二维超声观察AAI与VVI起搏前后血流动力学的变化

作者对２３例安装永久性起搏器患者，采用二维超声，比较起搏器植入前后血流动力学的变化。结果显示:植入后心房按需起搏（ＡＡＩ）组和心室按需起搏（ＶＶＩ）组的心排血量均明显增加（Ｐ＜０．０５），分别增加４０．６％和２１．２％；但植入后ＶＶＩ组的左室射血分数、每搏量、左室舒张末期容积均降低（Ｐ＜０．０５），ＡＡＩ组无变化。研究表明ＡＡＩ生理性起搏对于患者血流动力学的改善优于ＶＶＩ非生理性起搏。心排血量是评价血流动力学改善的敏感指标     

彩色多普勒超声对不同频率DDD及VVI起搏的血流动力学研究

目的探讨不同频率DDD及VVI起搏的血流动力学变化，并比较DDD及VVI起搏的血流动力学效果。方法186例植入永久心脏起搏器的患者分为两组，DDD组90例，VVI组96例，程控起搏频率从50～90次／min，以彩色多普勒超声评价其血流动力学变化。结果在DDD组70次／min起搏的心排血量（CO）高于50及60次／min起搏（P〈0．05），80—90次／min起搏的CO与70次／min起搏的CO无显著差异。在VVI组起搏频率超过80次／min时CO不再增加。DDD组CO及LVEF在相同起搏频率下显著高于VVI组。结论DDD起搏的血流动力学效果显著优于VVI起搏，最佳频率范围为60—80次／min。     

右心室间隔部起搏和右心室心尖部起搏对血流动力学的影响

目的:比较右心室间隔部(RVS)起搏和右心室心尖部(RVA)起搏对血流动力学的影响。方法:20 例置入DDD起搏器的患者,随机均分为2组,RVS组行RVS起搏,RVA组行RVA起搏;对比观察术前与术后心电图QRS波宽度和形态;比较2组术前和术后6个月随访的左室射血分数(LVEF)、心脏指数(CI)、每搏量 (SV)、二尖瓣血流E峰和A峰最大充盈速度比值(E／A)差异。结果:RVA组起搏心电图Ⅱ导联QRS时限度显著长于RVS组[(0．19±0．02)s:(0．12±0．02)s,P<0．01];术前2组LVEF、CI、SV和E／A均差异无统计学意义。与术前相比,RVA组6个月随访的LVEF、CI、SV和E／A均显著降低[(60．7±5．9)％:(54．8±6．4)％, (2．78±0．31):(2．49±0．26),(81．5±10．0):(68．6±12．5),(1．70±0．48):(1．20±0．39),均P<0．05], RVS组无明显变化[(62．7±6,4)％:(61．14±5．8)％,(2．74±0．33):(2．76±0．25),(82．2±9．2):(78．7±11． 5),(1．62±0．49):(1．61±0．40),均P>0．05]。6个月随访RVS组LVEF、CISV、SV、E／A均显著高于RVA 组(均P<0．05)。结论:RVA起搏扰乱了双心室电同步,导致血流动力学恶化,RVS起搏则尽可能地保证了双心室正常电激动和机械收缩顺序,对血流动力学无不良影响。     

二维超声观察AAI与VVI起搏前后血流动力学的变化

作者对２３例安装永久性起搏器患者，采用二维超声，比较起搏器植入前后血流动力学的变化。结果显示；植入后心房按需起搏（ＡＡＩ）组和心室按需起博（ＶＶＩ０组的心排血量均明显增加（Ｐ〈０．０５），分别增加４０．６％和２１．２％，但植入后ＶＶＩ组在左室射血分散，每搏量，左室舒张末期容积均降低（Ｐ〈０．０５），ＡＡＩ组无变化。研究表明ＡＡＩ生理性起搏对于中层得血流动力学的改善优于ＶＶＩ非生理性起搏，心排血量是     

