右心室流出道电极穿孔1例

患者女,42岁,因病态窦房结综合症,间歇性Ⅲ度房室传导阻滞在我院行双腔起搏器植入术,其中心室主动电极拟同定于右室流出道间隔部.术中右心室电极阻抗1 020 Ω,阈值0.8V,R 波8.0mV,腔内图见ST段抬高10mv.术后患者无特殊不适,心电图提示起搏和感知良好.永久起搏器植入术后17 d,患者因头晕、黑嚎两次入院.     

右心室流出道间隔部起搏的临床观察

目的 比较右心窜流出道间隔部(RVOTS)起搏与右心室心尖部(RVA)起搏对患者心功能的影响.方法 对29例行心脏起搏器植入治疗的Ⅲ°房室传导阻滞患者随机分为RVOTSP组(15例)和RVAP组(14例),观察两组患者手术一般情况,以及术后12个月的心电图、心脏彩超EF值和左心室舒张末期内径等指标变化.结果 两组患者手术时间、心窒电极导线过三尖瓣后的X线曝光时间、术中各项参数的测试结果等比较,差异无统计学意义(P>0.05);术后随访12个月,RVOTSP组QRS波时限、左心窒蕈鼍、NYHA心功能分级和左心室射血分数均优于RVAP组,差异均有统计学意义(P<0.05);术后12个月血浆脑钠肽水平与术前比较,RVOTSP组差异无统计学意义(P>0.05),RVAP组升高(P<0.05).结论 RVOTS起搏较RVA起搏更符合"生理性"起搏的特点,对心功能及心电的不良影响也小于RVA起搏,且安全可靠,能改善患者远期心功能,提高其生存质量.     

斑点追踪技术评价右心室流出道起搏对左心室收缩同步性的影响

目的 应用超声二维斑点追踪技术比较右心室流出道(RVOT)及右心室心尖部(RVA)起搏对左心室收缩同步性的影响。 方法 将60例符合ACC/AHA起搏器植入适应证患者随机分为RVA组和RVOT组,常规将右心房电极置入右心耳处,将右心室电极分别植入RVOT间隔部及RVA。术后1周在保证心室100%起搏下进行二维斑点超声成像分析,记录左心室收缩的纵向、环向及径向应变指标。 结果 RVA组左心室收缩时纵向应变(LS)及环向应变(CS)达峰时间的最大差(TD)分别为(191.07±39.24)ms、(135.92±33.40)ms;RVOT组分别为(129.18±26.20)ms、(69.78±19.10)ms。RVA组LS及CS达峰时间标准差(SD)分别为(62.90±12.63)ms、(52.62±13.58)ms;RVOT组为(41.62±5.71)ms、(28.54±7.96)ms。两组比较,LS及CS达峰时间的TD及SD的差异均有统计学意义(P均<0.001)。RVA组与RVOT组左心室收缩时径向应变(RS)达峰时间的TD分别为(105.43±58.08)ms、(42.00±21.39)ms;SD分别为(41.98±29.48)ms、(17.08±10.46)ms。两组比较,RS的TD及SD的差异均有统计学意义(P均<0.005)。 结论 RVOT起搏时,左心室收缩同步性优于RVA起搏。     

右心室流出道间隔部起搏和右心室心尖部起搏对血流动力学的影响

自上世纪60年代心室单腔起搏器在临床使用,经过数十年的发展,目前起搏器的常规起搏部位仍为右心室心尖部。由于该部位电极导线固定容易而得到广泛应用,但严重的缺点是改变了正常的心室激动顺序。来源于动物与人群的基础研究表明,长期的右心室心尖部(RVA)起搏可以损害左心室收缩     

