-
- 毛家亮主任医师 教授
-
医院:
上海交通大学医学院附属仁济医院
科室:
心内科1
- 右室流出道室间隔和右室心尖部起搏心电图的对照研究
- 作者:毛家亮|发布时间:2009-02-08|浏览量:2365次
郝静毛家亮* 张琪 章隆泉 刘辉 康瑜 周笙珩何奔 张彦周 黄定九 陈润芬
摘要 目的:通过比较右室流出道(RVOT)室间隔和右室心尖部起搏患者的体表心电图(ECG),从心脏电生理活动的角度,探讨RVOT室间隔起搏在影响心功能方面优于右室心尖部起搏的可能因素。 方法:永久起搏器植入术后患者70例(RVOT室间隔起搏40例,右室心尖部起搏30例),对照比较RVOT室间隔和右室心尖部起搏患者的ECG,并和正常人的ECG作比较。 结果:RVOT室间隔起搏QRS波电轴(QRSa)88±50。,属于正常QRSa,QRS波宽度(QRSd)比右室心尖部起搏窄0.018s(0.113±0.022 vs 0.131±0.032s,p=0.0011),但两组的矫正Q-T间期(QTc)无统计学差异(0.43±0.028 vs 0.44±0.045s,p=0.5496),均较正常组延长。 结论:RVOT室间隔起搏ECG与右室心尖部起搏比较,QRSa不偏,近似窦性心律,能获得接近正常生理性激动顺序和时间模式, 且QRS波时限明显缩短,有利于心室正常顺序激动和双心室同步性,可能对预防和改善心功能有积极的影响。上海仁济医院心内科毛家亮
关键词 右室流出道(RVOT);室间隔;右室心尖部;心电图(ECG)
A tentative study & comparision between right ventricular outflow tract septal pacing and apex one
Haojing Maojialiang Zhangqi Zhanglongquan Liuhui Kangyu Zhoushengheng Hebeng Zhangyanzhou Huangdingjiu Chenrunfen
Abstract Objective: Explore the contribution ventricular septal pacing makes in improving heart fuctionality, from the perspective of cardio-electrical-physiological activitity, by comparing the body surface electrocardiogram (ECG) of right ventricular outflow tract (RVOT) ventricular septal pacing patient and right ventricular apical pacing one. Method: Take the 70 patients implanted with permanent pacemaker after operation for example, ( with 40 cases of RVOT ventricular septal pacing, 30 of right ventricular apical pacing), contrast the ECG of patients of RVOT ventricular septal and right ventricular apical and then put them in comparison with ECG of normal people. Result: RVOT ventricular septal pacing patients QRSa 88+-50, normal and QRSd 0.018s narrower than right ventricular apical pacing. There is no statistical difference between two groups of QTc, longer than normal group. Conclusion: Vector heart rhythem nodal When ECG Vector of RVOT ventricular septal pacing behavors close to nodal heart rhythem, it can gain normal physiological sextual excitement and time modual, effectively shorten QRSa time limit, and maximally retain normal heart excitement order and dual-heart sychronization. Therefore, it is more beneficial to preventing and improving heart functionality compared with right ventricular apical pacing.