心脏再同步化治疗起搏参数优化对心脏同步性及心功能的影响

目的 应用组织多普勒研究心脏再同步化治疗(CRT)术后A-V、V-V间期优化对心脏同步性能及心功能的影响,探索A-V、V-V间期优化在增强CRT临床疗效中的作用.方法 32例慢性心力衰竭患者接受CRT治疗,于术后7天、3个月、6个月进行A-V、V-V间期优化,观察心脏同步性和心功能变化.采用彩色超声诊断仪进行图像采集及下线分析.结果 经观察,术后7天、3个月、6个月的A-V间期需行优化的例数分别为28例、10例、6例,V-V间期需行优化的例数分别为29例、6例、5例.与CRT术前相比:CRT治疗术后未优化时的左室12节段组织速度达峰时间标准差明显改善[(68.8±26.4)ms与(41.6±23.1)ms,P＜0.01],左室射血分数增加[(28±4)%与(31±3)%,P＜0.05],主动脉瓣前向血流速度时间积分增加[(13.6±3.1)cm与(15.5±4.3)cm,P＜0.05],舒张早期跨二尖瓣血流峰速和舒张早期心肌组织运动峰速的比值下降(13.1±5.3与9.3±4.3,P＜0.05),左室舒张充盈时间延长[(313.2±93.6)ms与(368.6±97.1)ms,P＜0.05].与术后未优化时相比:术后7天优化心脏同步性指标进一步改善(P＜0.05),心功能指标无明显改变;术后3个月、6个月优化与术后7天优化相比,心脏同步性指标无明显改变,P＞0.05;术后6个月优化的左室射血分数增加,左室舒张充盈时间延长,P＜0.01.结论 CRT术后7天,A-V、V-V间期优化治疗改善心脏同步指标;术后6个月优化进一步改善心功能.     

实时三维超声心动图与心电图指导床旁临时心脏起搏的对比研究

目的比较实时三维超声心动图(RT-3DE)和心电图指导床旁临时心脏起搏的疗效及安全性。方法 49例患者分为A组(RT-3DE组,23例)和B组(心电图组,26例)。穿刺左侧锁骨下静脉,分别在RT-3DE和心电图指导下将普通起搏电极导线植入右心室进行临时起搏,对比观察两组手术起搏成功率、平均操作时间、起搏阈值及电极导线脱位率。结果 A组和B组的起搏成功率分别为100%和92.3%;平均操作时间为(237±94)s和(358±140)s;起搏阈值为(0.85±0.21)V和(0.98±0.33)V,电极导线脱位率为0%和12.5%。两组在平均操作时间方面差异有统计学意义(P0.05)。结论 RT-3DE与心电图指导床旁临时心脏起搏相比,可明显缩短手术操作时间,具有临床实用价值。     

实时三维超声心动图同步显像技术评价心脏再同步起搏治疗参数

目的:应用实时三维超声心动图三平面同步显像技术,评价扩张型心肌病行再同步起搏治疗不同起搏参数时的心肌同步性及心功能的变化。方法:采用实时三平面组织同步显像技术,同步实时获取心尖四腔观、左室心尖两腔观和左室心尖长轴观,局部心肌收缩达峰时间,采用牛眼图模式定量测量左室6个壁12个心肌节段的纵轴收缩达峰时间,测量指标为各节段的达峰时间最大延迟(Ts-max)及达峰时间标准差,同时测量左室射血分数及观察二尖瓣反流程度,观察双心室起搏前后及不同起搏参数时各指标变化。结果:双心室同步起搏后,患者心功能得到明确改善,左室射血分数从(25.3±7.6)%.提高至(39.5±13.9)%(P<0.05);左室舒张充盈时间增加,二尖瓣反流量减少;达峰时间最大延迟由术前的(434.1土215.6)ms缩短至(155.8±43.2)ms(P<0.05),达峰时间标准差由术前的(161.6土30.4)ms缩短至(63.9±21.8)ms(P<0.05);不同起搏参数时,上述各指标的改善程度不同。结论:实时三平面同步显像技术能够客观定量评价不同起搏参数下再同步化起搏治疗慢性心力衰竭的临床效果,双心室同步起搏治疗可改善心力衰竭患者的心功能,不同患者的最优起搏参数不同。     

经胸与经食管超声心动图对心脏人工瓣膜的对比研究

４７例心脏人工机械瓣膜置换术后的病人，经胸超声心动图（ＴＴＥ）和经食管超声心动图（ＴＥＥ）对比研究显示，低估二尖瓣置换后人工瓣膜返流程度的分级和返流的发生率；主动脉瓣和二尖瓣置换的病人，ＴＴＥ探查人工二尖瓣返流的效果硬差。ＴＥＥ能较容易地探查人工二尖瓣瓣周漏。揭示对人工二尖瓣的评价，ＴＥＥ比ＴＴＥ能提供更多更可靠的信息，毫无疑问这是由于ＴＴＥ检查时人工瓣膜材料的声衰减和血流掩盖的影响，但我们的经验揭示，在评价主动脉瓣置换人工瓣膜时，ＴＥＥ并不优于ＴＴＥ。     