DDD模式下右心室心尖部起搏与右心室流出道间隔部起搏的临床对比研究

目的 DDD模式下比较右心室心尖部（RVA）起搏与右心室流出道（RVOT）间隔部起搏对患者左心室重构及心功能的影响。方法回顾性分析2009年1月至2012年12月期间我院行永久起搏器（双腔DDD）植入治疗的患者219例,根据心室电极植入部位的不同分为A组（RVA起搏）、B组（RVOT起搏）,每组再根据患者术前左心室射血分数（LVEF）的不同分为两个亚组。调取患者12个月的随访资料,分析两组患者术后LVEF、左心房内径（LAD）、左心室舒张末期内径（LVEDD）及起搏治疗前后各项起搏参数、起搏QRS波群时限和术后并发症等。结果两组在手术成功率、术后并发症等方面的比较无显著差异。术后12个月,A组起搏阈值、电极阻抗较术中均有回落,LVEF较术前降低,LAD、LVEDD较术前增大,差异均有统计学意义（P〈0.05）;B组电极阻抗较术中有回落（P〈0.05）,起搏阈值、R波振幅与术中比较差异无统计学意义,LVEF、LAD、LVEDD与术前相比差异无统计学意义。B组的起搏QRS波群时限较A组显著缩短[（145.09±4.96）ms vs.（157.40±12.44）ms,P〈0.01]。对亚组进行分析发现：术前LVEF≥50%的患者,A、B两组仅LVEDD较术前有增大（P〈0.05）,LVEF和LAD与术前相比差异无统计学意义。术前LVEF〈50%的患者,A组患者的LVEF较术前降低,LAD、LVEDD较术前增大,差异均有统计学意义（P〈0.05）,而B组患者的LVEF、LAD、LVEDD与术前比较差异无统计学意义。结论运用主动固定电极行RVOT起搏在临床应用中是安全、可行的。经过12个月的起搏治疗,对术前心功能不全的患者,RVOT起搏能提供接近生理性的心室激动顺序,维持心室肌电-机械活动同步化,对患者心功能的损害小;对术前心功能正常的患者,虽然RVOT起搏提供了更为协调的心室收缩,但在保护患者左心室收缩功能及阻止左心室重构方面并未显示出优于RVA起搏的证据。     

右心室流出道高位间隔部起搏的应用及护理

目的 探讨主动固定电极行右心室流出道高位间隔部起搏的可行性及护理对策.方法 40例需起搏器植入的患者,采用VVI起搏模式,将其随机分为右心室流出道高位间隔部起搏组（RVOTHS组）和右心室心尖部起搏组（RVA组）各20例,观察两组在术中及术后的各项参数以及护理对策.结果 两组患者均顺利完成手术,两组各1例术后发生电极脱位.全部手术无严重并发症出现.RVOTHS组手术曝光时间明显延长,两组比较差异有统计学意义（t=4.036,P＜0.01）.术中两组患者心室的起搏阈值、感知阈值和电极阻抗比较差异均无统计学意义（P＞0.05）,RVOTHS组起搏心电图QRS波宽度较RVA组变窄,但差异无统计学意义（t=1.613,P＞0.05）.结论 右心室流出道高位间隔部起搏是安全和可行的,术后护理重视心电监测及个性化护理,可使并发症的发生率大大降低.     

右心室心尖部起搏与右心室流出道间隔部起搏对心室高频事件及室性早搏的影响

目的 观察右心室不同起搏比例及不同起搏部位,包括心尖部（RVA）起搏与右心室流出道间隔部（RVOT）起搏对心室高频事件（VHR）和室性早搏（PVC）影响.方法 选取2008年1月至2011年2月因病态窦房结综合征或房室传导阻滞在南京鼓楼医院植入双腔起搏器的患者.依据心室电极植入部位分为RVOT组及RVA组.起搏器植入12个月时进行随访,收集起搏器记录的心律失常数据及心室起搏比例.结果 共入组了96例患者,RVA组及RVOT组各48例.术前两组患者间心功能及24h动态心电图记录的PVC比较无差异.术后12个月随访,依据心室起搏比例,将患者分为三组,VP＜ 10％组、VP 11％～89％组及VP ＞90％组.在RVOT组及RVA组的组内比较结果显示,随着心室起搏比例的增加,VHR及PVC均逐渐减少.组间比较结果,RVA组及RVOT组的VHR无统计学差异（VP＜ 10％组,P=0.2;VP 11％～89％组,P=0.3;VP ＞90％组,P=0.2）,但RVA组的PVC在各起搏比例组的发生均明显高于RVOT组（VP＜ 10％组,P=0.01;VP 11％ ～89％组,P=0.04;VP ＞90％组,P=0.02）,其差异有统计学意义.结论 随着心室起搏比例的增加,PVC及VHR发生率减少,RVA组PVC的发生率高于RVOT组.     

高阻抗电极导线在永久心脏起搏中的应用价值

目的　探讨高阻抗电极在永久心脏起搏中使用的可操作性、安全性及实用意义。方法　 6例患者 ,心房、心室均使用高阻抗电极作为试验组。 2 4例患者使用普通激素电极作为对照组。术中测定心房、心室起搏阈电压和电极阻抗 ,组间进行t检验。术后 1周、1个月和 3个月对高阻抗电极组进行随访 ,测量电极阻抗和起搏阈电压的变化。结果　手术顺利 ,手术时间 (1.8± 0 .5 )小时。两组术中阈电压的差异无统计学意义 (P >0 .0 5 ) ,而电极阻抗有统计学意义差异 (P <0 .0 0 1)。试验组术后随访电极阻抗与阈电压均稳定 ,感知与起搏功能良好 ,无电极脱位、电极断裂、囊袋感染等并发症。结论　相对于普通激素电极 ,高阻抗电极的可操作性变化不大 ,对起搏阈值无不良影响 ,起搏的安全性同普通激素电极相当。高阻抗电极可提高电极阻抗 ,减少输出电流 ,降低能量消耗 ,从而增加起搏器使用寿命     

右心室起搏部位的国内外研究进展

自1958年第一例埋藏式起搏器问世以来,人工心脏起搏经历了50余年的发展,起搏器植入技术已成为治疗缓慢性心律失常最有效的手段。心脏起搏治疗已不仅局限在维持患者的基本心率及患者生存率,更重要的是提高患者生活质量,而这与起搏器激动心肌的顺序、心肌细胞重构程度、心脏电-机械活动的同步性以及血流动力学的稳定性密切相关。在心脏起搏方式、起搏参数一定时,起搏部位的选择是决定临床疗效的重要因素之一。人工心脏起搏器技术经过半个多世纪的发展已取得了长足发展,电生理专家们在积极探索更为接近生理状态的起搏部位。如何提高良好的安全性及可操作性,降低并发症的发生率,提高患者的生活质量,越来越成为当今起搏器发展过程中最需要关注的问题。     

组织多普勒成像评价右心室心尖部与右心室流出道间隔部起搏对心功能的影响

目的运用组织多普勒成像技术（TDI）比较右心室流出道（RVOT）间隔部起搏和右心室心尖部（RVA）起搏对心功能的影响。方法将缓慢心律失常患者65例随机分为RVA起搏组（n=30）、RVOT起搏组（n=35）。于起搏器置入术前、术后1个月、3个月、6个月及12个月分别采用组织多普勒速度-时间曲线测量二尖瓣环舒张早期运动速度（Ea）、收缩期运动速度（Sa）、Tei指数;采用SIMPSON法测量左心室射血分数（LVEF）;采用脉冲多普勒测定二尖瓣口舒张早期最大血流速度（E）,并计算E与Ea比值（E/Ea）。结果 RVA与RVOT两组术前与术后1、3个月的各项指标差异均无统计学意义;术后1、3个月LVEF（61.89±3.37）%vs（61.51±3.11）%,（60.22±4.85）%vs（60.32±4.25）%,Sa（11.38±1.14）cm/s vs（11.44±2.14）,（10.88±1.91）cm/s vs（11.02±1.31）cm/s,E/A 0.96±0.19 vs 0.97±0.23,0.95±0.15 vs 0.96±0.13,E/Ea 8.8±3.6 vs 8.4±4.3,9.1±4.3 vs 8.8±3.2,Tei指数0.48±0.05 vs 0.47±0.08,0.50±0.20 vs 0.47±0.11（均P〉0.05）;术后6个月时RVA起搏组与RVOT起搏组比较,Tei指数及E/Ea增高（0.76±0.26 vs 0.67±0.32,10.9±3.96 vs 9.0±2.8,均P〈0.05）,术后12个月Sa降低,（8.22±1.72）cm/s vs（9.52±2.56）cm/s（P〈0.05）。结论 RVA起搏引起心脏收缩不同步,从而损害左心室收缩和舒张功能。RVOT间隔部可获得较RVA起搏更为优化的心功能参数,是较好的右心室起搏部位。     

右心室流出道起搏电极部位的放射影像及心电图形态的相关性研究

目的 探讨采用主动电极行右心室流出道(RVOT)起搏时,电极部位与其放射影像、心电图形态之间的相关性研究.方法 回顾分析安装体内埋藏式起搏器的110例患者,行RVOT起搏术.行后前位,左前斜45°,右前斜30°放射照片.后前位及左前斜位区分室间隔或游离壁,右前斜位区分流出道上部或下部.术后行12导联心电图.结果 110例患者中有18例电极位于流出道以下,92例(83.6%)位于流出道上部或下部.92例流出道患者中有58例(63.0%)位于间隔部,34例位于游离壁(37.0%);25例(27.2%)位于高位流出道,67例(72.8%)位于低位流出道.间隔部起搏患者与游离壁起搏患者比较,QRS时间短(134±18)ms vs(142±21)ms,P<0.05.游离壁起搏中,Ⅲ导联切迹多见(P<0.01).结论 RVOT起搏的电极X线表现及心电图形态对确定起搏部位有很大的帮助.     

The right ventricular outflow tract: the road to septal pacing

BACKGROUND: Pacing from the right ventricular apex is associated with long-term adverse effects on left ventricular function. This has fuelled interest in alternative pacing sites, especially the septal aspect of the right ventricular outflow tract (RVOT). However, it is a common perception that septal RVOT pacing is difficult to achieve. METHODS AND RESULTS: In this article, we will review the anatomy of the RVOT and discuss the importance of standard radiographic views and the 12-lead electrocardiogram in aiding lead placement. We will also describe a method utilizing a novel stylet shape, whereby a conventional active-fixation, stylet-driven lead can be easily and reliably deployed onto the RVOT septum.     

Characteristics of bifocal pacing: right ventricular apex versus outflow tract. An interim analysis

Bifocal RIGHT ventricular stimulation (BRIGHT) is an ongoing, randomized, single-blind, crossover study of atrial synchronized bi-right ventricular (RV) pacing in patients in New York Heart Association heart failure functional class III, a left ventricular ejection fraction <35%, left bundle branch block and QRS complexes >/=120 ms. This analysis compared the electrical and handling characteristics, and the complications of pacing at the RV apex (Ap) with passive, versus RV outflow tract (OT) with active fixation leads. A mean of 1.6 +/- 0.9 and 2.2 +/- 2.0 attempts were needed to position the Ap and OT leads, respectively (ns). R-wave amplitudes at Ap versus OT were 23 +/- 13 mV versus 14 +/- 8 mV (n = 36, P < 0.001). R-wave amplitudes at the Ap remained stable between implant and M7. R-wave amplitudes at the OT could not be measured after implantation. In two patients, atrioventricular block occurred during active fixation at the OT. Conduction recovered spontaneously within 4 months. Ventricular fibrillation was induced in one patient during manipulation of an Ap lead in the RV. Marked differences were found between leads positioned in the OT versus Ap, partly related to the difference in lead design. Mean R-wave amplitude was higher at the Ap that at the OT. Ease and success rate of lead implant was similar in both positions.     

Right ventricular outflow tract endocardial pacing complicated by intercostal muscle twitching

A recipient of a dual-chamber pacing system, with a bipolar endocardial lead screwed into the right ventricular outflow tract (RVOT), developed intercostal muscle twitching. No lead perforation was identified. This observation suggests that meticulous attention should be paid to this potential complication when choosing the RVOT as a site of permanent endocardial pacing.     

The right ventricular outflow tract: a comparative study of septal, anterior wall, and free wall pacing

BACKGROUND: There is marked heterogeneity in right ventricular outflow tract (RVOT) pacemaker lead placement using conventional leads. As a result, we have sought to identify a reproducible way of placing a ventricular lead onto the RVOT septum. METHODS AND RESULTS: A major determinant is the shape of the stylet used to deliver the active-fixation lead. We compared stylet shapes and configurations in patients who initially had a ventricular lead placed onto the anterior or free wall of the RVOT and then had the lead repositioned onto the septum. All leads were loaded with a stylet fashioned with a distal primary curve to facilitate delivery of the lead to the pulmonary artery, then using a pullback technique the lead was retracted to the RVOT. All lead placements were confirmed by fluoroscopy and electrocardiography. Anterior or free wall placement was achieved by the stylet having either the standard curve or an added distal anterior angulation. In contrast, septal lead positioning was uniformly achieved by a distal posterior angulation of the curved stylet. This difference in tip shape was highly predictive for septal placement (P < 0.001). With septal pacing, a narrower QRS duration was noted, compared to anterior or free wall pacing (136 vs 155 ms, P < 0.001). All pacing parameters were within acceptable limits. CONCLUSION: Using appropriately shaped stylets, pacing leads can now be placed into specific positions within the RVOT and in particular septal pacing can be reliably and reproducibly achieved. This is an important step in the standardization of lead placement in the RVOT.     

频发右心室流出道室性期前收缩对右心室流出道结构影响的研究

目的 探讨右心室流出道(RVOT)起源频发室性期前收缩对RVOT结构的影响.方法 选取2009～2011年行射频消融治疗的频发RVOT起源室性期前收缩患者30例,分析其心电图特征、动态心电图、心脏彩色超声结果及术中精确定位,分析室性期前收缩对RVOT结构的影响.结果 射频消融术前RVOT直径为(31.76±3.33)mm,术后6个月为(30.93±2.68)mm(P＜0.01);相关性分析显示:RVOT直径与室性期前收缩负荷呈正相关(r=0.484,P＜0.05).RVOT间隔部来源室性期前收缩QRS时限为(157.69±18.33) ms,游离壁来源室性期前收缩QRS时限为(179.23±16.05)ms(P＜0.01),QRS时限与来源部位相关(r=0.566,P＜0.01).室性期前收缩QRS时限与RVOT直径无相关性(r=0.097,P＞0.05).结论 RVOT来源室性期前收缩经射频消融治疗后,RVOT直径有减小的趋势,其与室性期前收缩负荷呈正相关,与室性期前收缩形态无相关性.     

右心室流入道间隔部和右心室心尖部起搏神经内分泌激素和心功能的变化

目的探讨右心室流入道间隔部(RVIS)和右心室心尖部(RVA)起搏治疗缓慢性心律失常神经内分泌激素和心功能的变化。方法房室全能型起搏器(DDD)治疗患者106例,男86例,女20例,年龄45～86岁,平均(76.4±9.5)岁,随机分为右心室流入道间隔部起搏组(RVIS起搏组)56例,右心室心尖部起搏组(RVA起搏组)50例。两组心房电极均植入右心耳梳状肌内,RVIS起搏组心室电极植入右心室流入道间隔部、RVA起搏组心室电极植入右心室心尖部。分别观察两组在起搏器植入时、起搏3个月和6个月不同时期,血浆肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)、醛固酮(ALD)、心钠肽(BNP)和去甲肾上腺素(NE)等神经内分泌激素的含量;应用彩色多普勒超声心动图测定:心排血量(CO)、每搏输出量(SV)、射血分数(EF)和左心室舒张末内径(LVDd)。结果 RVA起搏组治疗后,血浆PRA、AngⅡ、ALD、BNP和NE含量增加,而RVIS起搏组则明显下降;RVIS起搏组心功能改善明显:CO、SV和EF值明显增加,LVDd值缩小,RVA起搏组SV、EF值下降,LVDd增加,CO虽然有所增加,但不如RVIS起搏组明显,差异均有统计学意义(P<0.05)。结论 RVIS起搏优于RVA起搏,可明显改善心功能,纠正神经内分泌激素失调,值得临床推广。     

Chronic right ventricular pacing and ventricular function in patients with congenital complete atrioventricular block

Evaluation of: Kim JJ, Friedman RA, Eidem BW et al. Ventricular function and long-term pacing in children with congenital complete atrioventricular block. J. Cardiovasc. Electrophysiol. 18, 373–377 (2007).

Cardiac pacing from right ventricular apex and free wall positions alters inter- and intraventricular impulse conduction and distorts biventricular contractility. In patients with congenital atrioventricular block there is a risk for heart failure, mitral regurgitation, syncope and sudden death before pacemaker implantation, and development of heart failure or mitral regurgitation after long-term ventricular pacing. Recently, selective site pacing has been recommended as a therapeutic option in patients with complete atrioventricular block. The evaluated study demonstrated that left ventricular dysfunction in patients with congenital complete atrioventricular block is rare, even in those who have been paced for more than 10 years. Right ventricular apex pacing and prolonged QRS duration may be associated with decreased ventricular function over time. At this time, with such a low incidence of cardiac dysfunction, right ventricular pacing should be considered an acceptable first-line therapy in this population.