How should we measure left atrium size and function?

Echocardiographic assessment of left atrial size from M-mode or 2D echocardiography measurements has been used in clinical and research studies for years, but its accuracy is now questioned. New techniques, such as 3D and tissue Doppler imaging, assessing velocities, strain and strain rate, provide improved prognostic value in a wide range of diseases. 2D strain imaging using speckle tracking on B-mode images may yield even better, angle-independent, results than tissue Doppler imaging-derived strain echocardiography. Finally, velocity vector imaging is a novel image analysis technique that may be used to quantify left atrial volume.     

Quantitative regional analysis of left atrial function by Doppler tissue imaging-derived parameters discriminates patients with posterior and anterior myocardial infarction.

BACKGROUND: Doppler tissue imaging can now be used for the assessment of left atrial (LA) function. LA function was evaluated by this technique in a group of patients hospitalized for acute myocardial infarction and in a control population. METHODS: Patients were all prospectively imaged with a scanner. To study the LA, a region of interest was located in the proximal part of the lateral and septal LA walls. Doppler tissue imaging, tissue tracking, strain, and delays were recorded. RESULTS: In all, 12 patients with posterior (age 54 +/- 9 years) and 13 with anterior (age 64 +/- 16 years) acute myocardial infarction, along with 16 control patients (age 54 +/- 9 years), were analyzed. Early diastolic septal velocity was found to be the best parameter for discriminating among the 3 groups. Peak strain was also relevant and did not correlate with left ventricular function. CONCLUSIONS: LA is accessible to Doppler tissue imaging analysis. Strain can quantify LA function relatively independently of left ventricular function, and may provide new insights on LA function.     

Atrial Strain Imaging after Repair of Tetralogy of Fallot: A Systematic Review

We performed a systematic review of the literature on assessment of right atrial (RA) and left atrial (LA) deformation by myocardial strain imaging in patients with repaired tetralogy of Fallot. Ten studies with a total of 536 adolescent and adult patients were included, of which 5 evaluated RA deformation, 2 studied LA deformation and 3 assessed deformation of both atria. Seven studies used speckle tracking echocardiography, 2 employed tissue Doppler imaging and 1 applied cardiac magnetic resonance feature tracking. Main findings were (i) reduced regional and/or global RA and LA strain and strain rate consistent with reduced conduit, reservoir and contractile function of the two atria in patients; (ii) associations between RA and LA deformation indices suggestive of atrial–atrial interaction; and (iii) relationships between RA deformation and indices of right ventricular systolic and diastolic function. The lack of data on prognostic value of atrial strain is an important knowledge gap.     

斑点追踪显像与组织多普勒应变评价房间隔缺损封堵术后心房功能对比研究

目的 通过研究封堵器介入治疗房间隔缺损术后患者心房应变,对比斑点追踪显像及组织多普勒应变显像两种方法对心房功能评价的价值.方法 对封堵器介入治疗房间隔缺损成功的40例患者于术后1周内进行超声心动图检查,应用组织多普勒应变显像及斑点追踪显像技术分别测量左心房封堵器处及左心房侧壁应变,对比两种方法评价心房功能的可靠性.结果 两种测量方法的可重复性及后处理分析时间差异无统计学意义.两种方法均显示左心房侧壁应变显著高于封堵器局部应变(组织多普勒:47.31%±27.25% vs 30.06%±14.29%, P<0.01;斑点追踪:43.49%±25.55% vs 12.74%±9.16%, P<0.001).两种方法评价侧壁应变无差异,但斑点追踪封堵器局部应变低于组织多普勒显像,且有5例患者封堵器局部应变为0,而组织多普勒法未见封堵器局部应变为0(χ~2=5.33, P=0.027).结论 斑点追踪显像评价心房形变能力优于组织多普勒应变显像.     

Clinical implications of the echocardiographic assessment of left ventricular long axis function

The assessment of the left and right ventricular long axis function by Doppler echocardiography was started many years ago with the use of M-mode. Two-dimensional echocardiography was subsequently used to study the longitudinal function of the left ventricle. The studies of that era led to useful conclusions. However, tissue Doppler imaging, a relatively new echocardiographic technique, recently became the first choice for such an assessment. Moreover, the advances of tissue tracking and strain rate also have an important contribution. New studies were conducted and new data derived for left and right ventricular function in various cardiac diseases. Τhe aim of this review was to present the accumulated knowledge of the Doppler echocardiography study of the left ventricular long axis function and the relevant clinical implications.     