Kappa起搏器自动房室搜索功能对血流动力学的影响

目的:研究Kappa系列起搏器自动AV搜索功能对血流动力学的影响。方法:43例接受永久性心脏起搏器治疗的病人中Kappa起搏器组12例.普通DDD起搏器组31例。所有病人均于术前,术后3月行心脏彩超检查,比较两组病人左室射血分数(EF)差异,进行统计学分析。结果:Kappa起搏组EF值较普通DDD起搏组为高(P< 0.05)。结论:Kappa起搏组的自动AV搜索功能较普通DDD起搏组有更积极的血流动力学效果,能改善心脏功能。     

右室流出道间隔部起搏的血流动力学观测

目的比较右室流出道间隔部（RVS）与右室心尖部（RVA）起搏对血流动力学的影响。方法选择具备起搏器植入指征的患者30例,随机分为RVA组与RVS组,采用超声心动图检测左室射血分数（LVEF）、每搏量（SV）、左室短轴缩短率（FS）、心脏指数（CI）,对比观察术前、术后3,6个月差异。并比较术前与术后心电图QRS波宽度。结果两组患者均顺利完成手术。两组QRS波时限均较自身心律时延长,差异有统计学意义（P<0.01）,RVA组起搏QRS时限显著长于RVS组[（158±15）msvs（132±15）ms,P<0.01];RVA组术后3个月随访LVEF,SV,FS,CI较术前均显著降低,均有统计学意义[（59±3）%vs（51±3）%,（79±15）mlvs（71±16）ml,（0.36±0.11）vs（0.31±0.09）,（2.5±0.4）L/（min·m2）vs（2.1±0.4）L/（min.m2）,均P<0.05];RVS组术后3,6个月随访LVEF,SV,FS,CI与术前无显著性差异,RVS组3,6个月随访LVEF,SV,FS,CI均显著高于同期RVA组,均有统计学意义（均P<0.05）。结论RVS起搏尽可能的保证了心室激动和收缩同步性,实现了比RVA起搏较为良好的血流动力学状态。     

Echocardiographic aspects of multisite pacing in patients undergoing cardiac resynchronization therapy

BACKGROUND: Echocardiography has emerged as an accepted approach to define dyssynchrony in patients with advanced stage of heart failure (HF). Unfortunately no single echocardiographic parameter has been established to predict positive response after cardiac resynchronization therapy (CRT) and the nonresponder rate of 20-30% is still a matter of discussion and research. One of the most promising techniques in this regard is two-dimensional strain echocardiography based on speckle tracking with the potential to disclose residual dyssynchrony after primary CRT. An important reason for weak response to CRT is suboptimal position of the coronary sinus (CS) lead. Initial clinical benefit after CRT may mask partial residual dyssynchrony, which may cause worsening and recurrence of HF symptoms over time. Echocardiography helps to define the location of residual dyssynchrony and may identify patients who would benefit from implantation of a second CS-lead and triple-site pacing. If primary CRT fails due to imperfect placement of the CS-lead or due to coronary vein abnormalities and an epicardial approach is not appropriate, dual site pacing of the right ventricle may be an alternative procedure.     

VVI和AAI起搏治疗病窦综合征的远期随访

目的　了解并比较VVI、AAI起搏治疗病窦综合征 (病窦 )的远期效果。方法　分别对87例、62例病窦患者的VVI、AAI起搏治疗进行临床、心电图、2 4小时动态心电图的定期随访 ,随访时间分别为 (60± 3 8)个月和 (3 6± 1 4 )个月。结果　心房颤动的发生率VVI组 (3 4 5 % )明显较AAI组(3 0 % )高 (P <0 0 1) ;血栓栓塞发生率 :VVI组为 10 4 % ,AAI组为 0 ,两组比较差异有显著性 (P <0 0 1) ;心胸比值 :VVI组从术前 0 5 2± 0 0 9增大到术后 0 62± 0 13 (P <0 0 5 ) ,而AAI组无变化 ;VVI组 8例 (9 2 % )发生了心源性死亡 ,而AAI组无 1例发生 ,差异有显著性 (P <0 0 1)。结论　AAI起搏远期随访心房颤动、血栓栓塞、心原性死亡等的发生率明显较VVI起搏低。对病窦患者的预后 ,AAI起搏明显优于VVI起搏。     