Keywords right ventricular outflow tract (RVOT); septal; right ventricular apex; electrocardiogram (ECG)
引言 长期右室心尖部起搏会对心功能造成不利的影响,这可能是传统右室心尖部起搏时,激动顺序从心尖部传至心底部、而且激动从右心室传至左心室,人为的造成电生理活动异常所致,在ECG上表现为QRS波电轴(QRSa)偏移,QRS波宽大畸形。近年来研究表明,右室流出道(RVOT)室间隔起搏较右室心尖部起搏对心功能有利,所以理论上讲,RVOT室间隔起搏ECG表现应优于右室心尖部,即QRSa偏移少,QRS波较窄。但目前仅有的研究并没有较好的涉及RVOT室间隔起搏QRSa偏移问题,也没有明确表明RVOT室间隔起搏时,它的QRS波宽度(QRSd)与右室心尖部起搏相比有明显缩短1-9。为此,本文选择RVOT室间隔部和右室心尖部两组起搏病人,对照、比较及分析这两组QRSa和QRSd的变化及差异。
1.资料和方法
1.1 患者资料
入选2006年5月至2006年10月,上海市仁济医院行永久起搏器植入术患者70例,男性32例,女性38例,平均年龄73.81±11.06岁。起搏器植入适应症为各类缓慢性心律失常,70例患者中病窦综合症42例,二度或三度房室传导阻滞28例,符合起搏器置入的I类或IIa类适应证。其中40例为RVOT室间隔起搏(室间隔组),30例为右室心尖部起搏(心尖部组)。另随机选取30例正常人的心电图作为参照组。
1.2 起搏系统
RVOT室间隔起搏患者中,双腔起搏(DDD)24例,单腔起搏(VVI)16例,使用的起搏器为Medtronic SD303型12例,SS303型12例,KD701型2例;S.T.JUDE DC5256型10例, SC+2402L型4例。右室起搏导线均选用主动固定电极即螺旋电极,右房导线选用常规被动固定电极。右室心尖部起搏患者中DDD8例,VVI22例,使用的起搏器为Medtronic SS303型20例,SDR303型1例,KDR701型3例,S.T.JUDE DC5256型3例,SC+2402L型2例,DR5356型1例。右室心尖部起搏导线均使用被动固定电极。
1.3 电极部位的确定
RVOT室间隔起搏点位于肺动脉圆锥下方,心脏X线后前位(AP)示平行于冠状静脉窦或心大静脉,左前斜位(LAO)40。明确电极头端指向脊柱为室间隔方向。右室心尖部起搏点在X线后前位(AP)即能明确。
1.4 起搏ECG的研究方法
记录病人术后的ECG,观察12标准导联起搏时的QRS波群方向及宽度,计算QRSa,取II、V1导联QRSd的平均值为每例的QRSd。同时,观察起搏时的R波、S波振幅,全面比较两种起搏方式患者的ECG,并以正常人的ECG作为参照,观察两组与正常ECG的异常程度,分析它们之间的统计学差异。
1.5 统计学处理
定量资料采用均数±标准差表示,应用SAS统计软件包及MicroSoft Excel软件进行统计分析,其中两组间比较采用团体t检验或校正t检验(两组方差不齐时),以P<0.05为有统计学差异。
2.结果
术后ECG统计分析显示,40例RVOT室间隔起搏病例中,26例(65%)QRSa不偏,9例QRSa右偏,5例QRSa左偏,平均QRSa为87.97±50.27。。30例右室心尖部起搏病例中,仅有14例(46%)QRSa不偏,16例QRSa左偏,平均QRSa为-33.09±52.84。,与室间隔组有统计学差异(P=0.0001)。两组的平均QRSa和正常组相比都有统计学差异(P均<0.01),即两组的电轴都有偏向,室间隔组稍右偏,心尖部组左偏。室间隔组中21例(53%)6个肢导联QRS波形态与自身QRS波形态一致或相似,在心尖部组中仅有7例(23%)。室间隔组平均QRSd为0.1131±0.0219s,心尖部组为0.1314±0.0324s,比室间隔组宽0.0183s(P=0.0011),且一部分病例(9例)中有室内传导阻滞表现,呈左束支传导阻滞图形。两组的平均QRSd较正常组分别延长0.0244s、0.0427s(0.1131±0.0219 vs 0.0887±0.0104s;0.1314±0.0324 vs 0.0887±0.0104s,P均<0.01)。室间隔组和心尖部组的QT/QTc均无统计学差异,较正常组分别延长0.0141s、0.0206s(0.4344±0.0280 vs 0.4203±0.0167s;0.4409±0.0450 vs 0.4203±0.0167s,P均<0.05)。室间隔组中32例(80%)V1至V6导联R波振幅逐渐升高,S波深度逐渐变浅,且V1T波直立,V3导联不倒置(正常ECG表现),心尖部组中为17例(57%)。心尖部组的V1导联S波、V5导联R波振幅与正常组无统计学差异,室间隔组则比正常组明显增高0.6V、0.3V(P均<0.05),但仍在正常范围(SV1波不超过2V,RV5波不超过2.5V)。(见表一)。
表一 室间隔组、心尖部组及正常组的ECG比较
组别 |
例数 |
QRSa |
QRSd(s) |
QT(s) |
室间隔组 |
40 |
87.97±50.27#,* |
