DDD起搏器选择心室起搏部位对血流动力学的影响

目的比较右室间隔部(RVS)和右室心尖部(RVA)起搏对血流动力学的影响。方法42例置入DDD起搏器的患者,分为RVS组和RVA组;比较2组术前和术后3个月随访的左室射血分数(LVEF)、心脏指数(CI)、每搏量(SV)、左室最大压力上升速率(dp/dtmax)、左室最大压力下降速率(-dp/dtmax)、二尖瓣血流E峰和A峰最大充盈速度比值(E/A)、等容舒张时间(IVRT)差异。结果与术前相比,RVA组3个月随访的LVEF、CI、SV、dp/dtmax、-dp/dtmax、E/A、IVRT均显著降低(0.51±0.04vs0.54±0.03;2.33±0.09L/min.m-2vs2.68±0.11L/min.m-2;71.11±14.2mlvs80.17±16.12ml;1614±133mmHg/svs1702±155mmHg/s;2230±234mm-Hg/svs2404±242mmHg/s;1.38±0.47vs1.86±0.28;73.2±3.86msvs77.6±4.15ms,均P<0.05),RVS组无明显变化。3个月随访RVS组LVEF、CISV、SV、dp/dtmax均显著高于RVA组(P<0.05)。结论RVS起搏对血流动力学无不良影响。     

右室双部位起搏与双室同步起搏的急性血液动力学对比研究

比较右室双部位 (RV Bi)起搏和双室 (BiV)同步起搏对血液动力学的影响 ,并与右室心尖部 (RVA)、右室流出道 (RVOT)、左室基底部 (LVB)起搏相比较 ,明确双部位起搏是否优于单部位起搏。 15例患者中病窦综合征 8例、Ⅲ度房室阻滞 7例。分别行RVA、RVOT、LVB、RV Bi、BiV起搏 (VVI,6 0～ 90次 /分 ) ,测定心输出量 (CO)和心脏指数(CI)、肺毛细血管嵌顿压 (PCWP)和QRS波时限 (QRSd)。结果 :①与RVA起搏相比 ,RVOT、LVB、RV Bi、BiV起搏CI分别增加了 7.5 %、11.3%、15 .5 %和 17.2 % ,PCWP分别降低了 14.9%、10 .3%、2 1.7%和 2 0 .0 % (P均 <0 .0 1)。②RV Bi、BiV起搏较RVOT、LVB起搏的CO、CI增高而PCWP降低 (P均 <0 .0 5 )。③RV Bi与BiV起搏、RVOT与LVB起搏之间CO、CI和PCWP无显著差异。④RVOT、RV Bi、BiV起搏的QRSd(分别为 12 8± 11,111± 16 ,10 3± 13ms)较RVA起搏 (146± 18ms)时显著缩短 (P≤ 0 .0 0 1) ,而LVB起搏 (142± 15ms)与RVOT、RVA起搏时无显著差异。结论 :RV Bi起搏和BiV同步起搏的急性血液动力学效果无明显差异 ,但双部位起搏的效果明显优于单部位起搏 ;双部位起搏的QRSd也比单部位起搏明显缩短     

右心室流出道间隔部起搏与心尖部起搏的血流动力学对比研究

目的比较右心室流出道间隔部(RVOTS)与右心室心尖部(RVA)起搏对血流动力学的影响,评价RVOTS起搏的可行性。方法 53例需植入永久起搏器患者,均采用抑制型按需心室起搏模式(VVI),其中RVA起搏28例,RVOTS 25例。随访3～10个月,采用超声心动图检查方法检测血流动力学参数,包括LVEF、左室内径缩短分数(FS)、心输出量(CO)、心脏指数(CI),研究RVOTS与RVA起搏的术前、术后血流动力学差异。结果所有患者心室起搏保证在80%以上,与手术前比较,RVOTS起搏时,LVEF、FS、CO、CI分别下降了3.46%±3.89%、1.20%±2.47%、(0.19±1.32)L/min、(0.09±0.52)L·min~(-1)·m~(-2),差异无统计学意义(均为P>0.5)。与手术前比较,RVA起搏时LVEF、FS、CO、CI分别下降了14.27%±5.83%、8.10%±3.79%、(1.56±1.11)L/min、(1.13±0.52)L·min~(-1)·m~(-2)(均为P<0.01),RVOTS起搏与RVA起搏相比LVEF、Fs、CO、CI明显改善(均为P<0.05),且临床症状明显减轻。结论 RVOTS起搏对血流动力学无明显不良影响。     