双心腔起搏治疗肥厚性梗阻型心肌病的临床应用及血液动力学观察

目的采用双心腔起搏治疗肥厚性梗阻型心肌病１１例，并观察其血液动力学效果。方法１１例患者，男８例，女３例，平均年龄４１岁，均确诊为肥厚性梗阻型心肌病；所有患者均有头晕、活动后气短等临床症状，其中６例患者有晕厥史；超声心动图检查，平均室间隔厚度为２．２ｃｍ，左室流出道压力差平均为４９．０５ｍｍＨｇ（１ｍｍＨｇ＝０．１３３ｋＰａ）。所有患者均置入双心腔起搏器治疗并观察其血液动力学改变。结果在以较短的房室间期（１００ｍｓ）进行双心腔起搏器起搏后，左室流出道压力差从４９．０５ｍｍＨｇ下降至１９．０７ｍｍＨｇ，Ｐ＜０．０５；患者临床症状明显改善，在平均随访９个月中（５～１６个月），无１例患者发生晕厥。结论双心腔起搏治疗肥厚性梗阻型心肌病是一种有效的新的治疗方法，临床应用时应注意选择合适的起搏参数。     

Hemodynamic improvement by right ventricular septal pacing in elderly patients with chronic atrial fibrillation and slow ventricular response

Background and objectives Right ventricular apical (RVA) pacing has been reported impairing left ventricular (LV) performance. Alternative pacing sites in right ventricle (RV) has been explored to obtain better cardiac function. Our study was designed to compare the hemodynamic effects of right ventricular septal (RVS) pacing with RVA pacing. Methods Ten elderly patients with chronic atrial fibrillation (AF) and long RR interval or slow ventricular response (VR) received VVI pacing. The hemodynamic difference between RVS and RVA pacing were examined by transthoracic echocardiography (TTE). Results Pacing leads were implanted successfully at the RVA and then RVS in all patients without complication. The left ventricular (LV) parameters, measured during RVA pacing including left ventricular ejection fraction (LVEF), FS, stroke volume (SV) and peak E wave velocity (EV) were decreased significantly compared to baseline data, while during RVS pacing, they were significantly better than those during RVA pacing. However, after 3-6 weeks there was no statistical significant difference between pre- and post- RVS pacing. Conclusions The LV hemodynamic parameters during RVA pacing were significantly worse than baseline data. The short term LV hemodynamic parameters of RVS pacing were significantly better than those of RVA pacing; RVS pacing could improve the hemodynamic effect through maintaining normal ventricular activation sequence and biventricular contraction synchrony in patients with chronic AF and slow ventricular response.(J Geriatr Cardiol 2005,2(2): 103-106).     

VVI起搏后心房颤动的发生率及影响因素

为探讨ＶＶＩ起搏后心房颤动（Ａｆ）发生率及影响因素，分析我院２９６例ＶＶＩ起搏患者，并与同期２２例生理性起搏（ＡＡＩ５例，ＤＤＤ１７例）患者比较，发现ＶＶＩ起搏后Ａｆ发生率为２５７％（７６／２９６），而生理性起搏后Ａｆ发生率仅４５％（１／２２），有显著性差异Ｐ＜００５）。同时分析比较了ＶＶＩ起搏后Ａｆ发生率与７种影响因素的关系，发现Ａｆ发生率增加除与性别无明显关系外（Ｐ＞００５），在统计学上有显著差异的因素是：年龄较大（≥６０岁，Ｐ＜００５），术前有高血压史（Ｐ＜００１），心功能不全（＞Ⅱ级，Ｐ＜００１），左房内径较大（≥４５ｍｍ，Ｐ＜００１），病态窦房结综合征（无房室传导阻滞，Ｐ＜００５），ＶＶＩ起搏时间较长（≥３年，Ｐ＜００５）。     

Avoidance of right ventricular pacing in cardiac resynchronization therapy improves right ventricular hemodynamics in heart failure patients