应变率成像评价左房局部功能的临床研究进展

心肌应变率成像(SRI)是组织速度成像基础上发展起来的一种超声心动图技术,可作为评价心房局部心肌功能的量化指标,目前在各种心脏疾病中的应用得到广泛研究。本文阐述了SRI的定义、测量方法及优缺点,并对其在评价一些心脏疾病左房局部功能的应用进展做一综述。     

The use of transthoracic echocardiography for the assessment of left ventricular systolic and diastolic function in patients with suspected or ascertained chronic heart failure

Several indices are available to assess left ventricular (LV) function. Although ejection fraction (EF) is widely used, it has many limitations. An assessment of LV longitudinal function should be therefore provided as it precedes the impairment of EF. In this context, speckle tracking derived global longitudinal strain is the gold standard but S’ velocity of mitral annulus (by pulsed tissue Doppler) and mitral annular plane systolic excursion (by M-mode) represent more than simple surrogates. LV diastolic assessment should be oriented not to the simple classification of transmitral patterns (E/A ratio and E velocity deceleration time) but to non-invasive estimation of LV filling pressures. This can be mainly obtained from E/e’ ratio, with additional calculation of other measurements such as pulmonary flow atrial reverse velocity, systolic pulmonary arterial pressure and left atrial volume index. This comprehensive assessment could also be useful to differentiate heart failure with reduced and preserved EF in particular.     

房间隔应变率成像鉴别左室舒张功能假性正常表现

目的探讨房间隔应变率成像技术判定左室舒张功能假性正常的应用价值。方法30例正常人与左室舒张功能下降患者52例,脉冲多普勒测量二尖瓣口血流,组织多普勒测量二尖瓣环左室侧壁处速度,应变率成像观察房间隔应变率(SR)曲线、应变(S)曲线变化,SR曲线测量舒张早期峰值SRe,舒张晚期峰值SRa;S曲线测量舒张晚期峰值Sa,测量结果各组进行对照分析。结果左室舒张功能受损各组别SRe、Sa及SRe/SRa明显低于正常组(P<0.01)。结论房间隔应变率成像可鉴别左室舒张假性正常,并可定量评价左室舒张功能下降。     

Ultrasonic imaging of myocardial strain using cardiac elastography

Clinical assessment of myocardial ischemia based on visually-assessed wall motion scoring from echocardiography is semiquantitative, operator dependent, and heavily weighted by operator experience and expertise. Cardiac motion estimation methods such as tissue Doppler imaging, used to assess myocardial muscle velocity, provides quantitative parameters such as the strain-rate and strain derived from Doppler velocity. However, tissue Doppler imaging does not differentiate between active contraction and simple rotation or translation of the heart wall, nor does it differentiate tethering (passively following) tissue from active contraction. In this paper, we present a strain imaging modality called cardiac elastography that provides two-dimensional strain information. A method for obtaining and displaying both directional and magnitude cardiac elastograms and displaying strain over the entire cross-section of the heart is described. Elastograms from a patient with coronary artery disease are compared with those from a healthy volunteer. Though observational, the differences suggest that cardiac elastography may be a useful tool for assessment of myocardial function. The method is two-dimensional, real time and avoids the disadvantage of observer-dependent judgment of myocardial contraction and relaxation estimated from conventional echocardiography.     

组织多普勒及其衍生新技术评价心肌存活性的研究

<正>如何识别心肌存活性是一个具有挑战性的难题。负荷超声心动图评价心肌存活性在临床上已得到较为广泛的应用,但它有一定的局限性:对图像质量要     

应变率成像评价左心室射血分数正常的心力衰竭患者左心房功能

目的 探讨应变率成像(SRI)评价左心室射血功能正常的心力衰竭(HF-NSF)患者左心房功能的价值.方法 对94例心力衰竭患者(LVEF正常组28例、LVEF减低组66例)和36例体检健康者(对照组)行心脏超声检查,获取左心房收缩前容积(Vpre)、左心房最小容积(Vmin)、左心房最大容积(Vmax)、左心房每搏量(LASV)、左心房主动排空分数(LAAEF)、左心房被动排空分数(LAPEF)、左心房射血力(LAEF);在SRI模式下测量心室收缩期应变率(SSr)、心室舒张早期应变率(ESr)、心房收缩期应变率(ASr).结果 Vpre、Vmin、Vmax及LAPEF对照组与LVEF正常组比较差异无统计学意义(P>0.05);LASV、LAAEF及LAEF在两组间比较(18.38±3.07)ml vs(20.68±2.69)ml、(0.39±0.08)%vs(0.46±0.08)%、(44.32±5.92)%vs(46.83±4.20)%,差异有统计学意义(P<0.05);LVEF正常组ASr、SSr高于对照组(2.52±0.44)s-1 vs(2.15±0.42)s-1、(3.05±0.47)s-1 vs(2.74±0.42)s-1(P<0.05);ESr呈递减趋势(2.44±0.56)s-1vs(2.73±0.51)s-1(P<0.05).相关分析显示ASr与LAEF呈显著正相关.结论 SRI可敏感地量化评价HF-NEF患者左心房功能.     