右心室双部位起搏治疗心力衰竭的疗效和安全性

目的评价右心室双部位(RV-Bi)起搏治疗慢性充血性心力衰竭的疗效。方法 3例心肌病合并心力衰竭患者和3例起搏器综合征患者接受了RV-Bi起搏治疗。比较术前及术后3个月,在RV-Bi起搏、右心室心尖部(RVA)起搏和右心室流出道(RVOT)起搏模式下,患者QRS宽度(QRSd)、QRS电轴(QRSa)和心功能的变化。结果 RV-Bi起搏与RVOT起搏比较,QRSa差异无统计学意义,但与RVA起搏比较,QRSa的差异具有统计学意义;RV-Bi起搏的平均QRSd(143ms)最窄,较RVA起搏(177ms)缩短34ms,较RVOT起搏(155ms)缩短12ms。RV-Bi起搏时心功能优于RVA和RVOT起搏。RV-Bi起博时射血分数(50.4%±3.6%)、每搏量[(65±14)ml]和心输出量[(5.77±0.69)L/min]均较术前射血分数(38.5%±6.2%)、每搏量[(50±18)ml]、心输出量[(4.16±0.55)L/min]及RVA起搏射血分数(34.2%±7.4%)、每搏量[(48±15)ml]、心输出量[(4.12±0.51)L/min]和RVOT起搏时射血分数(45.4%±5.6%)、每搏量[(62±16)ml]、心输出量(5.42±0.63 L/min)显著提高(均为P<0.05)。结论 RV-Bi起搏可改善心室的激动顺序和同步性,可用于慢性心力衰竭和起搏器综合征的治疗,此项技术可作为双室同步起搏技术的替代选择,并具有手术简便和价格低廉的优点。     

右室流出道间隔部和心尖部起搏对心功能和重构的影响

目的比较右室流出道(RVOT)和右室心尖部(RVA)起搏对心脏做功和重构的影响。方法 83例缓慢心律失常的患者,其中男40例,女43例,随机分为RVOT间隔部起搏组(RVOT组,n=42)和RVA部起搏组(RVA组,n=41),观察两组QRS波时限、新出现心房颤动(简称房颤)的情况、心腔内径及左室射血分数(LVEF)的变化。结果随访11.47±1.67个月,两组术后QRS波时限均较术前明显延长(P<0.01),RVA组明显长于RVOT组(P<0.01);两组的左房内径和左室收缩末径均未见明显变化,RVA组1年后左室舒张末径较术前显著增加(53.53±5.72 mm vs 50.03±6.20 mm,P<0.05),两组1年后LVEF均较术前显著降低(RVOT、RVA比较分别为0.57±0.10 vs 0.62±0.11,0.53±0.08 vs 0.63±0.10,P均<0.01);两组新出现房颤例数亦未见差异。结论 RVOT起搏对心室重构的影响要好于RVA起搏。     

右室双部位起搏的急性血流动力学研究

目的 :比较右室双部位 (RV Bi)起搏与右室心尖部 (RVA)、右室流出道 (RVOT)起搏对急性血流动力学的影响。方法 :对 15例患者 (其中病态窦房结综合征 8例 ;三度房室传导阻滞 7例 )。分别行RVA、RVOT、RV Bi起搏 (VVI ,6 0～ 90次 /min) ,测定心排血量 (CO)和心排血指数 (CI)、平均肺动脉压 (mPAP)和肺毛细血管嵌顿压 (PCWP) ,QRS宽度 (QRSd)和电轴 (QRSa)。结果 :RV Bi起搏较RVOT、RVA起搏CO、CI明显增加 ,均P<0 .0 1;PCWP显著降低 ,为P <0 .0 5～ 0 .0 1;3个不同部位起搏mPAP无明显变化 ;RV Bi起搏较RVOT起搏的QRS波时限平均缩短 17ms,较RVA平均缩短了 35ms ,均P <0 .0 1。结论 :RV Bi起搏的急性血流动力学效果明显优于RVOT ,RVA等单部位起搏。     