0.1131±0.0219#,* |
0.4166±0.0380#,* |
心尖部组 正常组 |
30 30 |
-33.09±52.84#,Φ52.53±22.81*,Φ |
0.1314±0.0324#,Φ 0.0887±0.0104*,Φ |
0.4277±0.0524#,Φ 0.3757±0.0257*,Φ |
P值 |
|
0.0001# |
0.0011# |
0.3676# |
0.0008* |
0.0016* |
0.0001* | ||
0.0001Φ |
0.0001Φ |
0.0002Φ |
(续表一)
组别 |
例数 |
QTc(s) |
V1导联S波(mV) |
V5导联R波(mV) |
室间隔组 |
40 |
0.4344±0.0280#,* |
1.2469±0.6998#,* |
1.5563±0.7687#,* |
心尖部组 正常组 |
30 30 |
0.4409±0.0450#,Φ 0.4203±0.0167*,Φ |
0.7364±0.5403#,Φ 0.6533±0.2622*,Φ |
1.0000±0.7400#,Φ 1.2100±0.3745*,Φ |
P值 |
|
0.5496# |
0.0058# |
0.0106# |
0.0195* |
0.0001* |
0.0276* | ||
0.0255Φ |
0.3226Φ |
0.1860Φ |
注:#、*、Φ分别是指室间隔组和心尖部组、室间隔组和正常组以及心尖部组和正常组比较的P值。
3.讨论
正常的心室激动顺序和同步性是保持心室收缩和舒张功能的先决条件,也是起搏心律影响心功能的两个重要因素。传统右室心尖部起搏的缺点是改变了正常的心室激动顺序,起搏时脉冲由心尖部向心底部逆行传导,左室大部分是由心肌传导,除极速度较慢,形成左室心肌本身和左右心室除极不同步,室间隔、心尖部与左心室后壁呈反常运动,从而影响心脏的泵血功能,ECG上显示为宽QRS波和左束支传导阻滞的图形10,11。在MOST、DAVID试验12、13中,传统右室心尖部起搏会诱发和加重充血性心力衰竭。Karpawich等14证明在急性期试验中,正常的左室(LV)功能仅来源于持续的间隔部起搏;相反右室(RV)心尖部起搏引起LV收缩和舒张功能恶化。心室激动的正常顺序是从心底部传导至心尖部,并保持左右心室除极同步,ECG上表现为窄QRS波和QRSa在正常的范围之内。心室起博时QRS形态与自身QRS形态的一致或相似性,通常可反映起博时的心室激动顺序更符合自身心室激动顺序,起博时的QRS时限则可反映双侧心室收缩时的同步性。本研究结果显示,心尖部组QRSa明显偏移,且以左偏为主,部分还呈左束支传导阻滞的图形,表明右室心尖部起搏改变了正常的心室激动顺序,起搏时脉冲激动不仅由心尖部向心底部逆行传导,而且激动还自右室向左室传导,形成左右心室除极不同步;且心尖部组QRSd为0.1314±0.0324,>0.12s, 有明显的室内传导阻滞表现,提示右室心尖部起搏对心室激动顺序以及同步性的改变,使心脏收缩丧失了整体协调性,心室顺应性降低,会对血流动力学和心功能产生多方面的不良影响。
迄今为止,未见详细研究报道RVOT室间隔对QRSa的影响。而在本研究中,室间隔组QRSa基本不偏,80%各主要导联的QRS波群方向与正常ECG一致,65%QRSa正常,在QRSa有偏向的患者中,除QRSa偏向外,主要导联方向、振幅未见明显异常。表明RVOT室间隔起搏激动从室间隔向左右两边传导,较好的保持左右心室同步;QRSd反应室内传导阻滞,但现有的研究也并没有明确证明,RVOT室间隔起搏的QRSd与心尖部起搏相比有显著差别1-9,只有一些论著提示RVOT室间隔起搏的QRSd可见微小的缩短15-17。虽然上述两组QRSd与正常人参照组比较都有明显增宽,但室间隔组QRSd较心尖部组明显变窄,平均QRSd为0.113±0.022s,比正常组延长0.024s(P=0.0016),但仍<0.12s,尤其是比心尖部组缩短了0.018s(P=0.0011),提示RVOT室间隔起搏激动了较心尖部起搏接近正常的传导系统,引起较正常的心室激动顺序,传导方向以及引发的心肌收缩同步性与正常心室激动时相近,且心室内除极的同步性也较强,减少室内传导阻滞,有效缩短左右室激动时间,从而获得较好的血流动力学,通过减少或避免左室负性重构改善左室功能,起到预防和改善心功能的作用。
4.结论
保持心室正常的电激动顺序和同步性是改善血流动力学从而改善心功能的基础。ECG显示,RVOT室间隔起搏QRSa接近窦性心律,QRSd较右室心尖部起搏明显缩短,提示RVOT室间隔起搏有助于保持较为正常生理性激动顺序和时间模式,最大程度恢复左右室电-机械活动的协调和同步,有利于预防和改善心功能。
参考文献
1. Buckingham TA, Candinas R, Attenhofer C, et al. Systolic and diastolic function with alternate and combined site pacing in the right ventricle. Pacing Clin Electrophysiol 1998; 21:1077?1084.