斑点追踪及组织多普勒成像技术评价甲状腺功能减退患者左室舒缩功能

目的 使用斑点追踪及组织多普勒成像技术观察甲状腺功能减退（甲减）患者左室舒缩功能,了解甲减患者在出现临床心血管并发症前是否存在左室舒张和收缩功能异常。方法 对20例甲减患者和30例健康成人进行检查,测量其左室射血分数、左室中间段组织多普勒运动速度及应变率,并脱机运用QLAB软件进行分析。结果 甲减组和正常组的左室收缩功能和左室中间段组织多普勒运动速度比较,差异无统计学意义（P〉0．05）,左室中间段纵向、径向及圆周应变率比较,差异有统计学意义（P〈0．05）。结论 与组织多普勒成像技术比较,斑点跟踪技术能更好地反映甲减患者左室舒缩功能的减低,为临床早期诊断和治疗提供可靠依据。     

Diagnosis by new echocardiographic techniques

Echocardiography has been very powerful for not only evaluating hemodynamics and cardiac function but also finding causes of heart failure. Moreover, recent advancements in echocardiography enable us to assess patients with heart failure more conveniently and precisely. The quality of 2-dimensional echocardiographic images is dramatically improved by introduction of harmonic imaging method and intravenous contrast agents which opacify the left ventricular cavity. Tissue Doppler echocardiography can provide information on regional myocardial velocity thereby enabling assessment of regional as well as global left ventricular function. Strain and strain rate of the regional myocardium can be also determined by the newest technology based on tissue Doppler echocardiography.     

应用超声心动图对2型糖尿病患者左心室舒张功能变化的研究

目的用超声心动图(UCG)检测2型糖尿病(DM)患者心脏的形态结构和心功能状态,评价2型DM患者左心室舒张功能的变化。方法应用脉冲多普勒超声心动图(PDE)及多普勒组织显像技术(DTI)测定了40例2型DM病人、20例健康人二尖瓣口和肺静脉血流频谱及二尖瓣环运动频谱。结果(1)DM组室间隔(IVS)、左心室后壁(LVPW)厚度及左心房内径(LAd)较对照组增大(P<0.05);(2)反映收缩功能的指标两组比较无显著性差异,DM组反映舒张功能的多项指标异常(P<0.05)。结论2型DM患者存在舒张功能异常,DTI测定二尖瓣环运动速度评价左心室舒张功能敏感性高,简便易行。     

超声心动图评价左心房结构及功能的应用进展

左心房功能参数在整体心功能评估中发挥着越来越重要的作用,对多种心血管疾病的走向具有预测价值。左心房功能的早期、准确评估对患者的临床治疗以及预后具有重大意义。超声心动图作为左房功能评估最常用的影像学手段,其每一次突破都显得尤为重要。本文主要对几种常用以及近年来新出现的超声心动图技术在左房结构和功能评估中的进展进行总结。     

定量组织多普勒及应变率成像对高血压患者升主动脉弹性的研究

目的探讨定量组织多普勒和应变率成像在评价升主动脉弹性中的价值,并分析高血压患者升主动脉的弹性特征。方法定量组织多普勒和应变率成像分析高血压组68例患者及无心血管疾病对照组66例健康者的升主动脉前后壁运动,比较两组动脉壁舒张早期、舒张晚期及收缩期的运动速度(Ve、Va、Vs)和应变率(SRe、SRa、SRs),并分别分析运动速度和应变率的相关性。结果高血压组升主动脉前后壁的运动速度和应变率测值均较对照组降低(P<0.05)。结论定量组织多普勒及应变率成像可敏感地反映大动脉弹性的变化。     

A practical approach to the echocardiographic evaluation of diastolic function.