右心室流出道间隔部起搏对左心室功能的影响

目的比较右心室流出道间隔部(RVOT)起搏与右心室心尖部(RVA)起搏的血流动力学差异;评估RVOT起搏技术的可行性与安全性。方法选择有永久起搏器置入适应证的患者75例。根据术者建议和患者意愿分为RVOT组(40例)和RVA组(35例)。所有房室传导阻滞及病窦综合征合并一度房室传导阻滞患者采用双腔起搏双腔感知触发抑制型起搏模式,心房颤动伴长间歇患者采用抑制型心室按需起搏模式。比较2组的血流动力学差异。结果 RVOT组的QRS波宽度较RVA组缩窄(23.2±28.7)ms,差异有统计学意义(P<0.01)。与RVA组比较,RVOT组LVEF、左心室短轴缩短率明显升高,左心室舒张末容积明显下降(P<0.05,P<0.01)。与术前比较,RVA组LVEF、左心室短轴缩短率明显下降,左心室舒张末容积明显升高,差异有统计学意义(P<0.01)。结论利用螺旋电极进行RVOT起搏可行且较为安全。RVOT起搏的血流动力学参数优于RVA。     

心脏选择性部位起搏的电和机械同步性研究的初步报告

目的观察心脏不同部位起搏时的电及机械同步性和血流动力学变化。方法14例患者分别于右室心尖（RVA）、希氏束部位（His）、右室高位流出道间隔部（RVOT）起搏,记录心输出量和心脏指数;比较不同部位起搏和自身心律时12导联体表心电图的QRS波宽度和方向,以评价电同步性;用全数字化超声诊断系统的向量速度显像评价机械同步性。结果心输出量和心脏指数在RVA起搏时较差,但差异无统计学意义（P〉0．05）。各部位起搏时QRS波的宽度：His为（124±5．3）ms,RVOT（144±7．1）ms,RVA（156±8．6）ms,均较自身心律（92±4．5）ms时宽（P〈0．01）;而His及RVOT均较RVA起搏时的QRS波时限窄,其差异有统计学意义（P〈0．01）。向量速度显像检查提示,RVOT起搏相对于RVA起搏有更好的机械同步性。结论RVOT可能较传统的RVA部位起搏好,同时手术操作容易。     

DDD房室顺序起搏对慢性心力衰竭左室重构的逆转效应

目的　评价右房 -右室间隔上部顺序 DDD起搏 (RA- URIS)对慢性心力衰竭患者左室重构的逆转效应。方法　 37例病态窦房结综合征或房室传导阻滞伴心力衰竭的患者随机分为 RA- URIS组 (1 8例 )和右房 -右室心尖起搏治疗 (RA- RVA)组 (1 9例 ) ,比较术前和术后 1 2个月的左室舒张期末径、左室心肌重量指数、左室射血分数、6min步行距离测试和生活质量评分。结果　 RA- URIS组 1年后左室心肌重量指数 (1 0 2 .5± 1 6.3g/m2 )较术前 (1 1 0 .1± 1 8.5g/m2 )明显下降 (P<0 .0 5) ,左室射血分数 (38.3%± 1 0 .1 % )较术前 (30 .7%± 8.4% )明显提高 (P<0 .0 5) ;而 RA- RVA组上述指标较术前无明显变化。RA- URIS组术后 1年较 RA- RVA组左室心肌重量指数明显下降 (P<0 .0 5) ,左室射血分数 (33.7%± 5.5% )明显提高 (P<0 .0 5)。 RA- URIS组术后 1年 6 min步行距离测试明显提高 (386± 69m,330± 78m,P<0 .0 5) ,生活质量评分较术前明显下降 (2 3± 2 0 ,40±2 5,P<0 .0 1 ) ,而 RA- RVA组则没有明显变化。结论　 RA- URIS顺序起搏能逆转慢性心力衰竭患者的左室重构 ,改善生活质量。     

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。     

Functional abnormalities in patients with permanent right ventricular pacing: the effect of sites of electrical stimulation