2. Alboni P, Scarfo S, Fuca G, et al. Short-term hemodynamic effects of DDD pacing from ventricular apex, right ventricular outflow tract and proximal septum. Giornale Italiano di Cardiologia 1998; 28:237?241.
3. Victor F, Leclercq C, Mabo P, et al. Optimal right ventricular pacing site in chronically implanted patients: a prospective randomized crossover comparison of apical and outflow tract pacing. J Am Coll Cardiol 1999; 33:311?316.
4. Schwaab B, Frohlig G, Alexander CS, et al. Influence of right ventricular stimulation site on left ventricular function in atrial synchronous ventricular pacing. J Am Coll Cardiol 1999; 33:317?323.
5. Buckingham TA, Candinas R, Duru F, et al. Acute hemodynamic effects of alternate and combined site pacing in patients after cardiac surgery. Pacing Clin Electrophysiol 1999; 22(6 Pt 1):887?893.
6. Gold MR, Brockman R, Peters RW, et al. Acute hemodynamic effects of right ventricular pacing site and pacing mode in patients with congestive heart failure secondary to either ischemic or idiopathic dilated cardiomyopathy. Am J Cardiol 2000; 85:1106?1109.
7. Kolettis TM, Kyriakides ZS, Tsiapras D, et al. Improved left ventricular relaxation during short-term right ventricular outflow tract compared to apical pacing. Chest 2000; 117:60?64.
8. Bourke JP, Hawkins T, Keavey P, et al. Evolution of ventricular function during permanent pacing from either right ventricular apex or outflow tract following AV-junction ablation for atrial fibrillation. Europace 2002; 4:219?228.
9. Buckingham TA, Candinas R, Schlapfer J, et al. Acute hemodynamic effects of atrioventricular pacing at differing sites in the right ventricle individually and simultaneously. Pacing Clin Electrophysiol 1997; 20(4 Pt 1):909?915.
10. Baldasseroni S, Opasich C, Gorini M, et al. Left bundle-branch block is associated with increased 1-year sudden and total morality rate in 5517 outpatients with congestive heart failure:A report from the Italian Network on Congestive Heart Failure. Am Heart J 2002;143:398-405
11. Prinzen FW, Peschar M. Relationship between the pacing induced sequence of activation and left ventricular pump function in animals. Pacing Clin Electrophysiol 2002;25:484-498.
12. Sweeney MO, Hellkamp AS, Greenspon AJ, et al. Baseline QRS duration >>120
milliseconds and cumulative percent time ventricular paced predicts increased risk of heart failure, stroke, and death in DDDR-paced patients with sick sinus syndrome in MOST (Conference Abstract). PACE. April 2002;25(4, Part II):690.
13. Wilkoff BL, Cook JR, Epstein AE, et al. Dual chamber pacing or ventricular back-up pacing in patients with an implantable defibrillator. The Dual Chamber and VVI Implantable Defibrillator (DAVID) Trial. JAMA 2002;288:3115-3123.
14. Karpawich PP, Mital S?Comparative left ventricular function following atrial, septal, and apical single chamber heart pacing in the young?PACE, 1997, 20:1983-1988
15. Stambler BS, Ellenbogen K, Zhang X, et al. Right ventricular outflow versus apical pacing in pacemaker patients with congestive heart failure and atrial fibrillation. J Cardiovasc Electrophysiol 2003; 14:1180?1186.
16. Mera F, Delurgio D, Patterson RE, et al. A comparison of ventricular function during high right ventricular septal and apical pacing after His-bundle ablation for refractory atrial fibrillation. Pacing Clin Electrophysiol 1999; 22:1234?1239.
17. Tse HF, Wong KK, Tsang V, et al. Functional abnormalities in patients with permanent right ventricular pacing: the effects of sites of electrical stimulation. J Am Coll Cardiol 2002; 40:1451?1458.
TA的其他文章: