (p < 0.001). The use of Class 3 and 4 did not change significantly. No complications related to implant were observed. Conclusions: Permanent dual-site right atrial pacing can prevent atrial fibrillation recurrences in patients affected by highly symptomatic episodes unassociated to sinus bradycardia.     

右室双部位起搏的临床应用

右室双部位起搏是一种阃接的双室起搏技术，操作简单，不增加安置术的风险，同时可以使心室再同步变为可能，增加心肌收缩力，改善心功能，具有较好的临床应用价值。     

低位房间隔起搏与右心耳起搏的临床对比研究

目的 探讨低位房间隔起搏与右心耳起搏在植入操作时间、起搏参数方面的差异.方法 选取40例因窦房结功能障碍或成人获得性房室传导阻滞导致的缓慢型心律失常行起搏治疗的患者分为两组.其中,房间隔组20例,采用主动固定螺旋电极行低位房间隔起搏;右心耳组20例,采用被动固定翼状电极行右心耳起搏.对比两组电极植入操作时间,电极植入时、术后1个月、3个月的起搏参数（阈值和阻抗）.结果 房间隔组与右心耳组比较,心房电极植入操作时间和起搏参数在术中、术后1个月、3个月差异均无统计学意义（P＞0.05）.结论 低位房间隔起搏与右心耳起搏具有相似的电极植入操作时间以及相同的起搏参数,为临床起搏治疗的有效部位.     

Differences in pacing from the atrial appendage and the lateral atrial free wall on left ventricular filling and haemodynamics during DDD pacing.

INTRODUCTION: Atrioventricular sequential pacing involves stimulation from electrodes in the right atrium, generally the atrial appendage (RAA) and the right ventricular apex. The appendage, however, may be unsuitable if a stable position cannot be achieved. The aim of this study was to assess the haemodynamic consequences of different atrial stimulation sites during DDD pacing. METHODS: In 12 consecutive patients (mean age 67 +/- 7 years) who underwent DDD pacemaker implantation, an additional temporary bipolar pacing electrode was positioned on the right atrial free wall. Pacing was performed alternating from the two locations at 85, 100 and 120 beats per minute (bpm). Paced atrioventricular delay was set at 180 ms. Cardiac output and mitral inflow measurements were performed using Doppler echocardiography. RESULTS: Pacing at 85 and 100 bpm resulted in a significantly higher A-peak velocity from the RAA compared with the right atrial free wall. Cardiac index was consistently higher from the RAA location (2.4 +/- 1.2 vs 2.1 +/- 0.91. min-1 m-2 at 85 bpm, 2.71 +/- 1.4 vs 2.35 +/- 1.11. min-1 m-2 at 100 bpm and 2.94 +/- 1.5 vs 2.61 +/- 1.41. min-1 m-2 at 120 bpm, P < 0.05). CONCLUSION: Stimulation from the RAA was superior to stimulation from the right atrial free wall with respect to left ventricular filling and cardiac output. Compared with stimulation from the right atrial free wall, RAA pacing resulted in an increase of 10-15% in cardiac output.