OBJECTIVES: We sought to evaluate the long-term effects of alternative right ventricular pacing sites on myocardial function and perfusion. BACKGROUND: Previous studies have demonstrated that asynchronous ventricular activation due to right ventricular apical (RVA) pacing alters regional myocardial perfusion and functions. METHODS: We randomized 24 patients with complete atrioventricular block to undergo permanent ventricular stimulation either at the RVA (n = 12) or right ventricular outflow (RVOT) (n = 12). All patients underwent dipyridamole thallium myocardial scintigraphy and radionuclide ventriculography at 6 and 18 months after pacemaker implantation. RESULTS: After pacing, the mean QRS duration was significantly longer during RVA pacing than during RVOT pacing (151 +/- 6 vs. 134 +/- 4 ms, p = 0.03). At six months, the incidence of myocardial perfusion defects (50% vs. 25%) and regional wall motion abnormalities (42% vs. 25%) and the left ventricular ejection fraction (LVEF) (55 +/- 3% vs. 55 +/- 1%) were similar during RVA pacing and RVOT pacing (p > 0.05). However, at 18 months, the incidence of myocardial perfusion defects (83% vs. 33%) and regional wall motion abnormalities (75% vs. 33%) were higher and LVEF (47 +/- 3 vs. 56 +/- 1%) was lower during RVA pacing than during RVOT pacing (all p < 0.05). Patients with RVA pacing had a significant increase in the incidence of myocardial perfusion defects (p < 0.05) and a decrease in LVEF (p < 0.01) between 6 and 18 months, but patients with RVOT pacing did not (p > 0.05). CONCLUSIONS: This study demonstrates that preserved synchronous ventricular activation with RVOT pacing prevents the long-term deleterious effects of RVA pacing on myocardial perfusion and function in patients implanted with a permanent pacemaker.     

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。     

Long‐Term Mechanical Consequences of Permanent Right Ventricular Pacing: Effect of Pacing Site

Optimal Right Ventricular Pacing Introduction: Long‐term right ventricular apical (RVA) pacing has been associated with adverse effects on left ventricular systolic function; however, the comparative effects of right ventricular outflow tract (RVOT) pacing are unknown. Our aim was therefore to examine the long‐term effects of septal RVOT versus RVA pacing on left ventricular and atrial structure and function. Methods: Fifty‐eight patients who were prospectively randomized to long‐term pacing either from the right ventricular apex or RVOT septum were studied echocardiographically. Left ventricular (LV) and atrial (LA) volumes were measured. LV 2D strain and tissue velocity images were analyzed to measure 18‐segment time‐to‐peak longitudinal systolic strain and 12‐segment time‐to‐peak systolic tissue velocity. Intra‐LV synchrony was assessed by their respective standard deviations. Interventricular mechanical delay was measured as the difference in time‐to‐onset of systolic flow in the RVOT and LV outflow tract. Septal A’ was measured using tissue velocity images. Results: Following 29 ± 10 months pacing, there was a significant difference in LV ejection fraction (P < 0.001), LV end‐systolic volume (P = 0.007), and LA volume (P = 0.02) favoring the RVOT‐paced group over the RVA‐paced patients. RVA‐pacing was associated with greater interventricular mechanical dyssynchrony and intra‐LV dyssynchrony than RVOT‐pacing. Septal A’ was adversely affected by intra‐LV dyssynchrony (P < 0.05). Conclusions: Long‐term RVOT‐pacing was associated with superior indices of LV structure and function compared with RVA‐pacing, and was associated with less adverse LA remodeling. If pacing cannot be avoided, the RVOT septum may be the preferred site for right ventricular pacing. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1120‐1126)     

实时三维超声心动图评价右室不同部位起搏对左室收缩同步性的近期影响

目的应用实时三维超声心动图技术评价VVI单腔起搏器置入右室流出道间隔部(RVOT)和右室心尖部(RVA)对左室收缩同步性的近期影响。方法40例房室传导阻滞及心动过缓需置入VVI单腔起搏器的患者,按起搏部位的不同分为RVOT组(n=20)和RVA组(n=20)。观察并比较两组置入起搏器后1周的起搏参数;术前及术后1周左室收缩同步性和心功能等指标。结果术后1周,两组起搏阈值、感知阈值、电极阻抗以及心功能无差异(P>0.05),RVOT组左室同步性指标术前与术后无差异(P>0.05),RVA组左室同步性指标较术前升高,且RVA组较RVOT组明显升高(P均<0.05)。结论VVI单腔起搏右室不同部位,RVOT较RVA更接近生理情况。     

Optimal right ventricular pacing site in chronically implanted patients: A prospective randomized crossover comparison of apical and outflow tract pacing