Background: Cardiac resynchronization therapy (CRT) applied by pacing the left and right ventricles (BiV) has been shown to provide synchronous left ventricular (LV) contraction in heart failure patients. CRT may also be accomplished through synchronization of a properly timed LV pacing impulse with intrinsically conducted activation wave fronts. Elimination of right ventricular (RV) pacing may provide a more physiological RV contraction pattern and reduce device current drain. We evaluated the effects of LV and BiV pacing over a range of atrioventricular intervals on the performance of both ventricles.
Methods: Acute LV and RV hemodynamic data from 17 patients with heart failure (EF = 30 ± 1%) and a wide QRS (138 ± 25 msec) or mechanical dyssynchrony were acquired during intrinsic rhythm, BiV, and LV pacing.
Results: The highest LV dP/dt_max was achieved during LV pre- (LV paced prior to an RV sense) and BiV pacing, followed by that obtained during LV post-pacing (LV paced after an RV sense) and the lowest LV dP/dt_max was recorded during intrinsic rhythm. Compared with BiV pacing, LV pre-pacing significantly improved RV dP/dt_max (378 ± 136 mmHg/second vs 397 ± 136 mmHg/second, P < 0.05) and preserved RV cycle efficiency (61.6 ± 14.6% vs 68.6 ± 11.4%, P < 0.05) and stroke volume (6.6 ± 4.4 mL vs 9.0 ± 6.3 mL, P < 0.05). Based on LV dP/dt_max, the optimal atrioventricular interval could be estimated by subtracting 30 msec from the intrinsic atrial to sensed RV interval.
Conclusions: Synchronized LV pacing produces acute LV and systemic hemodynamic benefits similar to BiV pacing. LV pacing at an appropriate atrioventricular interval prior to the RV sensed impulse provides superior RV hemodynamics compared with BiV pacing.     

不同起搏方式对起搏器置入患者血浆B型脑钠肽及心脏功能、结构的影响

目的观察不起起搏方式对起搏器置入患者血浆B型脑钠肽及心脏功能、结构的影响。方法选择125例行起搏器置入患者,均置入DDD型起搏器,按心室导线固定部位不同分为右室心尖部起搏组和右室间隔部起搏组,比较两组手术前后心电图QRS间期、血浆B型脑钠肽（BNP）、超声心动图的变化情况。结果术前两组Ⅱ导联QRS间期、BNP、超声心动图检查结果无统计学差异,术后3个月时右室心尖部起搏组左房内径、左室舒张末期内径、室间隔厚度均较右室间隔部起搏组显著增大（P〈0．05）,射血分数显著下降（P〈0．05）,BNP显著升高（P〈0．05）。结论右室心尖部起搏组与右室间隔部起搏相比,心腔扩大,射血分数下降,BNP水平增高明显。     

Comparison of the effects of VVI versus DDD pacing on cardiac baroreflex function

INTRODUCTION: Conventional baroreceptor-heart rate (HR) reflex sensitivity cannot be examined in chronotropically incompetent patients or in pacemaker recipients. However, cardiac baroreceptor reflex sensitivity (BRS)-stroke volume (SV), which is closely and linearly correlated with BRS-HR, may be an alternative in that population. The aim of this study was to compare the BRS-SV in pacemaker recipients with a fixed HR paced in VVI versus DDD modes in the supine and upright positions. METHODS: The pacing mode was set randomly to DDD or VVI with complete atrial and/or ventricular capture, then crossed over to the alternate mode in 9 recipients of dual-chamber pacemakers with atrioventricular (AV) block. Beat-to-beat mean blood pressure and SV were measured in the supine and upright positions, using a tilt table. The BRS-SV, expressed in %/mmHg, was the ratio of low-frequency (LF) power to total power (TP) of SV variability, measured by spectral analysis of spontaneous variations in mean blood pressure and SV. RESULTS: BRS-SV was significantly lower in the VVI than in the DDD mode in the supine (37.2 +/- 26.7 vs 14.5 +/- 7.7%/mmHg) and upright (22.9 +/- 16.9 vs 10.6 +/- 6.6%/mmHg) positions (P < 0.05 for both comparisons). CONCLUSIONS: VVI pacing is adverse from the standpoint of cardiac autonomic baroreflex function. A decreased BRS-SV may be one of the factors involved in the hemodynamic intolerance associated with VVI pacing.