A number of recent community-based epidemiologic studies suggest that 40% to 50% of the cases of heart failure have preserved left ventricular systolic function. Although diastolic heart failure is often not well clinically recognized, it is associated with marked increases in morbidity and all-cause mortality. Doppler echocardiography has emerged as the principal clinical tool for the assessment of left ventricular diastolic function. Doppler mitral inflow velocity-derived variables remain the cornerstone of the evaluation of diastolic function. Pulmonary venous Doppler flow indices and mitral inflow measurements with Valsalva's maneuver are important adjuncts for differentiating normal and pseudonormal mitral inflow patterns. Unfortunately, these Doppler flow variables are significantly influenced by loading conditions and, therefore, the results from these standard techniques can be inconclusive. Recently, color M-mode and Doppler tissue imaging have emerged as new modalities that are less affected by preload and, thus, provide a strong complementary role in the assessment of diastolic function. This review will discuss the diastolic properties of the left ventricle, Doppler echocardiographic evaluation, and grading of diastolic dysfunction.     

组织多普勒衍生新技术评价肥厚型心肌病心房局部功能的研究

目的探讨组织多普勒衍生新技术即组织速度成像及应变率成像评价肥厚型心肌病(HCM)患者心房局部功能的价值。方法 HCM组和健康对照组各30例,测量两组左房前后径,室间隔及左室后壁厚度,左、右室流出道压差,二、三尖瓣口E、A峰(Em、Am及Et、At),计算左房主动排空分数(LAAEF)及左房被动排空分数(LAPEF)。取心尖四腔切面测量左房侧壁(LA)、右房侧壁(RA)、房间隔(IAS)近瓣环部(bas)和中部(mid)的峰值组织速度(Vs、Ve、Va)和峰值应变率(SRs、SRe、SRa)。结果 HCM组左房前后径、室间隔及左室后壁厚度、左室流出道压差及LAAEF明显大于对照组(P<0.05),E/Am、E/At及LAPEF则显著减低(P<0.01)。HCM组LAbas、LAmid及IASbas、IASmid的Ve减低;LAbas、LAmid、IASbas、IASmid和RAmid的SRe减低、SRa增高;LAmid及IASbas、IASmid的SRs减低,与对照组相应各节段测值比较,差异均有统计学意义(P<0.05)。HCM组左房各节段SRa平均值(mSRa)与LAAEF呈显著正相关(r=0.810,P<0.01)。结论 HCM患者的左、右心房局部功能均有不同程度受损,组织速度成像及应变率成像可准确评价心房功能尤其是左心房的局部功能变化情况。     

应变率显像对高血压患者左室舒张功能的评价

目的探讨应变率显像(SRI)技术评价高血压患者左室舒张功能的临床意义.方法获取25例高血压病人和20例正常人二腔观、三腔观和四腔观应变率显像及组织多普勒图像,分析左室各节段心肌舒张期应变率曲线和二尖瓣环运动速度曲线,计算左室各节段应变率(SR)、平均峰值应变率(mSR)、左室平均应变率传播速度(PVS)和二尖瓣环平均运动速度(V).常规测量二尖瓣口E、A、E/A值.结果与正常组相比,高血压组舒张早期V、SR均有明显降低,舒张早期和舒张晚期PVS均降低.舒张早期SR与V呈高度正相关.舒张早期除后间隔基底段和侧壁基底段外其余相应节段心肌SR均有显著降低.结论SRI是一项准确定量评价高血压患者左室整体和局部舒张功能的无创性新技术.     

多普勒组织成像评价房间隔缺损并肺动脉高压患者右心室舒张功能

目的探讨多普勒组织成像(DTI)技术评价房间隔缺损(ASD)并肺动脉高压患者右心室舒张功能的临床意义.方法56例ASD并肺动脉高压患者按肺动脉高压程度分为轻、中、重3组,并选取22例健康人作为正常对照组.采用频谱多普勒技术分别测定三尖瓣口舒张早期血流峰值速度e波、舒张晚期血流峰值速度a波,并计算e/a比值.然后进入DTI条件,测定三尖瓣环舒张早期运动峰值速度E波、舒张晚期运动峰值速度A波,并计算E/A比值.结果ASD并肺动脉高压患者右心室舒张功能随肺动脉压力的升高而逐渐减低;与频谱多普勒检测三尖瓣口充盈参数法相比,DTI法在ASD并轻、中度肺动脉高压患者中,对右心室舒张功能异常检出率更高,而在重度肺动脉高压患者中两者无差别.结论DTI在早期检测ASD并肺动脉高压患者右心室舒张功能减低方面较频谱多普勒具有优越性,其不但能早期预测病情变化,且可以帮助判断病情变化程度.