ObjectivesTo evaluate the long-term functional and hemodynamic effects of right ventricular outflow tract (RVOT) pacing by comparison with right ventricular apical (RVA) pacing.BackgroundAcute studies have suggested that RVOT pacing could significantly improve cardiac performance in comparison with RVA pacing but no data are available in chronically implanted patients.MethodsSixteen patients with chronic atrial tachyarrhythmia and complete AV block were included. Left ventricular ejection fraction (LVEF) was ≥40% in ten and <40% in six. Patients were implanted with a standard DDDR pacemaker connected to two ventricular leads. A screw-in lead was placed at the RVOT and connected to the atrial port. A second lead was positioned at the RVA and connected to the ventricular port. Right ventricular outflow tract and RVA pacing was achieved by programming either the AAIR or the VVIR mode respectively. Four months later patients were randomized so as to undergo either RVOT or RVA pacing for three months according to a blind crossover protocol. Apart from the pacing mode, programming remained unchanged throughout the study. At the end of each period, NYHA class, LVEF, exercise time and maximal oxygen uptake were assessed.ResultsNo significant difference was observed between the two modes for all the parameters analyzed. These identical results were observed in all patients globally, in patients with LVEF ≥40% as in those with LVEF <40%.ConclusionsWithin the limits of this study, no symptomatic improvement or hemodynamic benefit was noted after three months of RVOT pacing, by comparison with RVA pacing.     

Right ventricular outflow versus apical pacing in pacemaker patients with congestive heart failure and atrial fibrillation

INTRODUCTION: Prior studies suggest that right ventricular apical (RVA) pacing has deleterious effects. Whether the right ventricular outflow tract (RVOT) is a more optimal site for permanent pacing in patients with congestive heart failure (CHF) has not been established. METHODS AND RESULTS: We conducted a randomized, cross-over trial to determine whether quality of life (QOL) is better after 3 months of RVOT than RVA pacing in 103 pacemaker recipients with CHF, left ventricular (LV) systolic dysfunction (LV ejection fraction < or = 40%), and chronic atrial fibrillation (AF). An additional aim was to compare dual-site (RVOT + RVA, 31-ms delay) with single-site RVA and RVOT pacing. QRS duration was shorter during RVOT (167 +/- 45 ms) and dual-site (149 +/- 19 ms) than RVA pacing (180 +/- 58 ms, P < 0.0001). At 6 months, the RVOT group had higher (P = 0.01) role-emotional QOL subscale scores than the RVA group. At 9 months, there were no significant differences in QOL scores between RVOT and RVA groups. Comparing RVOT to RVA pacing within the same patient, mental health subscale scores were better (P = 0.03) during RVOT pacing. After 9 months of follow-up, LVEF was higher (P = 0.04) in those assigned to RVA rather than RVOT pacing between months 6 and 9. After 3 months of dual-site RV pacing, physical functioning was worse (P = 0.04) than during RVA pacing, mental health was worse (P = 0.02) than during RVOT pacing, and New York Heart Association (NYHA) functional class was slightly better (P = 0.03) than during RVOT pacing. There were no other significant differences between RVA, RVOT and dual-site RV pacing in QOL scores, NYHA class, distance walked in 6 minutes, LV ejection fraction, or mitral regurgitation. CONCLUSION: In patients with CHF, LV dysfunction, and chronic AF, RVOT and dual-site RV pacing shorten QRS duration but after 3 months do not consistently improve QOL or other clinical outcomes compared with RVA pacing.     

Investigation of pacing site-related changes in global restitution dynamics by non-contact mapping.

AIMS: The determination of dynamic changes in ventricular repolarization may provide insight into arrhythmogenic mechanisms as a consequence of pacing site. This study investigated acute pacing site effects on global characteristics of electrical restitution using high resolution, non-contact mapping (NCM). METHODS AND RESULTS: Activation-recovery intervals (ARIs) were determined from reconstructed left ventricular electrograms by the NCM system and were analysed during pacing from the right atrial appendage (RAA, intrinsic), right ventricular apex (RVA), and right ventricular septum (RVS) with extrasystoles delivered at intermediate and short coupling intervals in anesthetized swine (n = 5). Electrical restitution curves were determined by the S1-S2 pacing protocol. Activation-recovery interval restitution slopes were determined by the overlapping linear segments regression method. Global distribution of repolarization was defined as the coefficient of variation of the ARIs during restitution. The maximum ARI slopes yielded by RVA pacing were significantly greater than RAA pacing (0.44 vs. 0.32; P < 0.05) and RVS pacing (0.44 vs. 0.37; P = 0.05). There was no significant difference between RAA and RVS pacing (0.32 vs. 0.37). The global distribution of ARIs during restitution from RVA pacing was significantly greater than RAA pacing (12.0 vs. 8.1%; P < 0.05). CONCLUSION: Right ventricular apex pacing is associated with impaired global repolarization patterns compared to RAA and RVS. These observations support the hypothesis that RVA pacing may be associated with increased risk of ventricular arrhythmias compared to RVS pacing.